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Gear Talk => EOS Bodies - For Stills => Topic started by: faustino on February 24, 2014, 12:31:30 PM

Title: Crop sensors better than full frame for macro photography?
Post by: faustino on February 24, 2014, 12:31:30 PM
Many people claim that cropped sensors are actually better than full frame and larger sensors for macro applications.
Here is an example:
http://www.43rumors.com/micro-four-thirds-and-macro-photography-by-eugene-kitsios/ (http://www.43rumors.com/micro-four-thirds-and-macro-photography-by-eugene-kitsios/)

Their argument is that for macro photography DoF is the limiting factor. They say that to get the same DoF, the larger the sensor, the smaller the aperture needs to be, which would offsett the light gathering capacity of larger sensors.

As an example, if we compare full frame vs. 4/3 sensors:
- full frame is roughly four times larger than 4/3 (measuring the surface), thus has virtually a two stop advantage in terms of light gathering capacity;
- anyhow, if with four thirds sensor we need to close the aperture to f/8, then on a full frame sensor we would need to close the aperture at f16 to get the same DoF, thus loosing two stop of light (offsetting completely the larger sensor advantage).
I am not sure if the second point is correct. The comparison shall be done considering different lenses on the two systems:
- if we use a 50mm macro on the 4/3 sensor, for correct comparison (to get the same angle of view), a 100mm lens should be used on the full frame (I know there would be slight differences in the final image due to the different aspect ratio).

I am skeptical about the above argument, anyhow I am unable to tell why it would be wrong.
What do you think, is really a crop sensor better than full frame for macro photography? Or is the full frame better? In the latter case, can you explain why?

Thanks!
Fausto
Title: Re: Crop sensors better than full frame for macro photography?
Post by: neuroanatomist on February 24, 2014, 12:39:37 PM
The argument is wrong.  The reason you have deeper DoF with a smaller sensor is that to frame the subject identically, you're further away from the subject or using a shorter focal length.  If you're using the same focal length, you're trading optical magnification for that extra DoF (at macro distances and at the same magnification, the crop sensor actually has very slightly shallower DoF than FF, but the area framed is smaller).  Also, the extent that you need to stop down the FF camera to match the DoF, you can boost the ISO to compensate and have the same image noise, so nothing lost.

I discussed the trade-offs a short time ago in another thread:

Fundamentally, in most use cases, the only meaningful benefit of an APS-C camera is the lower cost….

Macro is potentially another one of those 'exception' use cases.  I say potentially, becuase it really depends on what you mean by macro.  Formally, 'macro' generally means 1:1 magnification (or higher), and anything less than that (0.1x - 1x mag) is considered 'close-up' photography.  If you're at 1:1 with a macro lens, you're at the MFD (or closer if you go higher with tubes) - that means there's no DoF 'advantage' (i.e. more of it) with APS-C.  The APS-C sensor (e.g. 18-20 MP) is going to give you more pixels on target at a given magnification compared to a FF sensor (e.g. 20-22 MP), whereas the FF sensor will give you a wider AoV at that magnification. 

Below is an example of that (shot with the MP-E 65mm on a 1D X and EOS M, both at the same distance from the coin for equivalent optical magnification, and since both use 18 MP sensors, no down- or up-scaling is required for the comparison).  At 1x mag with FF you can frame nearly the whole quarter while APS-C crops much of the coin away but gives you higher resolution at the pixel level.

(http://www.canonrumors.com/forum/index.php?action=dlattach;topic=19666.0;attach=45074;image)

Personally, I usually choose FF for macro (and have done so since having both the 7D and 5DII).
Title: Re: Crop sensors better than full frame for macro photography?
Post by: alexturton on February 24, 2014, 01:53:01 PM
Take the argument to the extreme and consider something like and iphone 5s. It has a tiny sensor so everything is always in focus. But it still has an f2 lens in terms of light transition. So sometimes I can get a better macro shot in low light on my 5s than I could on my 5d mk iii. Because to get an equivalent depth of field I'd have to stop down to f18 which would push up the ISO to extreme.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: faustino on February 24, 2014, 02:49:04 PM
Thank you for your super quick replies.
I have only one additional question, probably redundant, to be sure my understanding is correct:

Shooting the same subject at the same distance with the following setups, Will I get the same image in terms of quality, perspective, and DoF (more or less)?
- Crop sensor setup: EOS 7d + EF-S 60mm f2.8 Macro USM @f/8 aperture
- Full frame sensor setup: EOS 1dx + EF 100mm f/2.8L Macro IS USM @f/11 aperture

If yes, then there would be no technical advantage of one setup over the other, except weight in favor of the crop setup, and flexibility in favor of the full frame setup (e.g. 1dx + 100mm used @f2.8 for portrait, combination that would not give the same result with the crop setup).


Title: Re: Crop sensors better than full frame for macro photography?
Post by: Albi86 on February 24, 2014, 02:52:44 PM
Many people claim that cropped sensors are actually better than full frame and larger sensors for macro applications.
Here is an example:
http://www.43rumors.com/micro-four-thirds-and-macro-photography-by-eugene-kitsios/ (http://www.43rumors.com/micro-four-thirds-and-macro-photography-by-eugene-kitsios/)

Their argument is that for macro photography DoF is the limiting factor. They say that to get the same DoF, the larger the sensor, the smaller the aperture needs to be, which would offsett the light gathering capacity of larger sensors.

As an example, if we compare full frame vs. 4/3 sensors:
- full frame is roughly four times larger than 4/3 (measuring the surface), thus has virtually a two stop advantage in terms of light gathering capacity;
- anyhow, if with four thirds sensor we need to close the aperture to f/8, then on a full frame sensor we would need to close the aperture at f16 to get the same DoF, thus loosing two stop of light (offsetting completely the larger sensor advantage).
I am not sure if the second point is correct. The comparison shall be done considering different lenses on the two systems:
- if we use a 50mm macro on the 4/3 sensor, for correct comparison (to get the same angle of view), a 100mm lens should be used on the full frame (I know there would be slight differences in the final image due to the different aspect ratio).

I am skeptical about the above argument, anyhow I am unable to tell why it would be wrong.
What do you think, is really a crop sensor better than full frame for macro photography? Or is the full frame better? In the latter case, can you explain why?

Thanks!
Fausto

For tripod-based macro work, where you can work at ISO 100 and maybe set the lighting how you like, the advantages of a bigger sensor don't really show all that much. The higher pixel density can actually be the decisive advantage, since macro lenses are typically very sharp.

Title: Re: Crop sensors better than full frame for macro photography?
Post by: faustino on February 24, 2014, 02:57:28 PM
Take the argument to the extreme and consider something like and iphone 5s. It has a tiny sensor so everything is always in focus. But it still has an f2 lens in terms of light transition. So sometimes I can get a better macro shot in low light on my 5s than I could on my 5d mk iii. Because to get an equivalent depth of field I'd have to stop down to f18 which would push up the ISO to extreme.

Well... I have seen people taking better pictures with their iPhone than I with my 5dmk3 + a bunch of L series lenses. Though, I have to candidly admit, the problem was not in the reflex; rather, it was located few centimeters behind the viewfinder.
 :-[
Title: Re: Crop sensors better than full frame for macro photography?
Post by: 9VIII on February 24, 2014, 03:07:47 PM
Once again how much of an advantage you get depends on how much cropping you're doing. If you're shooting a bug that only takes up a fraction of the frame then crop sensors will have the advantage, and if you're like me and you prefer looking at things at 100% all the time anyway, then crop should also be the way to go.

The only time I would care about using a lower aperture vs. a smaller sensor is if moving to such a small aperture that it starts to affect image quality.
In my last bunch of macro shots I could see the difference in detail between f16 and f22, but my framing wasn't such that the loss of fine detail actually ruined the image.
The bigger problem was actually long exposure sensor noise, which can be corrected in post, but it's still at a cost to IQ.
After that I ordered a proper soft box and multi-bulb CFL adapters to stick in lamps (should produce around 8000 lumens), getting my shutter speed down should help more than anything.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: neuroanatomist on February 24, 2014, 03:09:49 PM
Take the argument to the extreme and consider something like and iphone 5s. It has a tiny sensor so everything is always in focus. But it still has an f2 lens in terms of light transition. So sometimes I can get a better macro shot in low light on my 5s than I could on my 5d mk iii. Because to get an equivalent depth of field I'd have to stop down to f18 which would push up the ISO to extreme.

Fine.  Now, because image noise is determined by the total light gathered, which is proportional to the area of the sensor, you have to figure in the effect of sensor size on ISO noise.  What that means is a shot on the iPhone 5s at base ISO (ISO 32) has the same level of noise as a shot on your 5DIII at ISO 1600.  Want to see what the noise at max ISO on the iPhone 5s (ISO 3200) would look like on the 5DIII?  Set ISO 102400 (H2) and push the exposure 2/3-stop in post.  Ok, the iPhone doesn't look that bad, but that's only because of massive NR that obliterates the detail in the iPhone shot.

So, no - there's no DoF advantage to a smaller sensor.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: faustino on February 24, 2014, 03:48:09 PM
What about the previous comparison I was suggesting?

Which setup would give a better image?
- Crop sensor setup: EOS 7d + EF-S 60mm f2.8 Macro USM @f/8 aperture shooting from 10cm
- Full frame sensor setup: EOS 1dx + EF 100mm f/2.8L Macro IS USM @f/11 aperture shooting from 10 cm

Or would it be a tie? My understanding is that it would more or less be a tie.

Thanks,
Fausto
Title: Re: Crop sensors better than full frame for macro photography?
Post by: neuroanatomist on February 24, 2014, 03:54:21 PM
You'd get a sharper image from the FF sensor.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: mackguyver on February 24, 2014, 04:16:59 PM
You'd get a sharper image from the FF sensor.
Yep - check this out:
http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=335&Camera=736&Sample=0&FLI=0&API=4&LensComp=674&CameraComp=453&SampleComp=0&FLIComp=0&APIComp=5 (http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=335&Camera=736&Sample=0&FLI=0&API=4&LensComp=674&CameraComp=453&SampleComp=0&FLIComp=0&APIComp=5)

Or how about 100L @f/8 on crop vs. 180L @f/11 on FF:
http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=674&Camera=736&Sample=0&FLI=0&API=4&LensComp=109&CameraComp=453&SampleComp=0&FLIComp=0&APIComp=4 (http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=674&Camera=736&Sample=0&FLI=0&API=4&LensComp=109&CameraComp=453&SampleComp=0&FLIComp=0&APIComp=4)
Title: Re: Crop sensors better than full frame for macro photography?
Post by: faustino on February 24, 2014, 04:46:05 PM
You'd get a sharper image from the FF sensor.
Yep - check this out:
http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=335&Camera=736&Sample=0&FLI=0&API=4&LensComp=674&CameraComp=453&SampleComp=0&FLIComp=0&APIComp=5 (http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=335&Camera=736&Sample=0&FLI=0&API=4&LensComp=674&CameraComp=453&SampleComp=0&FLIComp=0&APIComp=5)

Or how about 100L @f/8 on crop vs. 180L @f/11 on FF:
http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=674&Camera=736&Sample=0&FLI=0&API=4&LensComp=109&CameraComp=453&SampleComp=0&FLIComp=0&APIComp=4 (http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=674&Camera=736&Sample=0&FLI=0&API=4&LensComp=109&CameraComp=453&SampleComp=0&FLIComp=0&APIComp=4)




Very informative! Thanks!

Title: Re: Crop sensors better than full frame for macro photography?
Post by: digital paradise on February 24, 2014, 05:29:13 PM
I had far better success with my FF over my crop bodies for IQ. I'm talking extreme macros. MP-E lens   
Title: Re: Crop sensors better than full frame for macro photography?
Post by: CarlTN on February 24, 2014, 06:21:09 PM
Many people claim that cropped sensors are actually better than full frame and larger sensors for macro applications.
Here is an example:
http://www.43rumors.com/micro-four-thirds-and-macro-photography-by-eugene-kitsios/ (http://www.43rumors.com/micro-four-thirds-and-macro-photography-by-eugene-kitsios/)

Their argument is that for macro photography DoF is the limiting factor. They say that to get the same DoF, the larger the sensor, the smaller the aperture needs to be, which would offsett the light gathering capacity of larger sensors.

