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Gear Talk => EOS Bodies - For Stills => Topic started by: Cory on November 06, 2013, 09:46:40 PM

Title: Major IQ advantage of FF?
Post by: Cory on November 06, 2013, 09:46:40 PM
I know that you get a more shallow DOF and better high ISO performance with a full frame over a crop, but with good lenses on either is there really much of an IQ difference all other things being equal.  I do get great results with my T1i, but I do see some ultra-great results out there that my camera just isn't capable of.  The sensible option is to remain with my crop-inspired lenses and maybe go to a 70D or the next Rebel, but the 6D seems pretty cool. 
I agonize over this stuff because I'm the opposite of a gear-hound.  I'm a minimalist who tries to do the most with the least so it's quality over quantity.  Thank you in advance for your wisdom.
Title: Re: Major IQ advantage of FF?
Post by: BozillaNZ on November 06, 2013, 10:07:11 PM
Not a gear hound? Then don't even ask this question, stick to what you have and be happy! APS-C more than good enough.
Title: Re: Major IQ advantage of FF?
Post by: Don Haines on November 06, 2013, 10:11:50 PM
That's not an easy question to answer....

There are a few good rules of thumb to consider....

1) Nobody cares about the IQ of an out of focus picture (get a good AF system for YOUR needs)
2) FF works better in poor light...
3) FF gives less distortion with wide angles while crop gives more pixels on target for distant objects.
4) FF is more forgiving of lens limitations than crop. (Kit lenses on a crop camera give poor sharpness, but a quality lens is good on FF and crop)
5) Crop is lighter and less expensive.
6) Most important.... good image editing software!!!!!!

So much depends on how and what you shoot... If you are shooting indoors and with wide angles FF is hard to beat.... If you are trying to track fast moving objects, AF is the most important thing to have. If you are shooting distant wildlife, and can not afford a $10,000 super-telephoto, crop is great... We all have a different set of requirements so everyone's answer will be different. Whichever route you take, there is one constant, decent image editing software will have the most "bang for the buck".
Title: Re: Major IQ advantage of FF?
Post by: Mt Spokane Photography on November 06, 2013, 10:15:20 PM
I was amazed at the amount of detail when I went from a 30D to a 5D several years back.  The 30D was a good camera of the day.
 
That said, at ISO 100 you will not see a huge difference in IQ.  But for difficult lighting, a FF pulls away.
 
You generally do not need as good of a lens on FF as you do on a crop due to the larger photosites.  Pretty much any lens will have more resolution in the center on a FF body, but usually the edges won't be quite as good.
 
I use crop and FF both, I'm not worried about the IQ of either, but in difficult lighting, I always use the FF body.
Title: Re: Major IQ advantage of FF?
Post by: paul13walnut5 on November 06, 2013, 10:21:01 PM
Can you link to an image that your 500D isn't capable of, but 135/leica/minature format DSLR is before I comment.

If its brids in flight, ok.

It its a sprinter running straight at you.  Ok.

If it's astrophotography.  Ok.

For everything else, 500D should be a good companion.  But if you have the full frame termites in your brain, maybe better to make sure that any new lenses you buy are EF.
Title: Re: Major IQ advantage of FF?
Post by: Don Haines on November 06, 2013, 10:35:04 PM
About software having more of an effect than bodies or lenses.... Same picture, taken with a crop camera and a 12mm lens.... This picture has overexposed areas and dark areas, because of the wide angle lens used, note the distortion.... the fellow in the bottom right is walking at quite an angle.


Using lightroom, adjust the white balance (#1 reason to shoot in RAW), drop down the brightness of the overexposed area and bring up the detail in the shadows. Enable the lens profile and the vignetting and some of the distortion goes away, then tweak the manual adjustments for distortion and our friend can now walk upright again :)

Seriously, software like lightroom and shooting in RAW will have more of an impact on your pictures than a $3000 camera and $5000 of lenses...
Title: Re: Major IQ advantage of FF?
Post by: docholliday on November 06, 2013, 11:34:12 PM
There's a huge difference between being a gearhead and having the right tools for the situation. There's a difference with spending the right money in the right places for the right items vs being cheap. And, there's a difference with trying to "improvise" with less than optimal gear and learning to use the right gear correctly.

Learning to control light, use PP tools well, and the stopping at/overcoming/removing the limitations of the tools at hand will do more than upgrading any body or lens. Well, that is until you find the limitation to be that piece of gear...
Title: Re: Major IQ advantage of FF?
Post by: duydaniel on November 07, 2013, 12:02:17 AM
I went from Nikon D5100 to Canon 5D3
and I saw about 10% improvement in IQ over all.

Stick with DX
Title: Re: Major IQ advantage of FF?
Post by: TexPhoto on November 07, 2013, 12:21:23 AM
In many things the more you get into something the more you understand and perceive the complexities.  I am not a wine guy and $100 a bottle wine does not taste much different to me than $10.  So while I'm not going to buy $100 bottles of wine, I'm not going to sit and debate the guy who does.

FF has some advantages as does crop.  If you can afford it and enjoy it, buy what suits you, heck buy both.

The wonderful thing about photography is while many debate FF/crop, RAW vs. Jpeg, and on and on, others will produce, display and sell quality images.
Title: Re: Major IQ advantage of FF?
Post by: Woody on November 07, 2013, 12:40:10 AM
Image details. Use the ISO 12233 Sample Crops in The Digital Pictures to see the difference.
Title: Re: Major IQ advantage of FF?
Post by: Woody on November 07, 2013, 12:47:44 AM
In many things the more you get into something the more you understand and perceive the complexities.  I am not a wine guy and $100 a bottle wine does not taste much different to me than $10.  So while I'm not going to buy $100 bottles of wine, I'm not going to sit and debate the guy who does.

FF has some advantages as does crop.  If you can afford it and enjoy it, buy what suits you, heck buy both.

The wonderful thing about photography is while many debate FF/crop, RAW vs. Jpeg, and on and on, others will produce, display and sell quality images.

Well said!
Title: Re: Major IQ advantage of FF?
Post by: David_in_Seattle on November 07, 2013, 12:48:18 AM
I know that you get a more shallow DOF and better high ISO performance with a full frame over a crop, but with good lenses on either is there really much of an IQ difference all other things being equal.  I do get great results with my T1i, but I do see some ultra-great results out there that my camera just isn't capable of.  The sensible option is to remain with my crop-inspired lenses and maybe go to a 70D or the next Rebel, but the 6D seems pretty cool. 
I agonize over this stuff because I'm the opposite of a gear-hound.  I'm a minimalist who tries to do the most with the least so it's quality over quantity.  Thank you in advance for your wisdom.

The points you stated are very good reasons for why someone would transition from crop to full frame cameras.  I'd add the notion that if you buy a really nice lens, like the 50mm f1.2, then what's the point of using it on a crop sensor camera when you will not be able to utilize the key feature of this lens (super shallow DOF)?  On a crop sensor camera f1.2 is close to the visual DOF equivalent of f1.8 on a full frame.  In addition, the lens now becomes 80mm due to the crop so you'll never be able to utilize the true focal perspective in combination to its DOF. 

Another thing I'll mention is that I notice much more contrast and saturation on my 5Dmk3 vs 60D when using the same lens.  I figured the sensor and processor on the 5Dmk3 is able to capture more color detail even though both cameras capture 14bit RAW images.

I still keep my 60D with the 17-55 lens (and will upgrade to the 70D) because it's much lighter than my 5Dmk3 and still takes great photos and records excellent video.
Title: Re: Major IQ advantage of FF?
Post by: gmrza on November 07, 2013, 01:19:51 AM
I know that you get a more shallow DOF and better high ISO performance with a full frame over a crop, but with good lenses on either is there really much of an IQ difference all other things being equal.  I do get great results with my T1i, but I do see some ultra-great results out there that my camera just isn't capable of.  The sensible option is to remain with my crop-inspired lenses and maybe go to a 70D or the next Rebel, but the 6D seems pretty cool. 
I agonize over this stuff because I'm the opposite of a gear-hound.  I'm a minimalist who tries to do the most with the least so it's quality over quantity.  Thank you in advance for your wisdom.

This is not a scientific analysis, because the two frames below were shot under different conditions, but it gives some illustration.  The first frame was taken with a 5D3 using a 24-70 f/2.8II and the second with a 7D using the 50mm f/1.4.  Both are good lenses, but the 24-70 is stellar - it is visibly better, so take sharpness and contrast between the images with a bit of a grain of salt.

The lighting between the shots is different - the image with the 5D3 was shot with flash at ISO1250, while the shot taken with the 7D is using ambient light at ISO 100.  Still, look at the shadow detail, it is very different.

Most importantly - take this comparison for what it is - I just pulled 100% crops from 2 existing images, shot with different lighting, using different lenses, at different ISOs - this is not a well-controlled experiment.
Title: Re: Major IQ advantage of FF?
Post by: pulseimages on November 07, 2013, 01:28:16 AM
I know that you get a more shallow DOF and better high ISO performance with a full frame over a crop, but with good lenses on either is there really much of an IQ difference all other things being equal.  I do get great results with my T1i, but I do see some ultra-great results out there that my camera just isn't capable of.  The sensible option is to remain with my crop-inspired lenses and maybe go to a 70D or the next Rebel, but the 6D seems pretty cool. 
I agonize over this stuff because I'm the opposite of a gear-hound.  I'm a minimalist who tries to do the most with the least so it's quality over quantity.  Thank you in advance for your wisdom.

This is not a scientific analysis, because the two frames below were shot under different conditions, but it gives some illustration.  The first frame was taken with a 5D3 using a 24-70 f/2.8II and the second with a 7D using the 50mm f/1.4.  Both are good lenses, but the 24-70 is stellar - it is visibly better, so take sharpness and contrast between the images with a bit of a grain of salt.

The lighting between the shots is different - the image with the 5D3 was shot with flash at ISO1250, while the shot taken with the 7D is using ambient light at ISO 100.  Still, look at the shadow detail, it is very different.

Most importantly - take this comparison for what it is - I just pulled 100% crops from 2 existing images, shot with different lighting, using different lenses, at different ISOs - this is not a well-controlled experiment.

Good examples! While they are somewhat close the 5D3 image has way more pop. :)
Title: Re: Major IQ advantage of FF?
Post by: wayno on November 07, 2013, 01:29:58 AM
When I moved to FF I noticed the shallow DOF thing immediately. But also, I found my F8 landscapes etc had a subtly more cinematic and dimensional quality. It might be a perception/subjective thing but for me, it was noticable. There is something lush about FF at any aperture that ordinarily is not the case with crop. That could well be blamed on lens differences but I think it's more profound. Just my personal take.
Title: Re: Major IQ advantage of FF?
Post by: sanj on November 07, 2013, 01:40:33 AM
Of course full frame is better.

Why would you not shoot full frame? If you do not go overboard and limit yourself to say a 6D and a decent lens what would be the cost difference between this and crop? Not enough to matter in the long run.
Title: Re: Major IQ advantage of FF?
Post by: gmrza on November 07, 2013, 01:49:49 AM

Good examples! While they are somewhat close the 5D3 image has way more pop. :)

Therein lies part of the problem of my comparison - a good part of that "pop" is due to the 24-70 f/2.8II.  Pay more attention to shadow detail and noise, which is less due to the lens.

The 24-70 f/2.8 II is much better in this respect than the 50mm f/1.4 in terms of contrast and colour rendition.
Title: Re: Major IQ advantage of FF?
Post by: Nishi Drew on November 07, 2013, 03:45:08 AM
Of course full frame is better.

Why would you not shoot full frame? If you do not go overboard and limit yourself to say a 6D and a decent lens what would be the cost difference between this and crop? Not enough to matter in the long run.

However, better lenses are required, though shooting F/2 on APS-C is close to shooting F/2.8 on FF, which means the stopped down performance advantage with equal DOF is there with FF, but lenses tend to perform better on APS-C in regards to taking the good center IQ of a lens. I've compared shots with my 5DII + Sigma 35mm and a friend's X100, the images come so close to performance with image quality and ISO performance, my lens was sharper wide open and of course, I could go twice as shallow, but the colors and overall picture the X100 can put out with plain Jpegs are just marvelous, this made me reconsider the relevance of full frame for a while...
But, I'm comparing an FF from 2008 and a crop from 2010, so, smaller sensor cameras will outperform older larger sensor cameras, but in terms of latest tech the bigger sensor will outperform the smaller in ISO performance, color depth, DR etc. but it's all an eventual catch up game I believe
Title: Re: Major IQ advantage of FF?
Post by: Marsu42 on November 07, 2013, 05:38:51 AM
I know that you get a more shallow DOF and better high ISO performance with a full frame over a crop, but with good lenses on either is there really much of an IQ difference all other things being equal.

I recently added a 6d to my 60d, so I would say that next to intensive research I know both sides pretty well by now, so here's my general take: It is true that it is very hard to tell a unprocessed shot from a crop at low iso from a ff (at the same dof of course), and iso noise doesn't matter if you are shooting for key chain holder print size. *But* there are hidden aspects:

* ff has more leverage for postprocessing, this is what matters the most to me. If you try to raise one color channel on a gradient (say lessen or intensify blue on a partly cloudy sky) the crop shot will immediately fall apart while the bigger ff pixels allow for more postprocessing creativity or fixing. Also the ff has less problems on the red color channel on plain surfaces, a known issue with Canon sensors, try shooting a red mushroom if you don't know what I'm talking about.

* The recent ff models like 6d have virtually no banding (well, I've never seen it), quite unlike the 60d, not to speak of the older 7d - I don't know if this has gotten any better with the 70d. Banding after raising shadows is what kills your shot while you can reduce the film-like iso noise on the recent ff models a lot esp. with newer algorithms like DxO PRIME. In reality, I find the ff has a 2-3 stop advantage over crop because with crop iso800 is the highest "safe" setting while with the 6d it's iso6400, and truth to be told I'd still prefer the latter if the dr is low.

* Crop is equal to ff with good lenses, but you really have look out for them or use ef-s - my midrange 17-40L and 70-300L are much sharper wide open on ff, though the tele zoom has a radial bokeh on the outside that you can like (or not) that is cut away by crop.

* Noise: I'd like to advise not to underestimate the freedom this gives you, it's not just for very large prints nobody will really do but with crop you constantly have to trade shutter speed vs. iso noise as crop @iso800 is already problematic. Unless the dr is very high with ff you can just use a higher shutter which results in much more keepers, less headaches about tech but more thought about composition.

* If you use Magic Lantern: with ff you can boost your dynamic range to 14ev with a dual_iso 100/800 shot with virtually no drawback because noise doesn't matter at these settings - with crop iso800 already has noise so it's getting awkward. Also to get a thinner dof with crop you have to carry much more bulk, with ff my compact 70-300L @f4 is "thin enough" for me.

* Viewfinder: Not directly sensor-iq related and last, but not least - the more expensive crop cameras have an somewhat ok vf, but with ff you see more of what you're shooting due to the larger mirror which is a reason for ff on its own as in "iq for your eye".

I keep using my 60d because it's better for macro (deeper dof, larger working range) and tripod (swivel screen) as the 100L and 17-40L (@f8+) is sharp enough for crop - and of course for tele shots with 300mm * 1.6x crop factor which makes a decisive difference for wildlife. So I ended up where Canon wants you to end up - buying two cameras :-p
Title: Re: Major IQ advantage of FF?
Post by: dtaylor on November 07, 2013, 06:16:43 AM
3) FF gives less distortion with wide angles while crop gives more pixels on target for distant objects.

First part is false. Distortion is the same for the FoV (assuming equal lens IQ).

Quote
4) FF is more forgiving of lens limitations than crop. (Kit lenses on a crop camera give poor sharpness, but a quality lens is good on FF and crop)

FF is more forgiving of lens sharpness, but less forgiving of side and corner performance.
Title: Re: Major IQ advantage of FF?
Post by: dtaylor on November 07, 2013, 06:24:51 AM
* ff has more leverage for postprocessing, this is what matters the most to me. If you try to raise one color channel on a gradient (say lessen or intensify blue on a partly cloudy sky) the crop shot will immediately fall apart while the bigger ff pixels allow for more postprocessing creativity or fixing.

This is true but an exaggeration. Crop images do not 'immediately fall apart.' You have to push to see the difference.

Quote
Also the ff has less problems on the red color channel on plain surfaces, a known issue with Canon sensors, try shooting a red mushroom if you don't know what I'm talking about.

This is true at anything other then the lowest ISOs. But it's true for most (all?) crop sensors, and even the FF ones as the ISOs climb. You just have more ISOs where red doesn't suck on FF.

Quote
In reality, I find the ff has a 2-3 stop advantage over crop because with crop iso800 is the highest "safe" setting while with the 6d it's iso6400, and truth to be told I'd still prefer the latter if the dr is low.

The crop sensors are fine to about 3200, though I agree that Canon's FF sensors are 2+ stops better at high ISO.

Quote
* Viewfinder: Not directly sensor-iq related and last, but not least - the more expensive crop cameras have an somewhat ok vf, but with ff you see more of what you're shooting due to the larger mirror which is a reason for ff on its own as in "iq for your eye".

I don't notice a significant difference vs. the 7D, though what you say is true for the other crop models.

Quote
and of course for tele shots with 300mm * 1.6x crop factor which makes a decisive difference for wildlife.