As an example, if we compare full frame vs. 4/3 sensors:
- full frame is roughly four times larger than 4/3 (measuring the surface), thus has virtually a two stop advantage in terms of light gathering capacity;
- anyhow, if with four thirds sensor we need to close the aperture to f/8, then on a full frame sensor we would need to close the aperture at f16 to get the same DoF, thus loosing two stop of light (offsetting completely the larger sensor advantage).
I am not sure if the second point is correct. The comparison shall be done considering different lenses on the two systems:
- if we use a 50mm macro on the 4/3 sensor, for correct comparison (to get the same angle of view), a 100mm lens should be used on the full frame (I know there would be slight differences in the final image due to the different aspect ratio).

I am skeptical about the above argument, anyhow I am unable to tell why it would be wrong.
What do you think, is really a crop sensor better than full frame for macro photography? Or is the full frame better? In the latter case, can you explain why?

Thanks!
Fausto

I agree, for macro photography, a crop sensor has the edge.  Unless of course, you're a fan of focus stacking 10 or more images...which I'm not.  A full frame sensor necessarily requires more focus stacking, unless you want your macro images with shallow depth of field...in which case either FF or crop are ok for that.  I don't profess to be a macro expert, though...but I do know that a macro image I shot with an effective 270mm focal length at f/20 on a crop camera, would have needed to be at f/45 or smaller on a full frame sensor, and would have provided 1.6x less magnification to boot.

Let's just be honest and say that generally, full frame sensors have an advantage for medium or wide angle, non macro photography (the advantages there are vast and rarely disputed).  Full frames can also be useful for longer distance telephoto photography (and can be vital for it in low light).  But under optimum conditions, good light, and with the "perfect" lens, a crop sensor can and usually does have a reach advantage.  And for macro with good or controlled light (and especially with stationary subjects and tripods or other mounting devices), I honestly see a disadvantage with a full frame sensor, over a crop sensor (unless perhaps the very poor performing 12 MP crop sensor that was recently discontinued).
Title: Re: Crop sensors better than full frame for macro photography?
Post by: LetTheRightLensIn on February 24, 2014, 07:36:34 PM
It's sort of a wash. The APS-C cameras often have higher density but you can get that back with an extension tube and if you take things really far DOF and so on become tricky so it's not quite like birding where you can always easily go for more and more reach.

I don't have time to get into it but the short of it is that is basically comes out to be a wash and you can use APS-C or FF DSLR equally well for macro stuff except in the very rare occasion so long as you have a few cheap extension tubes (and sometimes those won't even be needed) and if you have the MPE then it's really pretty meaningles between the two other than in very particular and tricky scenarios when you are really maxing out an dhave the ability and scenario that lets you max out without messing up.

The size vs mag vs diffraction vs noise and so on all just kinda balances out for macro, again don't have time to get into it, maybe someone has.

For stuff like distant birds though the aps-c cams with high density are hard to beat with FF though.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: neuroanatomist on February 24, 2014, 08:45:00 PM
I agree, for macro photography, a crop sensor has the edge.  Unless of course, you're a fan of focus stacking 10 or more images...which I'm not.  A full frame sensor necessarily requires more focus stacking, unless you want your macro images with shallow depth of field...in which case either FF or crop are ok for that.  I don't profess to be a macro expert, though...but I do know that a macro image I shot with an effective 270mm focal length at f/20 on a crop camera, would have needed to be at f/45 or smaller on a full frame sensor, and would have provided 1.6x less magnification to boot.

Sorry, but no - you can't have your cake and eat it, too.  The deeper DoF with APS-C occurs because you're further from the subject for the same framing, and being further away means less magnification.  There's no real penalty for stopping down more on FF, when you factor in DoF and noise, there's really no difference – there are plenty of articles describing the concept of equivalence.  In a nutshell, FF allows shallower DoF if you want it, but there's no penalty for matching the DoF of a smaller sensor. 

The advantage of APS-C for macro shooting is that, as a general rule with most current sensors, the pixel density is higher with APS-C, meaning more pixels on target and higher digital magnification (the amount of benefit depends on the sensors being compared - the D800/a7R  actually put more pixels on target than the recently no-longer-current 12 MP sensor in the T3/1100D, a sensor that actually delivered relatively good noise performance).
Title: Re: Crop sensors better than full frame for macro photography?
Post by: CarlTN on February 24, 2014, 08:50:32 PM
I agree, for macro photography, a crop sensor has the edge.  Unless of course, you're a fan of focus stacking 10 or more images...which I'm not.  A full frame sensor necessarily requires more focus stacking, unless you want your macro images with shallow depth of field...in which case either FF or crop are ok for that.  I don't profess to be a macro expert, though...but I do know that a macro image I shot with an effective 270mm focal length at f/20 on a crop camera, would have needed to be at f/45 or smaller on a full frame sensor, and would have provided 1.6x less magnification to boot.

Sorry, but no - you can't have your cake and eat it, too.  The deeper DoF with APS-C occurs because you're further from the subject for the same framing, and being further away means less magnification.  There's no real penalty for stopping down more on FF, when you factor in DoF and noise, there's really no difference – there are plenty of articles describing the concept of equivalence.  In a nutshell, FF allows shallower DoF if you want it, but there's no penalty for matching the DoF of a smaller sensor. 

The advantage of APS-C for macro shooting is that, as a general rule with most current sensors, the pixel density is higher with APS-C, meaning more pixels on target and higher digital magnification (the amount of benefit depends on the sensors being compared - the D800/a7R  actually put more pixels on target than the recently no-longer-current 12 MP sensor in the T3/1100D, a sensor that actually delivered relatively good noise performance).

Not sorry to you (again get over yourself), and you're the one trying to have your cake and eat it to.  Who said "the same framing"?  I was referring to using THE SAME LENS...as in, the same distance from the subject.  So you can't have your cake and eat it too, by attempting the same "framing" with a macro telephoto lens, which is being used at its minimum focus distance.

And frankly, my 50D put more pixels on the subject than a D800 would have...a FF equivalent 38.5 MP, versus 36.  The 70D would put 5 MP more on subject than that...which again, was already more than the D800.

Most people who do macro photography, use MACRO lenses, in any case.  And sorry but no, with the same 100mm macro lens (for example), a 70D is going to put the full frame equivalent of approximately 50 MP on the subject...but obviously with narrower framing.  You get more detail, more effective magnification, because the pixels are smaller.

You know that, so don't try to frame this as if it doesn't matter, because it does.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: neuroanatomist on February 24, 2014, 09:19:36 PM
Not sorry to you (again get over yourself), and you're the one trying to have your cake and eat it to.  Who said "the same framing"?  I was referring to using THE SAME LENS...as in, the same distance from the subject.  So you can't have your cake and eat it too, by attempting the same "framing" with a macro telephoto lens, which is being used at its minimum focus distance.

Well, in that case you are just plain wrong. If you shoot APS-C and FF at 1:1 and the same f/stop, the APS-C image will have shallower DoF than the FF image.  Not that much shallower, but your contention that APS-C gives deeper DoF than FF under the conditions you just described (same lens, same subject distance) demonstrates that you simply don't understand the relevant concepts.

In addition, you do have to consider subject size.  If you're shooting a subject the size of the APS-C sensor (~15x22 mm) or smaller, you can shoot at 1:1 with either APS-C or FF.  But you can almost frame a quarter at 1:1 with FF (you'll cut off 250 microns), whereas with APS-C at 1:1 you can't even frame a dime.  If you increase distance to frame a subject too large for APS-C, you decrease magnification (and decrease pixels on target - filling the frame with a quarter on a 5DIII at 1:1 puts more pixels on target than filling the frame of a 70D with that same quarter).
Title: Re: Crop sensors better than full frame for macro photography?
Post by: dcm on February 24, 2014, 10:41:58 PM
This somewhat depends on what you are shooting - distance, size and shape.  The bulk of my macro work is on a copy stand with the 100L and 6D or 550D - DOF is less an issue when shooting stamps, photos and other relatively flat objects - F5.6 or F8 is usually sufficient.  The 6D can give me a true 1:1 and handles larger objects better since I don't have to place it farther from the target to frame.  The 6D does much better for this type of work. 
Title: Re: Crop sensors better than full frame for macro photography?
Post by: Mt Spokane Photography on February 25, 2014, 12:48:14 AM
I found that I preferred using my 100L on my 7D for close images of very small creatures to those of my 5D MK II.  The 7D seemed to work really well with that lens.  I wouldn't say that the images were of better quality, but I liked the results better and found it easier to use.  I had excellent results with both, I'd say the photographer is the bigger factor.
 
 
Title: Re: Crop sensors better than full frame for macro photography?
Post by: neuroanatomist on February 25, 2014, 12:59:02 AM
I found that I preferred using my 100L on my 7D for close images of very small creatures to those of my 5D MK II.  The 7D seemed to work really well with that lens.  I wouldn't say that the images were of better quality, but I liked the results better and found it easier to use.  I had excellent results with both, I'd say the photographer is the bigger factor.

I'd say that's often true. 

If you use AF for macro shooting (most don't), AI Servo on the 7D detects Canon macro lenses and uses an algorithm optimized for macro, to compensate for the fore-aft motion. Combined with H-IS of the 100L, not bad.

I do a fair bit of handheld shooting with the MP-E 65mm and MT-24EX.  For that, composition at 4-5x is hard enough with FF - the narrower AoV with a crop sensor makes that even harder.

Speaking of AF, I sometimes wish Canon did trap focus.  I wonder if ML has that feature?
Title: Re: Crop sensors better than full frame for macro photography?
Post by: Marsu42 on February 25, 2014, 02:07:14 AM
What do you think, is really a crop sensor better than full frame for macro photography?

Owning the ff 6d and the crop 60d I do think the latter is better for macro for various reasons, this is my practical experience and I'll keep around the 60d if even for macro alone.

1. Working distance on 100mm lens: If using artificial light or taking shots of something tiny that tends to fly, crawl or jump away this focal length on ff is rather short, I guess that's why they also offer a 180mm... or you put a tc on the lens, but the Kenko has issues with the newer camera's afma and lowers iq a bit.

2. Swivel screen, though that wasn't the question: Only the 60d/70d/Rebels have it, it's invaluable for tripod macro work, esp. when paired with Magic Lantern's focus peaking.

3. Last not least dof (you mentioned it): If you do focus stacking you'll use the lens' best aperture setting before diffraction is an issue, which means many more shots required on ff. If using handheld, a deeper dof = smaller aperture means higher iso, i.e. the iso advantage of ff diminishes.

What might not have been mentioned yet: With ff, you are more likely to run into the macro zone where the usable aperture drops, or the problem is more severe, so that even more (over-)compensates for the iso advantage of ff... the only redeeming fact is that you can better noise-reduce recent ff shots than crop, but still higher iso = less dr. All of the above us for usual firefly to butterfly shooting distances, not for extreme 1:1 which I seldom really require.

With a good lens like the 100L and the current crop resolution, the iq of the lens on crop is about the same as on ff... but of course ff shots have more postprocessing elasticity if you need that.

Speaking of AF, I sometimes wish Canon did trap focus.  I wonder if ML has that feature?

Yes, it does - move the camera until the phase af point detects af lock, then the camera automatically takes the picture. Very handy if you slowly move the lens forward with a fixed focus setting.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: Zv on February 25, 2014, 05:10:04 AM
Take the argument to the extreme and consider something like and iphone 5s. It has a tiny sensor so everything is always in focus. But it still has an f2 lens in terms of light transition. So sometimes I can get a better macro shot in low light on my 5s than I could on my 5d mk iii. Because to get an equivalent depth of field I'd have to stop down to f18 which would push up the ISO to extreme.