It's hard to beat a "built in" 1.6x teleconverter  :)
Title: Re: Major IQ advantage of FF?
Post by: Cory on November 07, 2013, 06:35:53 AM
Thanks for all the responses.  Here's my "best of" flickr stream if you like:

http://www.flickr.com/photos/corysteiner/ (http://www.flickr.com/photos/corysteiner/)

Sticking with what I have for now, but I can maybe replace the body with a 70D and see what happens or replace my body and normal lens with a 6D and 35 or 50 prime and see what happens (my telephoto lenses are the 100 2.0 and 200 2.8 ). 

 :o ??? :-* 8) ;D
Title: Re: Major IQ advantage of FF?
Post by: docsmith on November 07, 2013, 06:43:25 AM
The "major" IQ advantage of FF is in high ISO noise.  There is an improvement of ~2 stops.  Which is to say, you get similar levels of noise at ISO 6400 on a current generation FF sensor as ISO 1600 on a current generation crop sensor. 

This past year I went from a 7D to a 5DIII.  I happily shot for years with the 7D.  It is a great camera.  I took many pictures that I proudly posted on the web and enlarged to 16x20 in prints.  People still come into my office and stop and stare at some of the pictures before they talk with me.  Crop sensors are very capable.

I upgraded for a couple of reasons.  First, the higher ISO performance.  I didn't want to use a flash as often as I was.  But I have also seen improvements, IMO, in color rendition, fine detail, highlight performance, and out-of focus blur (bokeh) using the same or similar lenses.  Regarding detail, I sometimes get shots that are so sharp, I could print them at 100% and they'd look good.  That was almost never true on the 7D.

So, P&S camera sensors are better than camera phones, crop sensors are much better than P&S cameras (2/3 sensors), FF is better than cropped sensors, and medium format gives even better images than FF.  So, phone>P&S>APS-C>FF>MF. 

You just need to pick where in that range your budget allows and you want to be...
Title: Re: Major IQ advantage of FF?
Post by: sanj on November 07, 2013, 06:56:23 AM
Of course full frame is better.

Why would you not shoot full frame? If you do not go overboard and limit yourself to say a 6D and a decent lens what would be the cost difference between this and crop? Not enough to matter in the long run.

However, better lenses are required, though shooting F/2 on APS-C is close to shooting F/2.8 on FF, which means the stopped down performance advantage with equal DOF is there with FF, but lenses tend to perform better on APS-C in regards to taking the good center IQ of a lens. I've compared shots with my 5DII + Sigma 35mm and a friend's X100, the images come so close to performance with image quality and ISO performance, my lens was sharper wide open and of course, I could go twice as shallow, but the colors and overall picture the X100 can put out with plain Jpegs are just marvelous, this made me reconsider the relevance of full frame for a while...
But, I'm comparing an FF from 2008 and a crop from 2010, so, smaller sensor cameras will outperform older larger sensor cameras, but in terms of latest tech the bigger sensor will outperform the smaller in ISO performance, color depth, DR etc. but it's all an eventual catch up game I believe

"All things being equal" implies we compare same manufactures, current sensors, lenses etc. Bottom line: Full frame is better.
Title: Re: Major IQ advantage of FF?
Post by: Pi on November 07, 2013, 08:00:23 AM
Unless you are FL (and cash) limited, FF provides much better IQ. Some people would not care, and that is OK. But if you do, you immediately notice:


Here is a graph with DXO data: the Canon 50/1.4 on the 7D (green) vs. the Canon 85/1.8 on the 5D2 (red), in equivalent apertures, center:
(http://plamen.emilstefanov.net/FFvsCrop_theory/graph1.png)

You see that the advantage is more noticeable near wide open, where the weakest resolution is. BTW, I was sloppy, and did not make the effort to draw better interpolated curves. The peaks of both curves are flattened.

Another comparison: the 135L on the 5DII vs. the 85L (twice the price!) on the 50D, in the center, using photozone.de data. The 70D would perform better, of course but not so much wide open - the limiting factor is the lens here. Again, equivalent apertures. The shorter green curve is the 85/1.8 on the 50D. 
(http://plamen.emilstefanov.net/FFvsCrop_theory/graph2.png)

And here: http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=397&Camera=736&Sample=0&FLI=0&API=0&LensComp=108&CameraComp=0&FLIComp=0&APIComp=0 (http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=397&Camera=736&Sample=0&FLI=0&API=0&LensComp=108&CameraComp=0&FLIComp=0&APIComp=0) is a visual evidence (crop camera: 60D). This picture is much more telling since you see the effect of the LoCA as well.

BTW, I used to have crop cameras, so I am speaking of experience, as well. You can follow the link in my profile for some 50D/5D2 comparisons (cameras of the same generation). You can see there some equivalent comparisons, and also how the 35L compares wide open on both (not equivalent shots, of course).

BTW, the theory that crop cameras use the better part of the lens is a myth, mostly. They do but they penalize you everywhere by the extra enlargement needed. That penalty is compensated a bit but the higher pixel density but this factor is not enough, most of the time. EF lenses do offer more uniform performance on crop than EF-S lenses but at the expense of some resolution.
Title: Re: Major IQ advantage of FF?
Post by: Ruined on November 07, 2013, 08:07:35 AM
I know that you get a more shallow DOF and better high ISO performance with a full frame over a crop, but with good lenses on either is there really much of an IQ difference all other things being equal.  I do get great results with my T1i, but I do see some ultra-great results out there that my camera just isn't capable of.  The sensible option is to remain with my crop-inspired lenses and maybe go to a 70D or the next Rebel, but the 6D seems pretty cool. 
I agonize over this stuff because I'm the opposite of a gear-hound.  I'm a minimalist who tries to do the most with the least so it's quality over quantity.  Thank you in advance for your wisdom.

In most cases, you will get better quality for full frame, but there are cases crop is better too.

If you are trying to frame something really far away and it fails to fill the frame of your full frame camera due to lack of reach, the crop camera will likely have better quality on said target as its reach will be better due to the crop factor & more pixels on the far away item.

Crop is also better in terms of lightness and cost, meaning you may not always want to take something as heavy and costly as full frame with you everywhere.

But, for most other situations full frame will produce a significantly better picture.  Consider though that for full frame its not just the cost of a 6D, but also the replacement zoom lenses that run $1000+ for quality ones, and $2000+ for really high quality ones.  So whether the improved picture is personally worth it will only likely be found with experimentation.

Personally, I'd advocate having both a full frame and a crop camera and using them for different scenarios.
Title: Re: Major IQ advantage of FF?
Post by: Marsu42 on November 07, 2013, 09:14:07 AM
* ff has more leverage for postprocessing, this is what matters the most to me. If you try to raise one color channel on a gradient (say lessen or intensify blue on a partly cloudy sky) the crop shot will immediately fall apart while the bigger ff pixels allow for more postprocessing creativity or fixing.
This is true but an exaggeration. Crop images do not 'immediately fall apart.' You have to push to see the difference.

Not to be misunderstood: The "immediately" is concerning color channel operation like pushing or reducing blue sky or green grass - otherwise of course you can do a lot of pp with crop shots unless you're drowning in iso noise.

Quote
In reality, I find the ff has a 2-3 stop advantage over crop because with crop iso800 is the highest "safe" setting while with the 6d it's iso6400, and truth to be told I'd still prefer the latter if the dr is low.
The crop sensors are fine to about 3200

This has been discussed to death, so no need to re-open pandora's box :-p but to clarify: I find iso800 the max. setting which doesn't make that much of a difference @100% crop if properly exposed, otherwise it's up to the specific subject, print/display size and subjective feeling when nr+sharpening results in too much of a plastic look.
Title: Re: Major IQ advantage of FF?
Post by: bdunbar79 on November 07, 2013, 03:45:37 PM
Ok, I know we're talking APS-C here, but have you ever shot at ISO 3200 and ISO 6400 with the 1D Mark IV?  Completely useable, if not underexposed.  I think this more speaks to Canon's flagship line manufacturing though, vs. the general category of APS-H sensors.  I have a lot of night football game shots at ISO 3200 with that camera that are probably not much different than the 1Dx shots at that ISO, same situation.  This is where I think a 1D4 with 300 f/2.8 might be a better choice than a 1Dx 300 f/2.8 but with cropping in post.  I could be wrong.
Title: Re: Major IQ advantage of FF?
Post by: gmrza on November 07, 2013, 04:45:31 PM

  • A lot of excellent lenses designed for FF.


This is especially apparent if you want to shoot at the shorter end of the focal length range.  You have better options available to you if shooting full frame than crop.  That said, I have still shot some decent landscapes with the 7D.

One good example is the 24-105 f/4 - being a full frame lens, it delivers best in terms of its overall flexibility on a full frame body.  On crop, you effectively lose out on the wide end, and you cannot shoot exposures as long hand-held as on full frame.  I have successfully shot 0.3s exposures with the 5DII and 24-105 f/4L IS USM hand-held.  I would not like my chances of achieving the same with the 7D.
If you were to move to the 17-55 f/2.8 IS USM on crop, you would lose the long end and the weather sealing.