I think you have to factor in the difference in sensor size and light gathering capabilities of both. I don't know the exact factor but I would say that the FF sensor would gather a lot more light than the iPhone sensor at the exact same exposure settings. Well that part is obvious but then you see, when you stop the FF / lens aperture down a few stops to match the amount of light you have essentially "bought" yourself a few stops of ISO too. Then another feature of the FF is that even at ultra high ISO it will be relatively noise free and have more detail.

I've never tried macro with an iPhone using only ambient light. I'd imagine you'd need a lot of light. It would be interesting to see a side by side comparison with a 5D3.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: CarlTN on February 25, 2014, 05:28:49 AM
Not sorry to you (again get over yourself), and you're the one trying to have your cake and eat it to.  Who said "the same framing"?  I was referring to using THE SAME LENS...as in, the same distance from the subject.  So you can't have your cake and eat it too, by attempting the same "framing" with a macro telephoto lens, which is being used at its minimum focus distance.

Well, in that case you are just plain wrong. If you shoot APS-C and FF at 1:1 and the same f/stop, the APS-C image will have shallower DoF than the FF image.  Not that much shallower, but your contention that APS-C gives deeper DoF than FF under the conditions you just described (same lens, same subject distance) demonstrates that you simply don't understand the relevant concepts.

In addition, you do have to consider subject size.  If you're shooting a subject the size of the APS-C sensor (~15x22 mm) or smaller, you can shoot at 1:1 with either APS-C or FF.  But you can almost frame a quarter at 1:1 with FF (you'll cut off 250 microns), whereas with APS-C at 1:1 you can't even frame a dime.  If you increase distance to frame a subject too large for APS-C, you decrease magnification (and decrease pixels on target - filling the frame with a quarter on a 5DIII at 1:1 puts more pixels on target than filling the frame of a 70D with that same quarter).

Let me get this straight.  You're saying that a crop sensor will have shallower depth of field than a full frame sensor, given the same subject distance from the lens?  So, if that lens cannot focus at closer than 35 inches (as in the case I described), somehow I'm going to get shallower depth of field with a crop sensor, than with a full frame camera?  Why?  Because the subject is relatively tiny in the center of the (full) frame, and is represented by larger (and thus fewer) pixels over its area?  So what?  I still say with a 100mm macro lens, if ultimate detail and subject magnification is what you want, a crop sensor will be better.  To get the same subject magnification with a full frame camera, the distance will be closer, and then the depth of field will be SHALLOWER than it was with the same framing on the crop camera, not deeper.  It's you who doesn't understand relevant concepts here.  Get off my back.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: CarlTN on February 25, 2014, 05:29:23 AM
I found that I preferred using my 100L on my 7D for close images of very small creatures to those of my 5D MK II.  The 7D seemed to work really well with that lens.  I wouldn't say that the images were of better quality, but I liked the results better and found it easier to use.  I had excellent results with both, I'd say the photographer is the bigger factor.

Nice to see someone can understand where I'm coming from.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: CarlTN on February 25, 2014, 05:30:59 AM
What do you think, is really a crop sensor better than full frame for macro photography?

Owning the ff 6d and the crop 60d I do think the latter is better for macro for various reasons, this is my practical experience and I'll keep around the 60d if even for macro alone.

1. Working distance on 100mm lens: If using artificial light or taking shots of something tiny that tends to fly, crawl or jump away this focal length on ff is rather short, I guess that's why they also offer a 180mm... or you put a tc on the lens, but the Kenko has issues with the newer camera's afma and lowers iq a bit.

2. Swivel screen, though that wasn't the question: Only the 60d/70d/Rebels have it, it's invaluable for tripod macro work, esp. when paired with Magic Lantern's focus peaking.

3. Last not least dof (you mentioned it): If you do focus stacking you'll use the lens' best aperture setting before diffraction is an issue, which means many more shots required on ff. If using handheld, a deeper dof = smaller aperture means higher iso, i.e. the iso advantage of ff diminishes.

What might not have been mentioned yet: With ff, you are more likely to run into the macro zone where the usable aperture drops, or the problem is more severe, so that even more (over-)compensates for the iso advantage of ff... the only redeeming fact is that you can better noise-reduce recent ff shots than crop, but still higher iso = less dr. All of the above us for usual firefly to butterfly shooting distances, not for extreme 1:1 which I seldom really require.

With a good lens like the 100L and the current crop resolution, the iq of the lens on crop is about the same as on ff... but of course ff shots have more postprocessing elasticity if you need that.

Speaking of AF, I sometimes wish Canon did trap focus.  I wonder if ML has that feature?

Yes, it does - move the camera until the phase af point detects af lock, then the camera automatically takes the picture. Very handy if you slowly move the lens forward with a fixed focus setting.

Looks like you also, agree with my point of view.  So I do understand relevant concepts here, and am not just looking to argue and make myself look like an idiot...not this time anyway.  But somebody sure is...
Title: Re: Crop sensors better than full frame for macro photography?
Post by: neuroanatomist on February 25, 2014, 09:02:35 AM
Let me get this straight. You're saying that a crop sensor will have shallower depth of field than a full frame sensor, given the same subject distance from the lens?  So, if that lens cannot focus at closer than 35 inches (as in the case I described), somehow I'm going to get shallower depth of field with a crop sensor, than with a full frame camera?  Why?  Because the subject is relatively tiny in the center of the (full) frame, and is represented by larger (and thus fewer) pixels over its area?  So what?  I still say with a 100mm macro lens, if ultimate detail and subject magnification is what you want, a crop sensor will be better.  To get the same subject magnification with a full frame camera, the distance will be closer, and then the depth of field will be SHALLOWER than it was with the same framing on the crop camera, not deeper.  It's you who doesn't understand relevant concepts here.  Get off my back.
That's exactly what I'm saying - with the same focal length, aperture and subject distance, a crop sensor will have a shallower depth of field.  The 'deeper DoF with a crop sensor' applies only when considering the same framing, where to match the FoV with the smaller sensor you are either further away or using a shorter focal length.  Also, crop sensors don't magnify, they just use a much smaller portion of the image circle (less than 40% of the FF area) - optical magnification of the subject isn't changing. The 'magnification' you're talking about is solely a function of pixel density, which is usually, but not always, higher on crop sensors.  If you frame the subject the same with both formats, the 'advantage' of pixel density is reversed (in general with current sensors). If you keep the distance the same you get more pixels on target with the crop sensor (in general with current sensors) – however, the DoF will be shallower, not deeper...and the smaller pixels of the crop sensor mean a greater effect of diffraction as you stop down, costing you more sharpness.


So I do understand relevant concepts here, and am not just looking to argue and make myself look like an idiot...not this time anyway.  But somebody sure is...
Sorry, but no, you don't.  Don't feel bad, you're not the first to be lost inside the circle of confusion, and you won't be the last.  Instead of calling people names, you could do some reading on the subject, or simply try going to an online depth of field calculator (such as DoFMaster (http://www.dofmaster.com/dofjs.html)), pick a focal length, aperture, and subject distance, then without changing any other settings switch back-and-forth between a full frame body and a crop body in the camera selection, and see which one has the shallower depth of field.  Then you can come back here and tell us who looks like what…
Title: Re: Crop sensors better than full frame for macro photography?
Post by: privatebydesign on February 25, 2014, 09:33:31 AM
The differences between the crop camera and FF camera can be said to have, the same dof, less dof, or more dof depending on your output.

Dof is determined by aperture size and reproduction ratio alone, focal length and subject distance are just parts of the magnification side of the equation, so the output, the final image be it on screen or print is critical in determining dof. All dof calculators assume a same sized output and an average viewing distance, I believe that to be an 8"x10" print (or screen image) viewed at 12" with 20:20 vision.

For a very good explanation look here. http://en.wikipedia.org/wiki/Depth_of_field (http://en.wikipedia.org/wiki/Depth_of_field)

Specifically:-
Quote
Relationship of DOF to format size

The comparative DOFs of two different format sizes depend on the conditions of the comparison. The DOF for the smaller format can be either more than or less than that for the larger format. In the discussion that follows, it is assumed that the final images from both formats are the same size, are viewed from the same distance, and are judged with the same circle of confusion criterion. (Derivations of the effects of format size are given under Derivation of the DOF formulas.)

“Same picture” for both formats
When the “same picture” is taken in two different format sizes from the same distance at the same f-number with lenses that give the same angle of view, and the final images (e.g., in prints, or on a projection screen or electronic display) are the same size, DOF is, to a first approximation, inversely proportional to format size (Stroebel 1976, 139). Though commonly used when comparing formats, the approximation is valid only when the subject distance is large in comparison with the focal length of the larger format and small in comparison with the hyperfocal distance of the smaller format.

Moreover, the larger the format size, the longer a lens will need to be to capture the same framing as a smaller format. In motion pictures, for example, a frame with a 12 degree horizontal field of view will require a 50 mm lens on 16 mm film, a 100 mm lens on 35 mm film, and a 250 mm lens on 65 mm film. Conversely, using the same focal length lens with each of these formats will yield a progressively wider image as the film format gets larger: a 50 mm lens has a horizontal field of view of 12 degrees on 16 mm film, 23.6 degrees on 35 mm film, and 55.6 degrees on 65 mm film. Therefore, because the larger formats require longer lenses than the smaller ones, they will accordingly have a smaller depth of field. Compensations in exposure, framing, or subject distance need to be made in order to make one format look like it was filmed in another format.

Same focal length for both formats
Many small-format digital SLR camera systems allow using many of the same lenses on both full-frame and “cropped format” cameras. If, for the same focal length setting, the subject distance is adjusted to provide the same field of view at the subject, at the same f-number and final-image size, the smaller format has greater DOF, as with the “same picture” comparison above. If pictures are taken from the same distance using the same f-number, same focal length, and the final images are the same size, the smaller format has less DOF. If pictures taken from the same subject distance using the same focal length, are given the same enlargement, both final images will have the same DOF. The pictures from the two formats will differ because of the different angles of view. If the larger format is cropped to the captured area of the smaller format, the final images will have the same angle of view, have been given the same enlargement, and have the same DOF.

Same DOF for both formats
In many cases, the DOF is fixed by the requirements of the desired image. For a given DOF and field of view, the required f-number is proportional to the format size. For example, if a 35 mm camera required f/11, a 4×5 camera would require f/45 to give the same DOF. For the same ISO speed, the exposure time on the 4×5 would be sixteen times as long; if the 35 camera required 1/250 second, the 4×5 camera would require 1/15 second. The longer exposure time with the larger camera might result in motion blur, especially with windy conditions, a moving subject, or an unsteady camera.

Adjusting the f-number to the camera format is equivalent to maintaining the same absolute aperture diameter; when set to the same absolute aperture diameters, both formats have the same DOF.

For a long thread with lots of good imformation, illustrations and links look here http://www.canonrumors.com/forum/index.php?topic=15884.0 (http://www.canonrumors.com/forum/index.php?topic=15884.0)

You have to state what criteria you are using for your output before you can state what effect you are seeing.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: Marsu42 on February 25, 2014, 02:14:17 PM
That's exactly what I'm saying - with the same focal length, aperture and subject distance, a crop sensor will have a shallower depth of field.  The 'deeper DoF with a crop sensor' applies only when considering the same framing

Good we have that sorted out :-) ... and I'm no way intervening between you and good ol' CarlTN, but I'd like to add that the thread title and op makes most sense when considering the same framing, i.e. /me shooting a live firefly with my 100L and getting the vf to match on 6d and 60d. In that case, I'd pick the 60d.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: mackguyver on February 25, 2014, 02:53:31 PM
That's exactly what I'm saying - with the same focal length, aperture and subject distance, a crop sensor will have a shallower depth of field.  The 'deeper DoF with a crop sensor' applies only when considering the same framing

Good we have that sorted out :-) ... and I'm no way intervening between you and good ol' CarlTN, but I'd like to add that the thread title and op makes most sense when considering the same framing, i.e. /me shooting a live firefly with my 100L and getting the vf to match on 6d and 60d. In that case, I'd pick the 60d.
To take an even further step back, I would say that the crop vs. FF argument for macro is no different than it is for other genres of photography.  Crop will give you more perceived magnification (via cropping) at the same lens-to-subject distance just as it would for wildlife or anything else.  FF cameras offer better quality (sharpness) at the pixel level and better performance at high ISO.   This last point is important if you shoot with natural light because as you increase magnification you lose light and the more a slight wind will seem like a hurricane.  To shoot flowers in soft light with a light breeze at 1:1, you'll often need to be at ISO 1600-3200 just to get 1/30s which is the bare minimum for most subjects.  Got to 2:1 and it gets even worse.  That's where the FF bodies can give you an advantage.  If you shoot timid or dangerous subjects, crop will give you extra working distance for the same framing, giving an advantage.