Currently, if I want to shoot something quickly, I just pull the 7D out of the cupboard.  If I want to put more care into the shot, I reach for the 5DII or 5DIII.

Maybe on the weekend I can convince my son or daughter to pose and let me shoot with the 5DIII and 7D in the same light, using the same lens.  That would be a more valid comparison.  It would probably need to be in studio to guarantee the same lighting.
Title: Re: Major IQ advantage of FF?
Post by: Cory on November 07, 2013, 07:53:22 PM
Thanks again.  I think my options are:
- 70D with my current set of 17-55, 100 2.0 and 200 2.8II  or
- 6D (or used 5D Mk II) with (sell my 17-55 for) 35 2.0 IS, 100 2.0 and 200 2.8II
My main duty is indoor volleyball, but I also do a lot of street, landscape, travel, family, nature, etc.

 :-*
Title: Re: Major IQ advantage of FF?
Post by: AprilForever on November 07, 2013, 10:14:50 PM
I know that you get a more shallow DOF and better high ISO performance with a full frame over a crop, but with good lenses on either is there really much of an IQ difference all other things being equal.  I do get great results with my T1i, but I do see some ultra-great results out there that my camera just isn't capable of.  The sensible option is to remain with my crop-inspired lenses and maybe go to a 70D or the next Rebel, but the 6D seems pretty cool. 
I agonize over this stuff because I'm the opposite of a gear-hound.  I'm a minimalist who tries to do the most with the least so it's quality over quantity.  Thank you in advance for your wisdom.

All else being equal, a photosite is a photosite. A FF camera has a larger area, BUT...

Costs more
Has shallower depth of field (NOT always a good thing, ESPECIALLY with long lenses)
Wide angle lenses are WAY more expensive (there are superb crop lenses Tokin 11-16 for example)
lenses are not as long...
Heavier
Bulkier camera
Bulkier lenses

There are a lot of people jumping on the Micro four thirds bandwagon. check out Natureandphotography.com
The author there has ditched FF for smaller, far more usable gear. A camera is useless which is too bulky to use. If you ever feel like not picking up your camera because it is too heavy, consider the true price of FF...
Title: Re: Major IQ advantage of FF?
Post by: takesome1 on November 07, 2013, 10:37:01 PM
I know that you get a more shallow DOF and better high ISO performance with a full frame over a crop, but with good lenses on either is there really much of an IQ difference all other things being equal.

I'm a minimalist who tries to do the most with the least so it's quality over quantity.  Thank you in advance for your wisdom.

Shallow DOF and better high ISO performance improves IQ. Unless you hold to the thought that lens sharpness is the test of IQ. Both of these reasons are big positives to go with a FF body.

With equally framed identical FOV pictures with the same lens the IQ will be better out of the FF. The FF will put more pixels and larger pixels on the target than a crop body will. Larger pixels will take a larger sampling of available light. You will be closer to the subject in this situation and that will improve your IQ as well.

Only in those situations where you focal length limited would the crop body have an advantage. An example would be shooting distant objects with the longest lens you own.

So quality over quantity IMO would be to own a 6D with a 24-70mm f/2.8 II, instead of owning a t4i and a half dozen average lenses.
Title: Re: Major IQ advantage of FF?
Post by: abcde12345 on November 07, 2013, 11:47:24 PM
To be honest I've always been skeptical about the difference, but today after editing some of the pictures from a 6D I borrowed from someone, the IQ difference is amazing! I used the same lens for 6D and 550D, and I must say the sharpness, crisp, dynamic range, colour and "wow" effect is something I've never seen in my 550D. Given that it might be a skill thing, I am convinced now that the sensors do matter, and IQ will be the same if the same sensor is used in APS-C and FF cameras (I guess?), but the issue is that FF generally uses a different sensor, hence the difference.
Title: Re: Major IQ advantage of FF?
Post by: Pi on November 07, 2013, 11:57:39 PM
A FF camera has a larger area, BUT...
[...]
Has shallower depth of field (NOT always a good thing, ESPECIALLY with long lenses)

This is a misconception. FF does not have shallower DOF. It only has the option for less DOF when needed.
Title: Re: Major IQ advantage of FF?
Post by: AprilForever on November 08, 2013, 12:23:00 AM
A FF camera has a larger area, BUT...
[...]
Has shallower depth of field (NOT always a good thing, ESPECIALLY with long lenses)

This is a misconception. FF does not have shallower DOF. It only has the option for less DOF when needed.

Sure it has shallower depth of field 50mm at f4 on a 7D is roughly equivalent to 30mm f2.5 on a 5D. Same framing, shallower depth of field. When shooting birds in flight, I need usually f8 on a 7D to get the bird at least mostly in focus. On full frame? That's f13. To maintain shutter speed, that means ever rising ISO's.

Yes. The Hi ISO advantage disappears.

Title: Re: Major IQ advantage of FF?
Post by: Pi on November 08, 2013, 12:39:11 AM
This is a misconception. FF does not have shallower DOF. It only has the option for less DOF when needed.
When shooting birds in flight, I need usually f8 on a 7D to get the bird at least mostly in focus. On full frame? That's f13. To maintain shutter speed, that means ever rising ISO's.

Yes. The Hi ISO advantage disappears.

And the "shallow DOF disadvantage" disappears, too. There is a reason those are called equivalent settings.
Title: Re: Major IQ advantage of FF?
Post by: J.R. on November 08, 2013, 12:52:51 AM
A FF camera has a larger area, BUT...
[...]
Has shallower depth of field (NOT always a good thing, ESPECIALLY with long lenses)

This is a misconception. FF does not have shallower DOF. It only has the option for less DOF when needed.

Sure it has shallower depth of field 50mm at f4 on a 7D is roughly equivalent to 30mm f2.5 on a 5D. Same framing, shallower depth of field. When shooting birds in flight, I need usually f8 on a 7D to get the bird at least mostly in focus. On full frame? That's f13. To maintain shutter speed, that means ever rising ISO's.

Yes. The Hi ISO advantage disappears.



And that is just plain BS you are talking. Assuming that you are taking a photograph of a bird with a 400mm lens 50 feet away. Let's see how the DOF works out at f/8 with the 5D3 and the 7D -

7D: Total DOF is 1.41 feet
5D3: Total DOF is 2.23 feet
Title: Re: Major IQ advantage of FF?
Post by: Hillsilly on November 08, 2013, 01:51:28 AM
I enter monthly club photo competitions.  When you view the entries, you have no idea what type of camera was used, the settings, the lens etc.  Yet I know that other photos are taken with a mixture of FF and APS-C cameras.  There's even the occasional film camera and P & S.  But usually its almost impossible to tell what type of camera was used.  And in 100% of cases, from a viewer's perspective, it is irrelevant, because you are only interested in the final result.  You're more concerned with impact, emotion, etc.

But from the photographers perspective, choice of camera is very relevant.  If your final result relates to an image in low light, fast action, taken in the rain, needs particular lenses, etc then things are so much easier if you are using the right tool for the job.  Given that FF cameras have traditionally been more feature packed, apart from IQ, there are a lot of other reasons why they might be the best choice for someone.  Just as in many situations, a crop camera is the best choice.

In summary - when viewing the final result, nobody cares what camera you used.  But choosing the right camera makes it easier to get the best final result.
Title: Re: Major IQ advantage of FF?
Post by: AlanF on November 08, 2013, 02:23:22 AM
A FF camera has a larger area, BUT...
[...]
Has shallower depth of field (NOT always a good thing, ESPECIALLY with long lenses)

This is a misconception. FF does not have shallower DOF. It only has the option for less DOF when needed.

Sure it has shallower depth of field 50mm at f4 on a 7D is roughly equivalent to 30mm f2.5 on a 5D. Same framing, shallower depth of field. When shooting birds in flight, I need usually f8 on a 7D to get the bird at least mostly in focus. On full frame? That's f13. To maintain shutter speed, that means ever rising ISO's.

Yes. The Hi ISO advantage disappears.



And that is just plain BS you are talking. Assuming that you are taking a photograph of a bird with a 400mm lens 50 feet away. Let's see how the DOF works out at f/8 with the 5D3 and the 7D -

7D: Total DOF is 1.41 feet
5D3: Total DOF is 2.23 feet

I think that there are circles of confusion here! It seems pretty obvious that if you have the same lens it gives the same size image on crop and FF sensors, and if the two images are viewed at the same size on a screen or print they will have exactly the same depth of field. If they are not enlarged, but the FF is viewed at a smaller size, it will only appear to have a greater depth of field.

The arithmetic from the DOF calculator proves that the images have the same depth of field when viewed at the same size. The depth of field is calculated from the size of the circle of confusion. For the 5DIII it is 0.03 mm, for the 1.6x crop 7D it is 0.019. And 0.03/0.019 = 1.6. So, when you enlarge the FF image 1.6x to get the same size image as the crop, you exactly compensate for the difference in circles of confusion.