Both types of cameras will give you great macro shots, and if you look at some of my 70+ macro shots in the gallery below, you'll be hard pressed to tell what was shot with a crop vs. full frame without looking at the EXIF, which is in the "Show Details" tab.  With macro, technique will Me_Me_Me equipment for most people, so the best bet is just go out there and shoot :)
http://www.ianandersonphotography.com/Other/InBloom/32974529_HgZgN5#!i=2857799475&k=8bfmgKj (http://www.ianandersonphotography.com/Other/InBloom/32974529_HgZgN5#!i=2857799475&k=8bfmgKj)
Title: Re: Crop sensors better than full frame for macro photography?
Post by: privatebydesign on February 25, 2014, 03:09:50 PM
Ok,

I accept actually reading an entire article that explains everything in a few pages is too much for practically everybody, and shouting your ignorance at the top of your voice is far more fun (Carl!). So here is a concise version.

If you can get the framing you want with the lens you have with either camera the FF camera will give you the better image. You will have more pixels on target and any adjustment needed to match dof because the camera is closer can be done with iso for a neutral noise and dof equation.

If you can get the framing you want with the crop camera but not the ff one (you can't get close enough and/or the subject is too small), the crop camera will give you the better image. But only because the crop camera will put more pixels on target, if you crop the ff image to match the crop camera image the dof, noise, and everything else is identical.

These two examples assume you need the maximum amount of pixels on target, if you don't, and most of us don't 99.9999999999% of the time, there will be very little difference between the two. In most real world shooting, including macro, a ff camera will best a crop camera at everything to do with image output quality, the reasons for this are many and varied, but who, for instance, accepts that a crop camera needs over 1.6 times the support of a ff camera? Yep. you should use a more expensive and sturdier tripod for your smaller sensor. Equivalence needs to take shutters speed into account where you are limited by hand holding not subject motion, but it doesn't, this is very relevant to macro shooting. Most of the time these differences are small enough to not impact the average output.

People that think a crop camera gives you anything for free are sadly mistaken. You don't get "free" reach, dof, noise, or any other quantifiable image metric from using a crop camera.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: Marsu42 on February 25, 2014, 03:31:52 PM
People that think a crop camera gives you anything for free are sadly mistaken. You don't get "free" reach, dof, noise, or any other quantifiable image metric from using a crop camera.

I'd disagree in one select special case, and that happens to be a macro situation... but please correct me if I'm getting it wrong:

If you have the same framing on crop and ff, the ff nears to the subject (the famed working distance). If the crop is still outside the macro distance and can use the full aperture, and the ff is inside it (meaning the usable aperture drops to rock bottom) the ff needs to use a *higher* iso setting to get the *same* exposure - that's how macro lenses work if you increase magnification and the macro mechanism is engaged.

This effect means that depending on the lens-object distance, the crop camera has less noise disadvantage than usual, or it might even have an advantage - the latter is my personal, subjective experience and part of the reason why I'd prefer to shoot fireflies with crop.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: privatebydesign on February 25, 2014, 03:45:22 PM
People that think a crop camera gives you anything for free are sadly mistaken. You don't get "free" reach, dof, noise, or any other quantifiable image metric from using a crop camera.

I'd disagree in one select special case, and that happens to be a macro situation... but please correct me if I'm getting it wrong:

If you have the same framing on crop and ff, the ff nears to the subject (the famed working distance). If the crop is still outside the macro distance and can use the full aperture, and the ff is inside it (meaning the usable aperture drops to rock bottom) the ff needs to use a *higher* iso setting to get the *same* exposure - that's how macro lenses work if you increase magnification and the macro mechanism is engaged.

This effect means that depending on the lens-object distance, the crop camera has less noise disadvantage than usual, or it might even have an advantage - the latter is my personal, subjective experience and part of the reason why I'd prefer to shoot fireflies with crop.

I'm sorry I don't understand this bit "If the crop is still outside the macro distance and can use the full aperture, and the ff is inside it (meaning the usable aperture drops to rock bottom)"

If the two cameras are at different distances for the same framing the crop camera aperture number will be lower to get the same shot. If they are both wide open the dof of the ff camera will be less but it will gather over twice as much light on it's over twice as large sensor, this will result in less noise. So stop the ff camera down and raise the iso to get the same noise (but even then the ff camera actually comes out better) for the same dof.

The only situation where you can't do dof equivalence is stopping right down, if your crop camera is at f32 you can't (with most lenses) stop down to f64 for the ff shot, but you have long since passed the limits of diffraction and would be better off focus stacking anyway.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: neuroanatomist on February 25, 2014, 04:04:03 PM
If you have the same framing on crop and ff, the ff nears to the subject (the famed working distance). If the crop is still outside the macro distance and can use the full aperture, and the ff is inside it (meaning the usable aperture drops to rock bottom) the ff needs to use a *higher* iso setting to get the *same* exposure - that's how macro lenses work if you increase magnification and the macro mechanism is engaged.

This effect means that depending on the lens-object distance, the crop camera has less noise disadvantage than usual, or it might even have an advantage - the latter is my personal, subjective experience and part of the reason why I'd prefer to shoot fireflies with crop.

I'm sorry I don't understand this bit "If the crop is still outside the macro distance and can use the full aperture, and the ff is inside it (meaning the usable aperture drops to rock bottom)"

I suspect what Marsu42 is referring to is the decrease apparent aperture, the light loss you get as magnification increases.  There's no 'magic number' for that, there's no 'macro mechanism', and it's not the case that 'outside macro distance' there's no light lost.  At 0.2x mag you lose ~0.67-stops of light, at 0.5x mag you lose ~1.33-stops, and at 1x you lose ~2-stops.  The decrease in magnification when matching framing means a differential loss of less than 2/3-stop more with the FF sensor at 1:1, and that's likely not enough to make a significant difference, particularly since recent FF bodies tend to give more than the size-predicted 1.33-stop noise benefit over APS-C. 
Title: Re: Crop sensors better than full frame for macro photography?
Post by: privatebydesign on February 25, 2014, 04:12:35 PM
Ok, the old extension tube bellows light loss thing. Yes, as you say, because the ff tends to outperform the numbers I would expect the same thing, the ff camera would still give a "better" image.

Back in my film days I actually used to know how to work all that out, my class project was to take a picture of a hand on a watch face, I filled the (FF) image with the width of the minute hand, I used two sets of bellows at full extension and either a 50mm or 32mm lens. But that was a long time ago.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: faustino on February 25, 2014, 04:25:41 PM
I would like to thank you all for your replies.

At this point I feel the duty to summarize my learnings from your posts:

For macro photography, there are two meaningful ways to compare crop vs. full frame sensors:

1)
The comparison can be made trying to achieve the same image in terms of perspective and depth of field.
* In order to get the same image in terms of perspective (related to distance) and framing, the smaller sensor shall be coupled with a shorter lens. If we put a 100mm lens on the full frame, something in the range of 60mm lens should be mounted on the crop sensor camera (assuming a 1.6 crop factor).
* In order to get the same depth of field, the aperture on the full frame camera shall be roughly one stop smaller. The smaller aperture would loose one stop of light, that would be compensated by the "one stop higher" light gathering capacity of full frame sensors.
* Identical framing is achieved with the same distance to the subject.
==> In such first comparison the output from the two setup is theoretically very similar. Anyhow, in practice, as pointed out by Neuro and proved by Mackguyver, the image from the full frame sensor would be visibly sharper. Since there is a proof, I would say this conclusion is incontrovertible.

2)
The comparison can be made keeping the same lens on both full frame and crop camera.
In this case the distance to the subject can be either be selected to be the same (2.1), or we can move the crop camera further away (2.2) to get some sort of "same composition" (will never be the same composition because perspective would be different)

2.1) keeping the same distance:
The crop sensor would capture exactly the same image that would be obtained from the full frame sensor cropping in post production.
==> The advantage of crop camera would be in pixel count, allowing more latitude for further cropping (if ISO is not pushed up too much) - as Neuro was writing elsewhere, the subject image is captured with more pixels.
==> The advantage of the full frame would be a larger angle of view, which is potentially important for multiple reasons (e.g. easiness of composition)

2.2) moving the crop camera further away from the subject.
Such scenario would could be considered less important; a full frame owner could move his camera further away as well, then crop in post production, and get the same image that could be obtained by an APS-C camera owner (except from pixel count).

In this latter scenario (2.1 and 2.2), the crop camera have actually the advantage of capturing the same cropped image that a full frame camera can capture, but with more pixels (usually it is the case with current cameras, may not be true with future cameras). This is unquestionable an advantage, if the ISO is "low". It is not and advantage, and can be a disadvantage, if the ISO needs to be pushed up.

Besides the above, there are some advantages of current crop cameras that I am not considering, e.g. swivel screen, weight, and some sort of better autofocus (7d coupled with 100mm f2.8L IS USM).
Title: Re: Crop sensors better than full frame for macro photography?
Post by: CarlTN on February 25, 2014, 08:54:03 PM
==> The advantage of crop camera would be only in pixel count, which is a questionable advantage.

Questionable how?  Not from the standpoint of putting pixels on the subject.  50MP vs. 22 is quite a difference.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: CarlTN on February 25, 2014, 09:02:50 PM
Let me get this straight. You're saying that a crop sensor will have shallower depth of field than a full frame sensor, given the same subject distance from the lens?  So, if that lens cannot focus at closer than 35 inches (as in the case I described), somehow I'm going to get shallower depth of field with a crop sensor, than with a full frame camera?  Why?  Because the subject is relatively tiny in the center of the (full) frame, and is represented by larger (and thus fewer) pixels over its area?  So what?  I still say with a 100mm macro lens, if ultimate detail and subject magnification is what you want, a crop sensor will be better.  To get the same subject magnification with a full frame camera, the distance will be closer, and then the depth of field will be SHALLOWER than it was with the same framing on the crop camera, not deeper.  It's you who doesn't understand relevant concepts here.  Get off my back.
That's exactly what I'm saying - with the same focal length, aperture and subject distance, a crop sensor will have a shallower depth of field.  The 'deeper DoF with a crop sensor' applies only when considering the same framing, where to match the FoV with the smaller sensor you are either further away or using a shorter focal length.  Also, crop sensors don't magnify, they just use a much smaller portion of the image circle (less than 40% of the FF area) - optical magnification of the subject isn't changing. The 'magnification' you're talking about is solely a function of pixel density, which is usually, but not always, higher on crop sensors.  If you frame the subject the same with both formats, the 'advantage' of pixel density is reversed (in general with current sensors). If you keep the distance the same you get more pixels on target with the crop sensor (in general with current sensors) – however, the DoF will be shallower, not deeper...and the smaller pixels of the crop sensor mean a greater effect of diffraction as you stop down, costing you more sharpness.


So I do understand relevant concepts here, and am not just looking to argue and make myself look like an idiot...not this time anyway.  But somebody sure is...
Sorry, but no, you don't.  Don't feel bad, you're not the first to be lost inside the circle of confusion, and you won't be the last.  Instead of calling people names, you could do some reading on the subject, or simply try going to an online depth of field calculator (such as DoFMaster (http://www.dofmaster.com/dofjs.html)), pick a focal length, aperture, and subject distance, then without changing any other settings switch back-and-forth between a full frame body and a crop body in the camera selection, and see which one has the shallower depth of field.  Then you can come back here and tell us who looks like what…

What names did I call anyone?

What you are saying, does not make sense with the experience I have had.  For example, a wide angle lens.  How is it that I have to use a smaller aperture on a wide angle lens on a full frame camera, to get the same depth of field, as with an aps-c camera?  For example, a 24mm lens closed to f/5.6 on a full frame camera, has much shallower depth of field on a full frame sensor, as does a 15mm lens closed to the same aperture on a Canon aps-c camera.  You're going to say this isn't true also?

When I look through the viewfinder, even my own eye (which is seeing deeper depth of field than the full frame sensor does)...seems to see far less "deep focus" with say my 58mm Voigtlander f/1.4 lens (even though the angle of view is wider on the full frame)...than it did on the previous crop camera I had.

How is it that a compact camera with a tiny sensor, can get very deep focus (within its angle of view) even when zoomed into a full frame equivalent of 300mm, at an aperture of only say f/6.3...whereas if I put a 300mm lens on my 6D, I need to close it to f/20 or smaller to get a similar "deep focus"??

 
Title: Re: Crop sensors better than full frame for macro photography?
Post by: CarlTN on February 25, 2014, 09:06:04 PM
If you can get the framing you want with the lens you have with either camera the FF camera will give you the better image. You will have more pixels on target and any adjustment needed to match dof because the camera is closer can be done with iso for a neutral noise and dof equation.

Who's calling names now?  You're calling me ignorant, and you're also falsely accusing me of shouting at the top of my lungs....THIS IS SHOUTING DUDE...not this...

You can't actually get more pixels on subject if the pixel count is the same, as in a 70D vs 6D, both have 20 MP.  22 MP isn't that much more pixels...and in any case I have my doubts at your prowess of being a macro photographer.  Is that supposed to be your specialty?  If so I wasn't aware of it.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: neuroanatomist on February 25, 2014, 09:21:47 PM
What names did I call anyone?

Insult by implication is still insult. 

On the off chance that you're actually interested in the understanding the relevant concepts...

What you are saying, does not make sense with the experience I have had.  For example, a wide angle lens.  How is it that I have to use a smaller aperture on a wide angle lens on a full frame camera, to get the same depth of field, as with an aps-c camera?  For example, a 24mm lens closed to f/5.6 on a full frame camera, has much shallower depth of field on a full frame sensor, as does a 15mm lens closed to the same aperture on a Canon aps-c camera.  You're going to say this isn't true also?

If you're comparing a 24mm lens on FF to a 15mm lens on APS-C, of course the DoF will be deeper with APS-C at the same aperture.  The shorter focal length means less subject magnification, it's the same as increasing the distance in term of effect on DoF.

When I look through the viewfinder, even my own eye (which is seeing deeper depth of field than the full frame sensor does)...seems to see far less "deep focus" with say my 58mm Voigtlander f/1.4 lens (even though the angle of view is wider on the full frame)...than it did on the previous crop camera I had.

First off, your viewfinder is showing you the DoF of ~f/2.5-2.8 with the stock viewfinder.  You only see the true DoF of faster lenses if you have installed an appropriate focusing screen (such as the Eg-S). 

But while I know the technical reasons for what you should be seeing, I really have no idea what you're actually seeing…  If I had to guess, you're comparing the same framing - being further away with APS-C means deeper DoF.

How is it that a compact camera with a tiny sensor, can get very deep focus (within its angle of view) even when zoomed into a full frame equivalent of 300mm, at an aperture of only say f/6.3...whereas if I put a 300mm lens on my 6D, I need to close it to f/20 or smaller to get a similar "deep focus"??

Focal length again.  When 'zoomed into a full frame equivalent of 300mm,' what's the real focal length of the lens?  For example, if that compact camera is the SX50, the FF equivalent of 300mm is a real 53mm lens.  The DoF is determined by the actual focal length of the lens, not the FF equivalent of that focal length.  Compare the DoF of a 50mm lens on your 6D with a 300mm lens on your 6D, at the same subject distance.  Which has the deeper DoF?
Title: Re: Crop sensors better than full frame for macro photography?
Post by: Hillsilly on February 25, 2014, 11:23:15 PM
....At this point I feel the duty to summarize my learnings from your posts...

That's a good summary.  Overall, it is difficult to argue that crop sensors will produce a better image than a full frame sensor.  But given that we're on page 3 with vocal proponents on each side and the "Full Frame vs Crop Sensor" topic is up to page 13, you could take that to mean that a crop sensor will produce excellent results and that you will probably only notice a difference if comparing two images side by side.  In the real world, where an image stands on its own, a crop sensor produces images that are more than acceptable to everyone.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: Marsu42 on February 26, 2014, 01:28:02 AM
I suspect what Marsu42 is referring to is the decrease apparent aperture, the light loss you get as magnification increases.

Indeed, but it's not "apparent" but for real, unlike Nikon Canon just chose to hide the fact that a f2.8 lens @1:1 doesn't get f2.8 light through anymore... that's why the shutter speed gets longer like by black magic. I just read up about it again, it's called "effective f-stop": http://www.cambridgeincolour.com/tutorials/macro-lenses.htm (http://www.cambridgeincolour.com/tutorials/macro-lenses.htm)

There's no 'magic number' for that, there's no 'macro mechanism'

Imho there is, it's the "extension" that only a real macro lens has.

At 0.2x mag you lose ~0.67-stops of light, at 0.5x mag you lose ~1.33-stops, and at 1x you lose ~2-stops.

Ah, thanks, that were exactly the numbers I was looking for. Now I'd only need to calculate how much effective f-stop difference there is for crop vs. ff for some scenes, but what you wrote indicates ff still has a slight advantage, though to a much smaller degree than at non-macro distances. But *plus* you still need a smaller aperture to get a usable dof, so that means even higher iso on ff for the same framing.

That, the dr loss at the higher iso for ff, the working distance & swivel screen still make me use the 60d :-)
Title: Re: Crop sensors better than full frame for macro photography?
Post by: CarlTN on February 26, 2014, 01:40:25 AM
Insult by implication is still insult. 

What the hell?  Um, Dr. John…you of all people should know you’re guilty of the above, especially in my case (but in the case of most people you get on your high horse with on here), if not outright insults…many many times over on this forum.  So let’s call a spade a spade.  People in glass houses…Mr. "I'm so smart I will make a cartoon character out of you in pink tights, but no that is not an insult, because I said so, and I own this website".


First off, your viewfinder is showing you the DoF of ~f/2.5-2.8 with the stock viewfinder.  You only see the true DoF of faster lenses if you have installed an appropriate focusing screen (such as the Eg-S). 

But while I know the technical reasons for what you should be seeing, I really have no idea what you're actually seeing…  If I had to guess, you're comparing the same framing - being further away with APS-C means deeper DoF.

I know the reason too, and it's not all that technical.  The reason I'd need a focusing screen, is because my pupil is much smaller than the sensor.  Sure there is more to it than that (the path reflected through the prism and magnified by the eyepiece, etc)...but that's the gist of it. 

In any case, my original point is something you have done your best to ignore.  I was not arguing so much that equal framing with the two sensor sizes would produce superior results with a crop sensor.  I was arguing that you get more effective magnification due to the smaller pixels of the crop sensor...WITH THE SAME LENS and same distance to the subject.  I.E., regardless of whether the framing is "ideal" with either sensor size...just given the same lens...one that perhaps cannot focus on a subject that is touching the front lens element...but rather needs inches or a foot or three distance from the element.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: faustino on February 26, 2014, 03:19:38 AM
==> The advantage of crop camera would be only in pixel count, which is a questionable advantage.

Questionable how?  Not from the standpoint of putting pixels on the subject.  50MP vs. 22 is quite a difference.

I agree, it is not that much questionable. I changed my mind about this specific point, and changed my previous post accordingly.

There is only one consideration about pixel count that I believe should be taken in account:
at higher ISO, considering current sensor technology, lower pixel count sensors produce better images than higher pixel count sensors.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: wsheldon on February 26, 2014, 08:20:21 AM
==> The advantage of crop camera would be only in pixel count, which is a questionable advantage.

Questionable how?  Not from the standpoint of putting pixels on the subject.  50MP vs. 22 is quite a difference.

I agree, it is not that much questionable. I changed my mind about this specific point, and changed my previous post accordingly.

There is only one consideration about pixel count that I believe should be taken in account:
at higher ISO, considering current sensor technology, lower pixel count sensors produce better images than higher pixel count sensors.

True, but we're talking about macro here where tripods and low ISO are the order of the day. At ISO 100 I'm very happy with the IQ of the 15MPx covering the subject from my 50D at 100mm, and the extra working distance compared to my 6D is extremely helpful when shooting critters and flowers.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: faustino on February 26, 2014, 08:35:49 AM
==> The advantage of crop camera would be only in pixel count, which is a questionable advantage.

Questionable how?  Not from the standpoint of putting pixels on the subject.  50MP vs. 22 is quite a difference.

I agree, it is not that much questionable. I changed my mind about this specific point, and changed my previous post accordingly.

There is only one consideration about pixel count that I believe should be taken in account:
at higher ISO, considering current sensor technology, lower pixel count sensors produce better images than higher pixel count sensors.

True, but we're talking about macro here where tripods and low ISO are the order of the day. At ISO 100 I'm very happy with the IQ of the 15MPx covering the subject from my 50D at 100mm, and the extra working distance compared to my 6D is extremely helpful when shooting critters and flowers.

I agree about low ISO being the order of the day, also because, most probably, flashes are engaged beside good tripods.

My understanding is that the advantage of todays camera crop sensors is only pixel density (beside price, weight, and swivel screens). Right?
Title: Re: Crop sensors better than full frame for macro photography?
Post by: neuroanatomist on February 26, 2014, 09:09:56 AM
==> The advantage of crop camera would be only in pixel count, which is a questionable advantage.
Questionable how?  Not from the standpoint of putting pixels on the subject.  50MP vs. 22 is quite a difference.
Questionable based on whether or not you need those MP for your desired output.  An 8 MP image (current FF cropped to the APS-C FoV) is fine for prints of up to 16x24"/A2 size, and overkill for web uploads. 

Of course, if you get your jollies by viewing images at 100% on your display, then more MP is a big advantage.  But if that's the case, you'd better have the largest, highest-resolution display money can buy, or else you're not getting the most benefit from those extra pixels.   ::)

As PBD pointed out above, most people don't need those extra MP.  Not that having them is a bad thing, but it's really about the output.


First off, your viewfinder is showing you the DoF of ~f/2.5-2.8 with the stock viewfinder.  You only see the true DoF of faster lenses if you have installed an appropriate focusing screen (such as the Eg-S). 

But while I know the technical reasons for what you should be seeing, I really have no idea what you're actually seeing…  If I had to guess, you're comparing the same framing - being further away with APS-C means deeper DoF.

I know the reason too, and it's not all that technical.  The reason I'd need a focusing screen, is because my pupil is much smaller than the sensor.  Sure there is more to it than that (the path reflected through the prism and magnified by the eyepiece, etc)...but that's the gist of it. 
The reason you don't see the true DoF of fast lenses is that the stock focus screen is laser microetched to give a brighter viewfinder with slow lenses (presumably because most camera kits come with a zoom that goes to f/5.6, and even the higher end FF kits come with an f/4 lens).  The consequence of that laser microetching is that the true DoF of lenses faster than f/4 is not seen, although the effect is really only noticable as you get faster than f/2.8.  Another case of 'you can't have your cake and eat it, too.'


In any case, my original point is something you have done your best to ignore.  I was not arguing so much that equal framing with the two sensor sizes would produce superior results with a crop sensor.  I was arguing that you get more effective magnification due to the smaller pixels of the crop sensor...WITH THE SAME LENS and same distance to the subject.  I.E., regardless of whether the framing is "ideal" with either sensor size...just given the same lens...one that perhaps cannot focus on a subject that is touching the front lens element...but rather needs inches or a foot or three distance from the element.
Your original point is something that you're conveniently forgetting.  So, I'll remind you: your point was that a crop sensor is better because you get deeper DoF.  In your first post in this thread (http://www.canonrumors.com/forum/index.php?topic=19747.msg372323#msg372323) you stated,  "...a crop sensor has the edge.  Unless of course, you're a fan of focus stacking 10 or more images...which I'm not.  A full frame sensor necessarily requires more focus stacking, unless you want your macro images with shallow depth of field...