Similarly, look at the ratios of total DOF of the 5D3 to 7D. It equals 2.23/1.41 = 1.6. The image from FF has to be enlarged 1.6x to give the same size print as the crop, and in doing so you multiply the out of focus regions 1.6x and so reduce the depth of field 1.6x. 

Edit: to avoid confusion - what I am talking about is taking. say, a photo of a bird in flight, and cropping the bird in flight on the FF to be the same size as that taken directly on the crop. Then, they should have the same depth of field.
Title: Re: Major IQ advantage of FF?
Post by: Zlyden on November 08, 2013, 02:33:52 AM
And that is just plain BS you are talking. Assuming that you are taking a photograph of a bird with a 400mm lens 50 feet away. Let's see how the DOF works out at f/8 with the 5D3 and the 7D -

7D: Total DOF is 1.41 feet
5D3: Total DOF is 2.23 feet

Yes (as someone else probably already mentioned), you should count in crop factor of x1.6 and compare "Focal length (mm): 400 mm" on cropped 7D with "Focal length (mm): ~ 640 mm" on FF 5Ds.

After that you will see that to get "equivalent" DOF, you need to stop 5D down to f/13...
Title: Re: Major IQ advantage of FF?
Post by: J.R. on November 08, 2013, 02:42:09 AM
And that is just plain BS you are talking. Assuming that you are taking a photograph of a bird with a 400mm lens 50 feet away. Let's see how the DOF works out at f/8 with the 5D3 and the 7D -

7D: Total DOF is 1.41 feet
5D3: Total DOF is 2.23 feet

Yes (as someone else probably already mentioned), you should count in crop factor of x1.6 and compare "Focal length (mm): 400 mm" on cropped 7D with "Focal length (mm): ~ 640 mm" on FF 5Ds.

After that you will see that to get "equivalent" DOF, you need to stop 5D down to f/13...

AprilForever wasn't talking about equivalence so I guess you missed the point. In fact, while doing the IQ comparisons, it is almost always assumed that you need to crop the FF image to make it equivalent to the APS-C image ... If that is mandatory, why buy a FF in the first place?
Title: Re: Major IQ advantage of FF?
Post by: J.R. on November 08, 2013, 02:49:16 AM
A FF camera has a larger area, BUT...
[...]
Has shallower depth of field (NOT always a good thing, ESPECIALLY with long lenses)

This is a misconception. FF does not have shallower DOF. It only has the option for less DOF when needed.

Sure it has shallower depth of field 50mm at f4 on a 7D is roughly equivalent to 30mm f2.5 on a 5D. Same framing, shallower depth of field. When shooting birds in flight, I need usually f8 on a 7D to get the bird at least mostly in focus. On full frame? That's f13. To maintain shutter speed, that means ever rising ISO's.

Yes. The Hi ISO advantage disappears.



And that is just plain BS you are talking. Assuming that you are taking a photograph of a bird with a 400mm lens 50 feet away. Let's see how the DOF works out at f/8 with the 5D3 and the 7D -

7D: Total DOF is 1.41 feet
5D3: Total DOF is 2.23 feet

I think that there are circles of confusion here! It seems pretty obvious that if you have the same lens it gives the same size image on crop and FF sensors, and if the two images are viewed at the same size on a screen or print they will have exactly the same depth of field. If they are not enlarged, but the FF is viewed at a smaller size, it will only appear to have a greater depth of field.

The arithmetic from the DOF calculator proves that the images have the same depth of field when viewed at the same size. The depth of field is calculated from the size of the circle of confusion. For the 5DIII it is 0.03 mm, for the 1.6x crop 7D it is 0.019. And 0.03/0.019 = 1.6. So, when you enlarge the FF image 1.6x to get the same size image as the crop, you exactly compensate for the difference in circles of confusion.

Similarly, look at the ratios of total DOF of the 5D3 to 7D. It equals 2.23/1.41 = 1.6. The image from FF has to be enlarged 1.6x to give the same size print as the crop, and in doing so you multiply the out of focus regions 1.6x and so reduce the depth of field 1.6x.

If talking in terms of equivalence, yes.
Title: Re: Major IQ advantage of FF?
Post by: Zlyden on November 08, 2013, 03:23:40 AM
AprilForever wasn't talking about equivalence so I guess you missed the point.

Maybe.

As I understand the meaning was:

"To get the similar image of some bird on FF body, you will need a longer lens and smaller aperture value, that makes higher ISO advantage less obvious"
(close enough?)

And this is really one the things crop-to-FF switcher should take into account (or at least -- not forget about).

PS: I did myself made a switch from old 400D to 6D about a month ago ;D) (that should explain my interest to the topic).

So far I'm quite happy with 6D -- it's amazing how the lenses I used to play with for 4-6 years on 400D (24-105, 70-300, 50/1.8II) started to make very different pictures. It really adds new level of fun to amateurish hobby (one of the things that makes the switch "worth it" for those who did not have FF bodies before). I would avoid using phrases like "Major IQ advantage".

But, I'm not sure yet if I'm happy with 17-40 that I had to get to replace cropped 10-22...
Title: Re: Major IQ advantage of FF?
Post by: AlanF on November 08, 2013, 03:53:31 AM
A FF camera has a larger area, BUT...
[...]
Has shallower depth of field (NOT always a good thing, ESPECIALLY with long lenses)

This is a misconception. FF does not have shallower DOF. It only has the option for less DOF when needed.

Sure it has shallower depth of field 50mm at f4 on a 7D is roughly equivalent to 30mm f2.5 on a 5D. Same framing, shallower depth of field. When shooting birds in flight, I need usually f8 on a 7D to get the bird at least mostly in focus. On full frame? That's f13. To maintain shutter speed, that means ever rising ISO's.

Yes. The Hi ISO advantage disappears.



And that is just plain BS you are talking. Assuming that you are taking a photograph of a bird with a 400mm lens 50 feet away. Let's see how the DOF works out at f/8 with the 5D3 and the 7D -

7D: Total DOF is 1.41 feet
5D3: Total DOF is 2.23 feet

I think that there are circles of confusion here! It seems pretty obvious that if you have the same lens it gives the same size image on crop and FF sensors, and if the two images are viewed at the same size on a screen or print they will have exactly the same depth of field. If they are not enlarged, but the FF is viewed at a smaller size, it will only appear to have a greater depth of field.

The arithmetic from the DOF calculator proves that the images have the same depth of field when viewed at the same size. The depth of field is calculated from the size of the circle of confusion. For the 5DIII it is 0.03 mm, for the 1.6x crop 7D it is 0.019. And 0.03/0.019 = 1.6. So, when you enlarge the FF image 1.6x to get the same size image as the crop, you exactly compensate for the difference in circles of confusion.

Similarly, look at the ratios of total DOF of the 5D3 to 7D. It equals 2.23/1.41 = 1.6. The image from FF has to be enlarged 1.6x to give the same size print as the crop, and in doing so you multiply the out of focus regions 1.6x and so reduce the depth of field 1.6x.

If talking in terms of equivalence, yes.

I am not sure that he is talking "plain BS". If you obtain the same field of view on the FF as on the 1.6x crop by either standing 1.6x closer with the FF or use a 1.6x longer lens, the crop has 1.6x greater DOF (calculated on the DOF calculator you used). If, as we have agreed, you crop the FF from the same distance with the same lens, 1.6x, then the cropped FF has the same DOF as the crop sensor.
Title: Re: Major IQ advantage of FF?
Post by: aj1575 on November 08, 2013, 04:38:19 AM
  The sensible option is to remain with my crop-inspired lenses and maybe go to a 70D or the next Rebel, but the 6D seems pretty cool. 
There are mainly two questions you need to answer. First, and most important; how much money do you like to spend on a tool you do not need to make a living out of. I think you know this, since the 70D and the 6D are not so far appart on the price scale.
The second qustion is, what you like to do with the camera and the file; are you an allround shooter, or do specialize in something; do you need/like to make large prints, or do you almost only make smaller prints.

FF (the 6D) will give an advantage in IQ; you will see this especially at high ISO and in large prints. With smaller prints and at lower ISO the difference is rather small. On the screen APS-C pictures can look quite nasty when zommed to 100% (my 70D files at high ISO do so), but at 20MP the resolution is so high, that it does not really matter in normal prints.
On the other hand, the 70D has a very nice AF-system, a cool touch screen (this is no toy, it really improves the handling), the higher frame rate, and other nice features.

If you are a landscape or architecture photograph, then I would go for the 6D. The IQ is great, but it is not a "fast" camera. The 70D is more of an allround package, with a little disadvantage in IQ; which is okay when you do not need large prints.
Title: Re: Major IQ advantage of FF?
Post by: J.R. on November 08, 2013, 04:44:14 AM
A FF camera has a larger area, BUT...
[...]
Has shallower depth of field (NOT always a good thing, ESPECIALLY with long lenses)

This is a misconception. FF does not have shallower DOF. It only has the option for less DOF when needed.

Sure it has shallower depth of field 50mm at f4 on a 7D is roughly equivalent to 30mm f2.5 on a 5D. Same framing, shallower depth of field. When shooting birds in flight, I need usually f8 on a 7D to get the bird at least mostly in focus. On full frame? That's f13. To maintain shutter speed, that means ever rising ISO's.

Yes. The Hi ISO advantage disappears.



And that is just plain BS you are talking. Assuming that you are taking a photograph of a bird with a 400mm lens 50 feet away. Let's see how the DOF works out at f/8 with the 5D3 and the 7D -

7D: Total DOF is 1.41 feet
5D3: Total DOF is 2.23 feet

I think that there are circles of confusion here! It seems pretty obvious that if you have the same lens it gives the same size image on crop and FF sensors, and if the two images are viewed at the same size on a screen or print they will have exactly the same depth of field. If they are not enlarged, but the FF is viewed at a smaller size, it will only appear to have a greater depth of field.

The arithmetic from the DOF calculator proves that the images have the same depth of field when viewed at the same size. The depth of field is calculated from the size of the circle of confusion. For the 5DIII it is 0.03 mm, for the 1.6x crop 7D it is 0.019. And 0.03/0.019 = 1.6. So, when you enlarge the FF image 1.6x to get the same size image as the crop, you exactly compensate for the difference in circles of confusion.

Similarly, look at the ratios of total DOF of the 5D3 to 7D. It equals 2.23/1.41 = 1.6. The image from FF has to be enlarged 1.6x to give the same size print as the crop, and in doing so you multiply the out of focus regions 1.6x and so reduce the depth of field 1.6x.

If talking in terms of equivalence, yes.

I am not sure that he is talking "plain BS". If you obtain the same field of view on the FF as on the 1.6x crop by either standing 1.6x closer with the FF or use a 1.6x longer lens, the crop has 1.6x greater DOF (calculated on the DOF calculator you used). If, as we have agreed, you crop the FF from the same distance with the same lens, 1.6x, then the cropped FF has the same DOF as the crop sensor.

Again, in terms of equivalence, yes. But my point remains that there is a lot of assumption going into the fact that the image has to be cropped by 1.6x.

On second reading I agree that it isn't really "plain BS" as I wrote above. Under the assumption that you would be cropping the FF image to match the APS-C FOV, AprilForever is correct.
Title: Re: Major IQ advantage of FF?
Post by: Marsu42 on November 08, 2013, 04:56:57 AM
Yes. The Hi ISO advantage disappears.

I wouldn't know about you guys with the big lenses, but I know this is true for macro - shooting near 1:1 with a ff has a so much thinner dof that a crop is at least equivalent in terms of required iso, plus the crop has got the longer working distance.

Edit: One more note: High iso on ff is *NOT* equivalent to low iso on crop because the higher iso always has less dynamic range - so the advantage not only disappears, but a disadvantage appears :-o
Title: Re: Major IQ advantage of FF?
Post by: AlanF on November 08, 2013, 05:04:47 AM
J.R.
Thanks. The discussion got me thinking and I learned something. 
Title: Re: Major IQ advantage of FF?
Post by: Zlyden on November 08, 2013, 05:53:08 AM
One more note: High iso on ff is *NOT* equivalent to low iso on crop because the higher iso always has less dynamic range - so the advantage not only disappears, but a disadvantage appears :-o

Great point!

But...

...if instead of "equivalent" we will use more relaxed conceptions like "practical purpose" (that also deals with usability of details, noise, etc. in final image), then a picture shot at ISO 1600 on FF is roughly similar to ones made at ISO 400 on Canon's crops (or FF picture shot at ISO 12800 looks as bad as crop's picture at ISO 3200).

There are lenses like this notorious Sigma 18-35/1.8 that could be considered as an alternate "path to higher IQ" with lower ISO settings for crop camera users. But this lens's size, weight and not-nice reviews about AF precision make it even more difficult decision than "just go and buy 6D body, now you can get for $1600 un-kitted, yes, it does not have touch screen, but features GPS instead" :)
Title: Re: Major IQ advantage of FF?
Post by: J.R. on November 08, 2013, 06:45:41 AM
Yes. The Hi ISO advantage disappears.

I wouldn't know about you guys with the big lenses, but I know this is true for macro - shooting near 1:1 with a ff has a so much thinner dof that a crop is at least equivalent in terms of required iso, plus the crop has got the longer working distance.

Edit: One more note: High iso on ff is *NOT* equivalent to low iso on crop because the higher iso always has less dynamic range - so the advantage not only disappears, but a disadvantage appears :-o

I doubt whether it is as easy as it sounds. Diffraction sets in quite early with crop - 60D is rated at f/6.9 as opposed to the FF - f/10.1 - How that may work out in Macro is an animal new to me. 

Most of the macro (to me at least, YMMV) is done using a tripod or some form of support (unless of course you are shooting ants lying down on your belly) so the ISO performance is put into question while doing macro only in specific scenarios.

Note: Regardless of my arguing that FF is better, I'm looking forward to the 7D II because in certain focal length limited scenarios where light is adequate, using the crop will provide better images.
Title: Re: Major IQ advantage of FF?
Post by: ajfotofilmagem on November 08, 2013, 07:18:24 AM
I photographed several weddings with Fuji film Provalue ISO 200 on my Canon 300V. Soon after came the Rebel XT, and I tested it grudgingly because the colors of the film Fuji and TTL metering more precise in my Canon 300V give superior results. One thing though encouraged me to abandon the film later: With film (same DOF of full frame) I was forced to use almost all the time F5.6 for groups of people, and digital APS-C I had the same DOF using F3.5. ::) Over time digital cameras were the best , and good films left the market . Today I do not think going back to the DOF with full frame digital, and getting arrested again opening F5.6 for groups of people. For my use , APS-C gives the DOF I need and finally F2.8 lenses are useful. What's the point of having lenses F2.8 and can not use F2.8 because of the extremely shallow DOF? Therefore I say that not everyone will make the leap to full frame someday. I do not intend to do that, and I know I'm not the only one.
Title: Re: Major IQ advantage of FF?
Post by: candc on November 08, 2013, 07:26:40 AM
this subject gets way over analyzed. if you take a photo with a lens on ff and crop out a square or put it on a crop body, it is the same.
in order to frame a scene the same way with a crop body as ff you either use shorter fl or stand further away, both of which increase dof
Title: Re: Major IQ advantage of FF?
Post by: ajfotofilmagem on November 08, 2013, 07:38:36 AM
this subject gets way over analyzed. if you take a photo with a lens on ff and crop out a square or put it on a crop body, it is the same.
in order to frame a scene the same way with a crop body as ff you either use shorter fl or stand further away, both of which increase dof
What you say is correct but is not suitable. ::) Reading my comment just above, one realizes that to get deeper DOF on full frame I used F5.6 or F8 to photograph groups of people (at different distances) at wedding parties. According to your suggestion, I could use a 16mm lens on full frame, and accept all geometric distortion of such a lens. :( Or take more away (in a tight room?) to simulate the DOF of APS-C I want. ???
Title: Re: Major IQ advantage of FF?
Post by: Zlyden on November 08, 2013, 08:53:55 AM
if you take a photo with a lens on ff and crop out a square or put it on a crop body, it is the same.

This was exactly the reason why 6D is the camera I choose to finally replace my 400D with.

If I will not be comfortable with first FF pictures I make, I can just crop 10 megapixels from the center of the images to get what in theory should be the same picture size as that of 400D :)

Of course, it would be better if Canon did such thing for me: just cut 10MP piece from 6D hi-ISO sensor and put it into small APS-C body + magic center AF point that can focus in total darkness. No movies, live-view, touch-screen, wifi-GPS? Perfect -- Oh, thank you very much! This could be an ideal 400D replacement, that I would buy without a second thought for current 6D price tag. (But, better if such camera would be in "kids-toys" class for $300-500. Call it, please, "1200D" or "110D").  :P
Title: Re: Major IQ advantage of FF?
Post by: takesome1 on November 08, 2013, 09:16:46 AM
A FF camera has a larger area, BUT...
[...]
Has shallower depth of field (NOT always a good thing, ESPECIALLY with long lenses)

This is a misconception. FF does not have shallower DOF. It only has the option for less DOF when needed.

Sure it has shallower depth of field 50mm at f4 on a 7D is roughly equivalent to 30mm f2.5 on a 5D. Same framing, shallower depth of field. When shooting birds in flight, I need usually f8 on a 7D to get the bird at least mostly in focus. On full frame? That's f13. To maintain shutter speed, that means ever rising ISO's.

Yes. The Hi ISO advantage disappears.