In fact, the person who first mentioned the advantage of APS-C putting more pixels on target was…me.  Initially in a post (http://www.canonrumors.com/forum/index.php?topic=19747.msg372187#msg372187) quoting myself from another thread, then directly in response to you (http://www.canonrumors.com/forum/index.php?topic=19747.msg372381#msg372381).  But now you're rewriting history in your own mind, and claiming credit for the idea?  That doesn't work so well when everyone can just read the earlier posts in this thread to see that you're wrong. 

The fact remains that you were completely wrong in your statement that a crop sensor has an advantage in terms of deeper DoF under the conditions you describe (same lens, same distance).  As least now I understand why the SuperCarl graphic upsets you so much - you're 'manly' enough that the idea of wearing pink tights is anathema to you…you're just not man enough to admit that you're wrong, at least in this case.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: neuroanatomist on February 26, 2014, 09:26:17 AM
I suspect what Marsu42 is referring to is the decrease apparent aperture, the light loss you get as magnification increases.

Indeed, but it's not "apparent" but for real, unlike Nikon Canon just chose to hide the fact that a f2.8 lens @1:1 doesn't get f2.8 light through anymore... that's why the shutter speed gets longer like by black magic. I just read up about it again, it's called "effective f-stop": http://www.cambridgeincolour.com/tutorials/macro-lenses.htm (http://www.cambridgeincolour.com/tutorials/macro-lenses.htm)
What's your point?  'Effective f-stop' and 'apparent aperture' mean the same thing.  The light loss is real, but the physical aperture is not changing size.  You can't say f/2.8 becomes f/5.6 at 1:1, any more than you can say that an EF 100mm lens becomes a 160mm lens when you mount it on a crop body.

If you're using a Nikon camera in Av mode and go to 1:1 magnification, the shutter speed doesn't change and you get shots underexposed by 2 stops?   :o  I didn't know that, but if true I don't think that makes sense.  An autoexposure mode should give me a metered exposure, period.  Therefore, I'd expect it to compensate for the light lost at 1:1 by altering the shutter speed (and/or ISO, if that was set to Auto).

Also, I'm not sure why you state, "Canon just chose to hide the fact that a f2.8 lens @1:1 doesn't get f2.8 light through anymore."  That's a pretty bold and unsupported accusation.  Unless you think they're trying to hide that imformation in plain sight…such as by printing it right in the instruction manual for the lens.   ::)
Title: Re: Crop sensors better than full frame for macro photography?
Post by: mackguyver on February 26, 2014, 09:31:48 AM
I suspect what Marsu42 is referring to is the decrease apparent aperture, the light loss you get as magnification increases.

Indeed, but it's not "apparent" but for real, unlike Nikon Canon just chose to hide the fact that a f2.8 lens @1:1 doesn't get f2.8 light through anymore... that's why the shutter speed gets longer like by black magic. I just read up about it again, it's called "effective f-stop": http://www.cambridgeincolour.com/tutorials/macro-lenses.htm (http://www.cambridgeincolour.com/tutorials/macro-lenses.htm)
What's your point…'effective f-stop' and 'apparent aperture' mean the same thing.  The light loss is real, but the physical aperture is not changing size.  You can't say f/2.8 becomes f/5.6 at 1:1, any more than you can say that an EF 100mm lens becomes a 160mm lens when you mount it on a crop body.

If you're using a Nikon camera in Av mode and go to 1:1 magnification, the shutter speed doesn't change and you get shots underexposed by 2 stops?   :o  I didn't know that, but if true I don't think that makes sense.  An autoexposure mode should give me a metered exposure, period.  Therefore, I'd expect it to compensate for the light lost at 1:1 by altering the shutter speed (and/or ISO, if that was set to Auto).

Also, I'm not sure why you state, "Canon just chose to hide the fact that a f2.8 lens @1:1 doesn't get f2.8 light through anymore."  That's a pretty bold and unsupported accusation.  Unless you think they're trying to hide that imformation in plain sight…such as by printing it right in the instruction manual for the lens.   ::)
Neuro, I remember reading that there is a difference in the way Nikon displays the light loss vs. Canon (in one of Scott Kelby's books, I think), but at the end of the day, exposure is exposure, and the light loss (and the need for high ISOs when shooting in natural light) is the main reason I think that FF is better than crop for macro, at least for my needs.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: Marsu42 on February 26, 2014, 09:42:39 AM
0
If you're using a Nikon camera in Av mode and go to 1:1 magnification, the shutter speed doesn't change you get shots underexposed by 2 stops?

Nope, afaik they simply show the effective f-stop, and then you know why the shutter speed suddenly gets longer.

0
Also, I'm not sure why you state, "Canon just chose to hide the fact that a f2.8 lens @1:1 doesn't get f2.8 light through anymore."  That's a pretty bold and unsupported accusation.  Unless you think they're trying to hide that imformation in plain sight…such as by printing it right in the instruction manual for the lens.   

I'm not trying to pick a fight, if you need some mudslinging go talk to some well-known contributor who responds to that. But I'm as a simple Canon beginner didn't understand (and even realize) the problem at macro distances, and only wondered why I ran into such low shutter or high iso values. Yes, rtfm, but still.

Simply giving the effective f-stop rather than the nominal value makes more sense to me, and everything else is "hiding" not in a moral sense, but as a loss of potential information.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: neuroanatomist on February 26, 2014, 09:54:45 AM
0
If you're using a Nikon camera in Av mode and go to 1:1 magnification, the shutter speed doesn't change you get shots underexposed by 2 stops?
Nope, afaik they simply show the effective f-stop, and then you know why the shutter speed suddenly gets longer.

So, you'd prefer that the camera report an aperture that is not the one you selected, whereas I'd prefer that the camera show the selected aperture and adjust the exposure to compensate. 

It's not a moral issue, which calling it 'hiding' implies.  Rather, Canon and Nikon have simply chosen different ways to represent the loss of light at high magnification. 

As a side note, that must mean a Nikon camera will display an aperture value that is smaller than the lens is physically capable of achieving.  So if we're going to make it a moral issue, Canon is hiding something, and Nikon is lying about something else.   ;)


There's no 'magic number' for that, there's no 'macro mechanism'

Imho there is, it's the "extension" that only a real macro lens has.

The EF-S 18-55mm f/3.5-5.6 IS STM has a maximum magnification of 0.36x, and at that magnification it is losing ~1 stop of light based on the narrower apparent aperture (or smaller effective f-stop, if you prefer that terminology).  I wouldn't call the Rebel kit lens a 'real macro lens'...


That, the dr loss at the higher iso for ff, the working distance & swivel screen still make me use the 60d :-)

You seem to be ignoring the fact that the APS-C sensor has less DR than the FF sensor, at all ISO settings. 

ISO 800 on the 6D has the same DR as ISO 100 on the 60D - a 3-stop advantage for the FF sensor.  At ISO 400 and above on the 60D, the 6D has approximately the same DR at a 2-stop higher ISO setting.  Where is the DR advantage of the APS-C sensor? 

Swivel screen?  Canon's free EOS Remote app allows remote live view from the 6D, and may be more useful than a swivel screen.  Granted, the 6D is the only Canon FF camera with Wi-Fi (so far)…but there's also CamRanger for the others.

As for the working distance advantage, that's the same argument for why APS-C is better when you're focal length limited in telephoto situations.  It's only an advantage if you require more than ~8 MP for your output (i.e. you're printing larger than 16x24"/A2) and you're shooting at relatively low ISO.  For normal and small prints, web use, or if you have to boost the ISO, the cropped FF image will be as good or better.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: neuroanatomist on February 26, 2014, 10:04:05 AM
Overall, it is difficult to argue that crop sensors will produce a better image than a full frame sensor.

From the standpoint of IQ, yes.  However…I'd argue that a crop sensor camera that one can afford will produce much better images than the full frame camera that one cannot afford. 

IMO, the only real and significant advantage of the APS-C sensor is that crop bodies are cheaper.  In many cases and for many people, that advantage trumps all other considerations.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: Marsu42 on February 26, 2014, 10:17:22 AM
ISO 800 on the 6D has the same DR as ISO 100 on the 60D - a 3-stop advantage for the FF sensor.

Ah, you're comparing a 2012 camera to a 2010 camera. Let me counter this: The 7d has more dr at iso 800 than the 5dc, giving crop a solid 2-stop advantage over the FF sensor :-> ... the dr argument is just a side note, it just happens to add up with the fact that the ff advantage is less than usual for macro.


Swivel screen?  Canon's free EOS Remote app allows remote live view from the 6D, and may be more useful than a swivel screen.

Yeah, right, *may* ... but to anyone doing serious macro tripod work it isn't, but I understand you missing out on this because your cameras don't have it so you never really tried. Wifi+Phone requires another gadget and draws power, and unless someone reverse engineers the protocol you cannot use focus peaking nor focus stacking with it. Nice tourist selfie feature mind you or for photo journalism, but certainly not for macro.

As for the working distance advantage, that's the same argument for why APS-C is better when you're focal length limited in telephoto situations.  It's only an advantage if you require more than ~8 MP for your output (i.e. you're printing larger than 16x24"/A2) and you're shooting at relatively low ISO.  For normal and small prints, web use, or if you have to boost the ISO, the cropped FF image will be as good or better.

I don't think so, first because cropping even the crop shot is usual if limited by the 1:1 mag, so you'll end up with even less mp on ff - I share your opinion for tele photography, but not for macro. Plus as discussed the iso advantage of ff is a bit less than usual because of the effective f-stop and shallower dof (same framing).

For normal and small prints, web use, or if you have to boost the ISO, the cropped FF image will be as good or better.

We have to agree to disagree here unless someone comes up with actual side by side comparisons :-o
Title: Re: Crop sensors better than full frame for macro photography?
Post by: neuroanatomist on February 26, 2014, 10:40:57 AM
ISO 800 on the 6D has the same DR as ISO 100 on the 60D - a 3-stop advantage for the FF sensor.

Ah, you're comparing a 2012 camera to a 2010 camera. Let me counter this: The 7d has more dr at iso 800 than the 5dc, giving crop a solid 2-stop advantage over the FF sensor :-> ... the dr argument is just a side note, it just happens to add up with the fact that the ff advantage is less than usual for macro.

Ok, let's compare the 6D from 2012 to the newer 70D from 2013 - the latter is basically the same as the 60D from a DR standpoint.  Still no DR advantage for APS-C.

We have to agree to disagree here unless someone comes up with actual side by side comparisons :-o

Fair enough.   :D
Title: Re: Crop sensors better than full frame for macro photography?
Post by: AmazonOfExeter on February 26, 2014, 06:51:49 PM
Hello!
Have been reading the thread with great interest, and trying to keep up with the information!

Just to add a comment in relation to Marsu42 and Neuros' thoughts on swivel screens/remote viewing for macro work (or other work too).

In favour of the swivel screen is the fact it is attached and easily manipulated, not easily lost and rapidly deployed.

In favour of a remote viewing is, if you use DSLR Controller then you have the advantage of a larger screen (dependent on the device  - currently using a Sony Z1 phone to test it on, more or less a 5'' screen), in theory a very good range of distances and angles to see it from, plus the ability to completely control the camera from the screen - including focus peaking. On the downside, it is very fiddly unless you have some sort of bracket made up to carry the device (potentially reducing the flexibility of the solution) and if, like me, you tend to be trying to photograph subjects that are constantly moving, this bracket idea is essential unless you have 3 hands...! I've not really explored all that DSLR controller can do, and I haven't installed Magic Lantern (tempted but...) so I cannot compare the quality or abilities of the two systems!

Hope this helps! Thank you for the great information!
Title: Re: Crop sensors better than full frame for macro photography?
Post by: CarlTN on February 26, 2014, 09:28:12 PM
My post was deleted but I sent it to you privately, neuro.

I can see this argument must now end, because well...anything else I say is going to get deleted anyway.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: neuroanatomist on February 26, 2014, 11:16:34 PM
My post was deleted but I sent it to you privately, neuro.

I can see this argument must now end, because well...anything else I say is going to get deleted anyway.

Yes, I can see why it was deleted.

"Insults are the arguments employed by those who are in the wrong."  —Jean-Jacques Rousseau


But in the "macro" world, you're taking a picture of something that is tiny.  It seems to me, that the smaller the sensor, the more DOF an image of that subject is going to have.  Because both sensor and subject are tiny.

Rather sad that you're still clinging to the same flawed understanding of what determines depth of field.

"To make a mistake is only an error in judgment, but to adhere to it when it is discovered shows infirmity of character."  —Dale Turner
Title: Re: Crop sensors better than full frame for macro photography?
Post by: CarlTN on February 26, 2014, 11:21:41 PM
My post was deleted but I sent it to you privately, neuro.

I can see this argument must now end, because well...anything else I say is going to get deleted anyway.

Yes, I can see why it was deleted.

"Insults are the arguments employed by those who are in the wrong."  —Jean-Jacques Rousseau


But in the "macro" world, you're taking a picture of something that is tiny.  It seems to me, that the smaller the sensor, the more DOF an image of that subject is going to have.  Because both sensor and subject are tiny.

Rather sad that you're still clinging to the same flawed understanding of what determines depth of field.

"To make a mistake is only an error in judgment, but to adhere to it when it is discovered shows infirmity of character."  —Dale Turner

That's because I am sad, a sad little man wearing pink tights, I can't be manly like you...not on here...you're the big man on campus  ::)
Title: Re: Crop sensors better than full frame for macro photography?
Post by: pdirestajr on February 26, 2014, 11:39:22 PM
Hi I've photographed products with a 7D while my 5D2 watched in disgust. I then charged the client money for this craziness. They had no idea. I sure fooled them!
Title: Re: Crop sensors better than full frame for macro photography?
Post by: CarlTN on February 27, 2014, 03:22:48 AM
Hi I've photographed products with a 7D while my 5D2 watched in disgust. I then charged the client money for this craziness. They had no idea. I sure fooled them!

If you have a 5D2 that is self aware, then perhaps it is a better and smarter camera than I have thought it was all this time!  My 6D can't quite attain self awareness.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: philmoz on February 27, 2014, 04:52:30 AM
I agree, for macro photography, a crop sensor has the edge.  Unless of course, you're a fan of focus stacking 10 or more images...which I'm not.  A full frame sensor necessarily requires more focus stacking, unless you want your macro images with shallow depth of field...in which case either FF or crop are ok for that.  I don't profess to be a macro expert, though...but I do know that a macro image I shot with an effective 270mm focal length at f/20 on a crop camera, would have needed to be at f/45 or smaller on a full frame sensor, and would have provided 1.6x less magnification to boot.

I'm not a macro expert here; but I think you're mistaken here.

I may be interpreting things incorrectly, or have the math wrong - apologies in advance if this is the case :)

My understanding is that for macro photography the DoF calculation is different and the lens focal length does not play a factor - only the aperture, sensor circle of confusion and image magnification are important.
See http://en.wikipedia.org/wiki/Depth_of_field (http://en.wikipedia.org/wiki/Depth_of_field) (Close Up section).

By image magnification I mean the size of the object being photographed on the sensor compared to it's size in real life. So for 1:1 magnification a 1cm square object will occupy 1cm square on the sensor regardless of the camera sensor size.

The circle of confusion on the FF camera is 0.029mm and on the APS-C camera it is 0.018mm.
http://en.wikipedia.org/wiki/Circle_of_confusion (http://en.wikipedia.org/wiki/Circle_of_confusion)

If magnification and aperture are the same then the FF sensor has a DoF that is 1.6 times larger than the APS-C camera (0.029 / 0.018).

Obviously the two cameras are capturing different images. At 1:1 magnification the FF camera is capturing a 36mm x 24mm area of the subject, while the APS-C only captures a 14.8mm x 22.2mm area of the subject.

You could get similar DoF on the APS-C camera by decreasing aperture by 1 1/3 stops, which would require a corresponding increase of ISO or shutter speed to compensate the exposure.

I would guess that most macro photographers want to maximise the size of their subject on the sensor to get the best image possible :)

In order to capture the same subject size relative to the sensor size we need to change the magnification for one of the cameras. For example if the subject fills the APS-C frame at 1:1 then we need to shoot at 1.6:1 on the FF camera in order to expand the subject to fill the frame. Conversely if the subject fills the FF sensor we need to reduce magnification to 1:1.6 on the APS-C camera in order to capture the whole subject without cutting off any parts.

Increasing the magnification on the FF camera to 1.6:1 will roughly halve its DoF.
Decreasing the magnification on the APS-C camera to 1:1.6 will roughly double its DoF.
In both cases the APS-C camera will now have more DoF than the FF camera by a factor of approximately 1.25.

Of course we can now decrease the aperture on the FF camera by 1 stop and it will again have slightly greater DoF than the APS-C camera.

In summary:
- At the same magnification the FF camera has 1.6 times more DoF than the APS-C camera
- If the subject fills the same percentage of the sensor then the APS-C has the DoF advantage by a factor of 1.25. A 1 stop decrease in aperture gives the advantage back to the FF camera.

Phil.


Title: Re: Crop sensors better than full frame for macro photography?
Post by: Northstar on February 27, 2014, 04:53:26 AM
Hopefully this is helpful for some folks following this discussion.

When using the exact same:

1. Focal length
2. Aperture
3. Distance to target

The following two images show what happens to the depth of field when using a crop vs a FF camera.  I've compared a 5d3 with a 7D.  Note that the crop camera has a shallower depth of field

For anyone following this post that wants to learn more about depth of field and how it changes with different apertures, distances, and focal lengths, then go play around with the following website.  (Neuro referenced it earlier)

http://www.dofmaster.com/dofjs.html (http://www.dofmaster.com/dofjs.html)

Title: Re: Crop sensors better than full frame for macro photography?
Post by: SambalOelek on February 27, 2014, 05:17:25 AM
I have spent quite some time trying to find the best camera for macrophotography (handheld, >1:1 magnification). This is similar to being reach limited in conventional photography.

The 60D is a joy to use for this kind of photography, because of the articulated screen and the built-in Speedlite transmitter. On the other hand, using a large, clear (read: full frame) viewfinder makes the camera more stable.

I personally found that the "reach"/pixels on target advantage of APS-C didn't result in better overall image quality, because of the noise creeping in at low/moderate ISOs. But it does come close at ISO 400 or lower. In my opinion, the 60D/7D outperform the 5D Mark II, but not the Mark III.

The 1D Mark IV with its medium-density APS-H sensor performs really well, but loses out to the 5D Mark III at higher ISOs. The aging 1Ds Mark III is a joy to use, with its fantastic viewfinder, but noise starts to creep in really quickly, and the LCD is useless to determine sharpness at the pixel level.

Overall, the 1D X and 6D deliver the best quality, with the weak spot of the 6D being its viewfinder. Obviously, Wi-Fi is not that useful for handheld macro.

Best image quality:
Title: Re: Crop sensors better than full frame for macro photography?
Post by: Marsu42 on February 27, 2014, 05:18:06 AM
When using the exact same:
1. Focal length
2. Aperture
3. Distance to target

Thanks, but I suspect most of us know about that, but just to recapitulate and not enter any mudslinging again :-p the issue at hand is:

* same focal lengths just for the sake of discussion, but the different working distance for live critters is an issue

* not the same distance to target to have the same framing (I'd like the butterfly to fill my frame, no matter the sensor size). Given the specifics of a macro lens, this might also mean the effective f-stop differs even more than at standard distances.

* not the same aperture to reach a comparable dof, resulting in an iso shift

Overall, the 1D X and 6D deliver the best quality, with the weak spot of the 6D being its viewfinder

Um, what's wrong with the 6d vf? I've never come near a 1dx, so I cannot tell the difference and what you might refer to.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: Northstar on February 27, 2014, 05:49:35 AM
When using the exact same:
1. Focal length
2. Aperture
3. Distance to target

Thanks, but I suspect most of us know about that, but just to recapitulate and not enter any mudslinging again :-p the issue at hand is:

* same focal lengths just for the sake of discussion, but the different working distance for live critters is an issue

* not the same distance to target to have the same framing (I'd like the butterfly to fill my frame, no matter the sensor size). Given the specifics of a macro lens, this might also mean the effective f-stop differs even more than at standard distances.

* not the same aperture to reach a comparable dof, resulting in an iso shift

Overall, the 1D X and 6D deliver the best quality, with the weak spot of the 6D being its viewfinder

Um, what's wrong with the 6d vf? I've never come near a 1dx, so I cannot tell the difference and what you might refer to.

Marsu...I think you're right that many know about it, but I also think many don't and/or don't know it well enough.  It's an incredible learning tool/website for those that don't, or want to learn more....which is why I posted.

It's much easier to learn about DOF when you manipulate the variables on a calculator and see actual results versus reading about the subject.   And for macro work, DOF knowledge is critical.

As to the OP's original question, I think with good light it doesn't matter so much, but if you have golden hour light and need to work with higher ISO values then I would much rather have the FF.   
Title: Re: Crop sensors better than full frame for macro photography?
Post by: Marsu42 on February 27, 2014, 05:55:30 AM
Marsu...I think you're right that many know about it, but I also think many don't and/or don't know it well enough.  It's an incredible learning tool/website for those that don't, or want to learn more....which is why I posted.

I didn't want to criticize, on the contrary, posting standard links now and again is a good idea since old threads obviously seldom get read :-p ... speaking of which and concerning 1dx/6d/60 & ff/crop, I didn't post this link for some weeks now :->

Pro DSLR + Cheapo Lens vs "Cheapo" DSLR + Pro Lens (http://www.youtube.com/watch?v=hk5IMmEDWH4#ws)
Title: Re: Crop sensors better than full frame for macro photography?
Post by: SambalOelek on February 27, 2014, 06:15:12 AM
Overall, the 1D X
and 6D deliver the best quality, with the weak spot of the 6D being its viewfinder

Um, what's wrong with the 6d vf? I've never come near a 1dx, so I cannot tell the difference and what you might refer to.

There is nothing inherently wrong with the 6D viewfinder, but the 1D X has a significantly larger image. The specs are 0.76x vs. 0x71x magnification, and ~97% vs. ~100% coverage, respectively. I think those numbers do not really tell the whole story, it is really a big difference. When trying to manually focus at macro distances, you want as good a viewfinder as possible.

On the other hand, someone coming from a xxxD would be blown away by the large, bright viewfinder of the 6D. It is a pity that Canon does not put 100% viewfinders in their entry-level cameras, as the optical viewfinder should be one of the main selling points of DSLRs these days. Even the cheapest Pentax DSLR has a viewfinder comparable to the 7D. But I digress..

Title: Re: Crop sensors better than full frame for macro photography?
Post by: Northstar on February 27, 2014, 06:44:33 AM
Marsu...I think you're right that many know about it, but I also think many don't and/or don't know it well enough.  It's an incredible learning tool/website for those that don't, or want to learn more....which is why I posted.

I didn't want to criticize, on the contrary, posting standard links now and again is a good idea since old threads obviously seldom get read :-p ... speaking of which and concerning 1dx/6d/60 & ff/crop, I didn't post this link for some weeks now :->

Pro DSLR + Cheapo Lens vs "Cheapo" DSLR + Pro Lens (http://www.youtube.com/watch?v=hk5IMmEDWH4#ws)

No offense taken.

I've seen that video, I think Kai does some funny stuff from time to time...rather hit or miss though.   I just noticed he posted a new video on how to shoot nude portraits that I'm sure some would enjoy....for learning purposes of course.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: Marsu42 on February 27, 2014, 06:47:22 AM
It is a pity that Canon does not put 100% viewfinders in their entry-level cameras, as the optical viewfinder should be one of the main selling points of DSLRs these days.

Even if I'll get flamed down (again) I'd like to mention I don't even want a 100% vf ... as I don't do stock photography where I'd need to sell the whole raw image, a bit of a safety margin is nice to have. I do agree about the magnification though, my good ol' film eos 620 has a *much* better vf than the modern and expensive 6d :-(

I've seen that video, I think Kai does some funny stuff from time to time...rather hit or miss though.