And that is just plain BS you are talking. Assuming that you are taking a photograph of a bird with a 400mm lens 50 feet away. Let's see how the DOF works out at f/8 with the 5D3 and the 7D -

7D: Total DOF is 1.41 feet
5D3: Total DOF is 2.23 feet

I think that there are circles of confusion here! It seems pretty obvious that if you have the same lens it gives the same size image on crop and FF sensors, and if the two images are viewed at the same size on a screen or print they will have exactly the same depth of field. If they are not enlarged, but the FF is viewed at a smaller size, it will only appear to have a greater depth of field.

The arithmetic from the DOF calculator proves that the images have the same depth of field when viewed at the same size. The depth of field is calculated from the size of the circle of confusion. For the 5DIII it is 0.03 mm, for the 1.6x crop 7D it is 0.019. And 0.03/0.019 = 1.6. So, when you enlarge the FF image 1.6x to get the same size image as the crop, you exactly compensate for the difference in circles of confusion.

Similarly, look at the ratios of total DOF of the 5D3 to 7D. It equals 2.23/1.41 = 1.6. The image from FF has to be enlarged 1.6x to give the same size print as the crop, and in doing so you multiply the out of focus regions 1.6x and so reduce the depth of field 1.6x.

If talking in terms of equivalence, yes.

I am not sure that he is talking "plain BS". If you obtain the same field of view on the FF as on the 1.6x crop by either standing 1.6x closer with the FF or use a 1.6x longer lens, the crop has 1.6x greater DOF (calculated on the DOF calculator you used). If, as we have agreed, you crop the FF from the same distance with the same lens, 1.6x, then the cropped FF has the same DOF as the crop sensor.

Sure you can crop your picture and get the same DOF. But then you have turned your FF camera in to a crop body. The amount of sensor you use is the same on both. The difference then is that you have a FF body that you are using fewer pixels on the subject.

But who does this? The whole point is silly because who buys a FF camera with the intention of cropping the pictures down to crop body size.

Title: Re: Major IQ advantage of FF?
Post by: neuroanatomist on November 08, 2013, 09:34:44 AM
if you take a photo with a lens on ff and crop out a square or put it on a crop body, it is the same.

Not quite the same - given that current FF sensors generally have lower pixel density than current APS-C sensors, your cropped FF image will have lower MP than the APS-C image.  For example, a 5DIII image cropped to APS-C framing will have 8.6 MP.  If that lower resolution is sufficient for your output purposes, there's no difference.  But also consider a focal length limited situation in which even the APS-C sensor doesn't provide sufficiently close framing, and you need to crop the APS-C image to 50% of it's original size.  The corresponding crop of the FF image will not have sufficient resolution for 100% display on some current montitors. 

Edit: One more note: High iso on ff is *NOT* equivalent to low iso on crop because the higher iso always has less dynamic range - so the advantage not only disappears, but a disadvantage appears :-o

You seem to be assuming the DR at equal ISO settings is the same on both FF and APS-C, but it's not.  Yes, raising the ISO reduces DR, but the DR of FF is higher to begin with (see below), which mitigates the 'disadvantage that appears'.  For example, at ISO settings above 800, the 5DIII has ~1 stop more DR than the 70D, so when you raise the ISO to compensate for the narrower aperture, you're not incurring a significant reduction in DR (<0.3 EV). 

The upshot is that if you can frame the subject identically, FF has a substantial advantage in terms of IQ.  If you need to crop to APS-C framing because you're focal length limited, there's no significant difference at low ISOs (up to ~800), and at higher ISOs the FF has a progressively bigger advantage, provided the cropped image has sufficient resolution to meet your output needs.
Title: Re: Major IQ advantage of FF?
Post by: candc on November 08, 2013, 10:18:54 AM
if you take a photo with a lens on ff and crop out a square or put it on a crop body, it is the same.

Not quite the same - given that current FF sensors generally have lower pixel density than current APS-C sensors, your cropped FF image will have lower MP than the APS-C image.  For example, a 5DIII image cropped to APS-C framing will have 8.6 MP.  If that lower resolution is sufficient for your output purposes, there's no difference.  But also consider a focal length limited situation in which even the APS-C sensor doesn't provide sufficiently close framing, and you need to crop the APS-C image to 50% of it's original size.  The corresponding crop of the FF image will not have sufficient resolution for 100% display on some current montitors. 

Edit: One more note: High iso on ff is *NOT* equivalent to low iso on crop because the higher iso always has less dynamic range - so the advantage not only disappears, but a disadvantage appears :-o

You seem to be assuming the DR at equal ISO settings is the same on both FF and APS-C, but it's not.  Yes, raising the ISO reduces DR, but the DR of FF is higher to begin with (see below), which mitigates the 'disadvantage that appears'.  For example, at ISO settings above 800, the 5DIII has ~1 stop more DR than the 70D, so when you raise the ISO to compensate for the narrower aperture, you're not incurring a significant reduction in DR (<0.3 EV). 

The upshot is that if you can frame the subject identically, FF has a substantial advantage in terms of IQ.  If you need to crop to APS-C framing because you're focal length limited, there's no significant difference at low ISOs (up to ~800), and at higher ISOs the FF has a progressively bigger advantage, provided the cropped image has sufficient resolution to meet your output needs.

What I meant is they are the same in regards to dof. Another thing to remember is with the higher pixel density on the crop bodies you need to use a sharp lens or the sensor out resolves the lens.
Title: Re: Major IQ advantage of FF?
Post by: luckydude on November 08, 2013, 10:21:07 AM
I've got both a 7D and a 5DIII.  I like doing wildlife so you would think I grab the 7D over the 5D.  Not so much.

The 5D is much sharper to the point that I can just crop to get the picture I want with the 5D. 

I've played with camera settings, cranking up the sharpening in the 7D helped a little but it struggles compared
to the 5d.  A lot.

That said, if Canon comes out with a 7DII that was "nothing" more than a 5DIII w/ a crop sensor (a good one, one that really gave me the 1.6x tele boost), I'd happily pay $3K for that.  In a heartbeat.  But the current 7D isn't remotely close to as good as the 5DIII in my opinion.
Title: Re: Major IQ advantage of FF?
Post by: mackguyver on November 08, 2013, 10:50:55 AM
I've got both a 7D and a 5DIII.  I like doing wildlife so you would think I grab the 7D over the 5D.  Not so much.

The 5D is much sharper to the point that I can just crop to get the picture I want with the 5D. 

I've played with camera settings, cranking up the sharpening in the 7D helped a little but it struggles compared
to the 5d.  A lot.

That said, if Canon comes out with a 7DII that was "nothing" more than a 5DIII w/ a crop sensor (a good one, one that really gave me the 1.6x tele boost), I'd happily pay $3K for that.  In a heartbeat.  But the current 7D isn't remotely close to as good as the 5DIII in my opinion.
Same here.  I do lots of wildlife shooting and when I picked up a 5DIII, I thought I'd sell my 5DII and keep my 7D.  After comparing them for several weeks, I realized that the 5DII files were much better than the 7D, even in good light and it was much easier to work with them in post.  I sold the 7D and upgraded my 1.4x II to a 1.4x III and though I still lose some distance, the 5DII and especially 5DIII with the 1.4x or 2x is noticeably better than the 7D files at all ISOs.  The FF bodies have almost no noise from ISO 100-800, while the 7D gets noisy at 400 and only gets worse.

I shot with crops for years, and they are very good, but if you have the money, it's better spent on a FF body, at least as things stand today.
Title: Re: Major IQ advantage of FF?
Post by: David_in_Seattle on November 08, 2013, 11:27:21 AM

What I meant is they are the same in regards to dof. Another thing to remember is with the higher pixel density on the crop bodies you need to use a sharp lens or the sensor out resolves the lens.

It's not the same in regards to Depth of Field.  At the same focal lengths a full frame sensor will have approximately 1 1/3 stop more depth of field than a crop sensor because of the difference in physical size.

Example:
FF at 50mm vs. Crop (31mm * 1.6 = 49.6mm) - The FF camera will always have the advantage in shallower DOF because the physical size of the sensor is more than twice that of the cropped sensor camera.  The larger sensor size allows for more angles of light to hit the sensor at the same aperture and focal length.  The more angles of light that are able to hit the sensor allows for a shallower depth of field.  I would have added the Depth of Field and Depth of Focus formulas to provide an accurate calculation, but I don't know how to add the special characters...so I recommend searching for it on Google.





Title: Re: Major IQ advantage of FF?
Post by: Cory on November 08, 2013, 11:30:14 AM
OK, I think I have it figured out.  I would like a 6D without wifi or GPS, but with the focusing-system of the 70D.
Thanks, Canon, in advance of bringing this to the market.  Will it be this month?
Title: Re: Major IQ advantage of FF?
Post by: J.R. on November 08, 2013, 11:41:52 AM
OK, I think I have it figured out.  I would like a 6D without wifi or GPS, but with the focusing-system of the 70D.
Thanks, Canon, in advance of bringing this to the market.  Will it be this month?