Actually this is the only video I like because he's very authentic as Mr. Ape with a "real man's camera" ... but I don't think his reviews are very useful, and certainly not his random camera/lens destruction. To me, he just seems to be a guy with too much time and money on his hands.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: dak723 on February 27, 2014, 07:59:53 AM
Though perhaps not strictly considered macro photography, I do a lot of photography of flowers.  For many years I owned a crop camera (Original Rebel) and took many photos of flowers at distances of 2 to 3 feet on average.  Since flowers aren't flat, having enough DOF to get a good percentage of the flower in focus is important - perhaps a DOF of an inch or so.  This meant shooting at around f/11 with my Canon 100mm Macro (non-L) lens.  Going to full frame and wanting to frame my photos the same, it becomes almost impossible to get the photo with a similar DOF.  Again, this is trying to frame the photo the same - not crop - thus moving the camera closer to get the same shot and an adequate DOF.  With the FF camera and the same lens, I now need to shoot at about f/20 to get the same DOF.  Needless to say, if I need more than an inch of DOF, the lens apertures don't go high enough when using the FF camera.  So, I don't know which is better - crop or FF sensor, but in my case, the crop camera did the better job.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: Marsu42 on February 27, 2014, 08:39:20 AM
So, I don't know which is better - crop or FF sensor, but in my case, the crop camera did the better job.

But, but, but it cannot be - ff is better, it has to be because it's more expensive this a is known truth :-> ...

... ok, jokes aside, you should do focus stacking in these situations - either via a tethered laptop or via Magic Lantern, this is exactly what it's made for. Closing the aperture too much kills the sharpness, and at the same time you don't get a nice/blurry background anymore.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: neuroanatomist on February 27, 2014, 09:05:31 AM
Though perhaps not strictly considered macro photography, I do a lot of photography of flowers.  For many years I owned a crop camera (Original Rebel) and took many photos of flowers at distances of 2 to 3 feet on average.  Since flowers aren't flat, having enough DOF to get a good percentage of the flower in focus is important - perhaps a DOF of an inch or so.  This meant shooting at around f/11 with my Canon 100mm Macro (non-L) lens.  Going to full frame and wanting to frame my photos the same, it becomes almost impossible to get the photo with a similar DOF.  Again, this is trying to frame the photo the same - not crop - thus moving the camera closer to get the same shot and an adequate DOF.  With the FF camera and the same lens, I now need to shoot at about f/20 to get the same DOF.  Needless to say, if I need more than an inch of DOF, the lens apertures don't go high enough when using the FF camera.  So, I don't know which is better - crop or FF sensor, but in my case, the crop camera did the better job.

What do you find almost impossible?  Moving the full frame camera closer to the flower to match the framing?  Stopping the lens on the full frame camera down to match the DoF?  Raising the ISO on the full frame camera to compensate for the light lost by stopping down?  The concept of equivalence means that after doing all of those things, you are getting the same picture in terms of framing, DoF, and noise.  That's with sensors of the same generation, if you're comparing the image quality of a reasonably recent full frame camera to your old Digital Rebel, the IQ of the full frame will be significantly better. 

The only time it's 'impossible' is if you're at such a narrow aperture on APS-C that stopping the lens down the extra 1.33-stops would exceed the minimum aperture of the lens (and in that case, as Marsu42 points out you're losing a lot of sharpness to diffraction and would be better off focus stacking with a static subject like a flower).
Title: Re: Crop sensors better than full frame for macro photography?
Post by: neuroanatomist on February 27, 2014, 09:30:31 AM
But, but, but it cannot be - ff is better, it has to be because it's more expensive this a is known truth :-> ...

LOL. 

I know you're joking, but in truth, in almost all situations from macro to wide angle to telephoto, a FF sensor will give you results that are either the same as or better than an APS-C sensor (the same when all factors are equalized to give the same picture, better if you don't need to match every aspect of the picture, and better if you need to use higher ISO settings…but worse if you need the full resolution of the smaller sensor for your required output).  If smaller sensors were really better, then m4/3 would be better than APS-C, and the absolute best choice for everyone who shoots macro would be the Pentax Q with it's 5.6x crop factor.

Note that 'sensor' is an important point - when you compare cameras, other factors come into play - although not too important for macro, the better AF of the 7D vs. the 5DII is a notable example with which I have personal experience.  System cost, as well as things like swivel screens, availability of Magic Lantern for particular bodies (trap focus would be enormously helpful for handheld shooting with the MP-E 65!), etc., are all factors to consider.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: Marsu42 on February 27, 2014, 10:14:59 AM
in almost all situations from macro to wide angle to telephoto, a FF sensor will give you results that are either the same as or better than an APS-C sensor

... It's good you're pointing out you're talking only about the sensor, not about camera bodies which might have features like a swivel screen, and not about other aspects like working distance.

So concentrating on the sensor, and assuming for the sake of argument that ff is "better" the question is: How noticeable is this difference, i.e. what export size, what audience, and is it worth the immense price difference for the camera and lenses? And until proven wrong I'd continue to insist that with macro photography, this difference rather small, if any.

But after going around in circles I admit at this point I'd really like to see some "same framing, same dof" examples of 20mp 6d vs 20mp 70d with 100L for different lens-object distances. I have my personal experience with butterflies and fireflies, but of course I cannot generalize that.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: neuroanatomist on February 27, 2014, 10:37:36 AM
So concentrating on the sensor, and assuming for the sake of argument that ff is "better" the question is: How noticeable is this difference, i.e. what export size, what audience, and is it worth the immense price difference for the camera and lenses? And until proven wrong I'd continue to insist that with macro photography, this difference rather small, if any.

Frankly, in many situations the differences are relatively minor (and as stated, for truly equivalent shots at relatively low ISO, the FF has no advantage at all - they are equivalent).  What FF gives you is the ability to choose a thinner DoF if you want it, use a faster shutter speed if DoF isn't a limitation, have lower noise and greater post-processing flexibility, etc.  The benefits of FF are most evident when pushing the envelope, so to speak. 

Whether it's 'worth the immense price difference for the camera and lenses' is a decision everyone must make for themselves, based on need, want and/or budget.  Is a Ferrari worth the immense price difference over the Subaru that I drive?  Presumably yes, to the people driving them in stop-and-go traffic next to me on the highway commuting to and from work – but to me, no.  Plus in certain, specific cases – such as driving on the highway when snow is falling at >2" per hour and the road crews can't keep up – I'd say my all-wheel drive Subaru is better than a Ferrari…at least, it was better than the Ferrari I saw spun off into the ditch on the side of the Mass Pike, that I drove past on my way home in a snowstorm a couple of weeks ago.   ;)
Title: Re: Crop sensors better than full frame for macro photography?
Post by: mackguyver on February 27, 2014, 10:41:20 AM
in almost all situations from macro to wide angle to telephoto, a FF sensor will give you results that are either the same as or better than an APS-C sensor

... It's good you're pointing out you're talking only about the sensor, not about camera bodies which might have features like a swivel screen, and not about other aspects like working distance.
Marsu, that is a good point - the swivel screen on my 60D rocked for macro and I miss it.  I still think the FF ergonomic trade-offs are worth it for better IQ, but I spend more time on the ground than I did with my 60D.  I often print at large sizes 20"x30" and up so the differences are noticeable, but for the majority of people that isn't a concern.

I will leave this post alone from now on, but in my opinion as someone who shots a lot of macro, all this DOF debate stuff is just a bunch of crap.  Macro is hard, period, and a good macro lens and excellent technique are what matter most.  The silliness I've seen in this thread won't make anyone a better macro photographer.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: Marsu42 on February 27, 2014, 10:46:39 AM
What FF gives you is the ability to choose a thinner DoF if you want it, use a faster shutter speed if DoF isn't a limitation, have lower noise and greater post-processing flexibility, etc.  The benefits of FF are most evident when pushing the envelope, so to speak.

I know, that's why I put €1500 into a 6d though my 60d is still running fine. I was just surprised how little the (subjective) iq advantage is for macro and how much the loss of swivel screen & working distance hurts. The ff certainly gives you a different "look" for natural macro subjects, but that's more of a artistic advantage rather than something I could attribute to sharpness or noise.

The one thing I do continue to mention is the postprocessing flexibility you also mentioned, but if properly exposing & focus-stacking a mushroom I didn't find that to be really necessary. What I often really *would* need is simply more dr for highlights, but we talked about that :-p and some fixes are available with bracketing or Magic Lantern dual_iso.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: BL on February 27, 2014, 12:09:04 PM
I choose the M over FF most of the time for macro because of working distance.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: dtaylor on February 27, 2014, 05:02:32 PM
I choose the M over FF most of the time for macro because of working distance.

Bingo. You can get the shot either way, but the smaller sensor will give you a little more room to work.

6 pages of people arguing tiny differences that make little or no difference in the real world or your final images. Sensors are so good now that there are only two categories where format seems to matter at all:

* Really low light stuff like astrophotography and astro-landscapes. FF tends to dominate here though you still see good work from APS-C.

* Wall sized landscape prints with incredible detail and zero noise/artifacts. You have to see these in a gallery to appreciate them, and they are all scanned and digitally processed LF film, or MF digital.

For everything else it matters little whether it's FF, APS-C, or 4/3. For some reason we love to pretend otherwise.

Looking over the best macros at a photo sharing site like Flickr, the key to top rated macro work is not format, but mastering focus stacking and lighting. Which camera do you choose? Whichever one appeals to your budget and desired features.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: eml58 on February 27, 2014, 06:58:10 PM
I was hesitant to make a comment here, but things seem to have calmed down a little.

I do a lot of Macro, albeit it's all Underwater Imaging, I have two set ups for Underwater.

1DMK IV in a Seacam Housing, I find the APS-H format just get's me closer and for my Macro Imaging works better than anything else I've tried (FF/APS-C), primarily it allows me to better utilise the 100f/2.8 Macro L IS.

For everything else I use the 5DMK III again in a Seacam Housing, FF seems to the wide angle Imaging better than the 1.3 Crop of the APS-H format.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: ecka on February 28, 2014, 03:14:40 AM
When I was using 7D for macro (mostly hand held) it was very difficult to get the right framing and the subject in perfect focus at the same time. Now, with 6D I don't worry about the framing so much (or at all), because FF is much more crop-friendly, so I can focus on timing and DoF positioning.
Another FF advantage is MP-E 65/2.8 1-5x Macro, which is somewhat limited by it's lowest magnification of 1:1 macro and not every insect is small enough to fit inside APSC framing without cropping something off (long legs, whiskers, etc). You can always crop, so FF gives more flexibility.
TBH, when talking about size, I think that crop sensor has no advantages other than price.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: neuroanatomist on February 28, 2014, 06:28:46 AM
TBH, when talking about size, I think that crop sensor has no advantages other than price.

Agreed.  Not that you can't make excellent images with a crop sensor, but lower cost is its real advantage.
Title: Re: Crop sensors better than full frame for macro photography?
Post by: Jeevz on March 02, 2014, 04:32:58 AM
I was hesitant to make a comment here, but things seem to have calmed down a little.

I do a lot of Macro, albeit it's all Underwater Imaging, I have two set ups for Underwater.

1DMK IV in a Seacam Housing, I find the APS-H format just get's me closer and for my Macro Imaging works better than anything else I've tried (FF/APS-C), primarily it allows me to better utilise the 100f/2.8 Macro L IS.

For everything else I use the 5DMK III again in a Seacam Housing, FF seems to the wide angle Imaging better than the 1.3 Crop of the APS-H format.

For me - shooting underwater macro - I am very happy with my 7d + 100L - (granted the 1d series + housing is a little out of my price range)

The reason I like aps-c is because of the greater working distance (not always necessary) but there are some shots I am sure I couldn't get on full frame underwater (and there is no port for the 180L on my ikelite setup).

I do plan to put together a FF rig sometime soon, but I will keep my 7d mainly for underwater macro.

Just my opinion in regards to my shooting.