Good luck!
Title: Re: Major IQ advantage of FF?
Post by: Zlyden on November 08, 2013, 11:56:36 AM
I would like a 6D without wifi or GPS, but with the focusing-system of the 70D.

Do you mean 'Dual Pixel CMOS AF' or 70D viewfinder's 19 points AF (that is supposed to be the same as 7D's)?

The second one makes little sense (just like 'outer points' of current 6D AF system, that have placement more appropriate for APS-C camera): all of them points are cluttered to the center to make the camera body cheaper and smaller -- so, you can just use the center point and forget about the rest.

The first one will benefit more future Canon's 'mirrorless FF camera'.

I do hope that we will see 'mirrorless FF' from both Canon and Nikon on next year's Photokina. It will be called 'EOS L', 'EOS XL' or "EOS XXL", depending on the sensor MPs and price...  ;D
Title: Re: Major IQ advantage of FF?
Post by: Cory on November 08, 2013, 12:00:37 PM
Damn it.  70D it is then.
Very much appreciated the insight.  Every bit of it was exceptional.
Thanks again.
Title: Re: Major IQ advantage of FF?
Post by: AprilForever on November 08, 2013, 12:22:53 PM
Yes. The Hi ISO advantage disappears.

I wouldn't know about you guys with the big lenses, but I know this is true for macro - shooting near 1:1 with a ff has a so much thinner dof that a crop is at least equivalent in terms of required iso, plus the crop has got the longer working distance.

Edit: One more note: High iso on ff is *NOT* equivalent to low iso on crop because the higher iso always has less dynamic range - so the advantage not only disappears, but a disadvantage appears :-o

Well said, sir! I had not thought of that!
Title: Re: Major IQ advantage of FF?
Post by: Zlyden on November 08, 2013, 01:19:20 PM
Damn it.  70D it is then.

Here is another 'nonsense comment' that may or may not help to those who decide on crop-to-FF switch:

It was easier for me to buy 6D as 400D replacement =

1) I thought about replacing 400D for last 5 years with a camera that either has better ISO/indor-focusing or a camera that is smaller and lighter than 400D. So, during this year I kept 3 cameras in my list of possible candidates: 6D, 100D, EOS M, Powershot G1 X.

I shoot mostly two types of pictures: printing equipment (like Heidelberg or Xerox presses) in printing factories or at exhibitions (for my magazine review job) and architecture/landscapes (while traveling/vacations). I do not shoot birds, football players, other types of animals, planes, fast moving cars, moon, etc. unless I have no other choice. (Maybe some fish and turtles with G7 in water-box...)

2) About two months ago my wife complained that our small G7 'is not wide enough' for her to shoot European cathedrals (while she travels by herself with our small camera). I was overjoyed by such a comment and used it as excuse to buy EOS M two-lens-kit+11-22 as G7 replacement.  :D

3) EOS M is a great camera! Cheap, small and light (both body and lenses). Arguably: "the best amateur camera Canon ever made".

It has cool touch screen: you can compose a picture, than tap a finger in the area you want it to focus and press down the shutter button. Done! No more usual "zoom-focus-recompose-then-zoom-focus-recompose-again".

4) But EOS M's APS-C sensor has the same limitation as other cropped-sensor cameras: pictures at ISO 1600 (and above) are close to unusable because of too high noise level (and not very high dynamic range).

5) After getting EOS M as a replacement for G7, to replace 400D with any other Canon's cropped camera made no sense. 6D was the next logical choice of 'equivalent type of replacement'. And, yes, I'm happy that I made it. Now I can be busy to relearn how to use the lenses I already have, what settings to use now and then. Great! :)

6) We also plan to spend next New Year's vacation in Iceland (with 4 hours of dim light at day and possible northern lights at night). 6D looks much more like a capable camera for such conditions than 400D, EOS M and the rest of the cropped crowd...

Edit: changed the first sentence wording to make the rest of the post more relevant :)
Title: Re: Major IQ advantage of FF?
Post by: Cory on November 08, 2013, 01:32:46 PM
Damn it.  70D it is then.

Another 'nonsense comment' that may or may not help to those who decide on crop-to-FF switch

Nothing personal.  Ultimately, I realized the "focal length" issue of my current lenses with the 1.6x effect and how perfect the rented 100-400 (x1.6) was on a recent vacation.   
Clearly, then, the only real answer is the 70D now without adding any new lenses (except for maybe my very own 100-400) and then a full-frame and the appropriate "non-sports" lens when finances aren't an issue (which I'm hard at work on).
Just occured to me that the 7DII is on the horizon.  Oh cr*p.

 :-* :-* :-* :-* :-*
Title: Re: Major IQ advantage of FF?
Post by: Pi on November 08, 2013, 11:32:35 PM
I wouldn't know about you guys with the big lenses, but I know this is true for macro - shooting near 1:1 with a ff has a so much thinner dof that a crop is at least equivalent in terms of required iso, plus the crop has got the longer working distance.

At 1:1, FF has greater DOF (but the enlargement is less, of course).

Quote
Edit: One more note: High iso on ff is *NOT* equivalent to low iso on crop because the higher iso always has less dynamic range - so the advantage not only disappears, but a disadvantage appears :-o

Not true when comparing different formats and largely dependent on the sensor manufacturer.
Title: Re: Major IQ advantage of FF?
Post by: Pi on November 08, 2013, 11:42:04 PM
Nothing personal.  Ultimately, I realized the "focal length" issue of my current lenses with the 1.6x effect and how perfect the rented 100-400 (x1.6) was on a recent vacation.   
Clearly, then, the only real answer is the 70D now without adding any new lenses (except for maybe my very own 100-400) and then a full-frame and the appropriate "non-sports" lens when finances aren't an issue (which I'm hard at work on).

The 100-400 is not a terribly sharp lens, and the increased pixel density of the crop camera does not help so much. See this:

http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=113&Camera=453&Sample=0&FLI=7&API=0&LensComp=113&CameraComp=736&SampleComp=0&FLIComp=7&APIComp=1 (http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=113&Camera=453&Sample=0&FLI=7&API=0&LensComp=113&CameraComp=736&SampleComp=0&FLIComp=7&APIComp=1)

If you enlarge the FF image by 60%,  it is not going to look so much worse than the 60D one. In other words, you can just shoot with FF and crop when needed with little loss of IQ. But when you do not crop, you get much better IQ.
Title: Re: Major IQ advantage of FF?
Post by: AlanF on November 09, 2013, 12:21:26 AM
A FF camera has a larger area, BUT...
[...]
Has shallower depth of field (NOT always a good thing, ESPECIALLY with long lenses)

This is a misconception. FF does not have shallower DOF. It only has the option for less DOF when needed.

Sure it has shallower depth of field 50mm at f4 on a 7D is roughly equivalent to 30mm f2.5 on a 5D. Same framing, shallower depth of field. When shooting birds in flight, I need usually f8 on a 7D to get the bird at least mostly in focus. On full frame? That's f13. To maintain shutter speed, that means ever rising ISO's.

Yes. The Hi ISO advantage disappears.



And that is just plain BS you are talking. Assuming that you are taking a photograph of a bird with a 400mm lens 50 feet away. Let's see how the DOF works out at f/8 with the 5D3 and the 7D -

7D: Total DOF is 1.41 feet
5D3: Total DOF is 2.23 feet

I think that there are circles of confusion here! It seems pretty obvious that if you have the same lens it gives the same size image on crop and FF sensors, and if the two images are viewed at the same size on a screen or print they will have exactly the same depth of field. If they are not enlarged, but the FF is viewed at a smaller size, it will only appear to have a greater depth of field.

The arithmetic from the DOF calculator proves that the images have the same depth of field when viewed at the same size. The depth of field is calculated from the size of the circle of confusion. For the 5DIII it is 0.03 mm, for the 1.6x crop 7D it is 0.019. And 0.03/0.019 = 1.6. So, when you enlarge the FF image 1.6x to get the same size image as the crop, you exactly compensate for the difference in circles of confusion.

Similarly, look at the ratios of total DOF of the 5D3 to 7D. It equals 2.23/1.41 = 1.6. The image from FF has to be enlarged 1.6x to give the same size print as the crop, and in doing so you multiply the out of focus regions 1.6x and so reduce the depth of field 1.6x.

If talking in terms of equivalence, yes.

I am not sure that he is talking "plain BS". If you obtain the same field of view on the FF as on the 1.6x crop by either standing 1.6x closer with the FF or use a 1.6x longer lens, the crop has 1.6x greater DOF (calculated on the DOF calculator you used). If, as we have agreed, you crop the FF from the same distance with the same lens, 1.6x, then the cropped FF has the same DOF as the crop sensor.

Sure you can crop your picture and get the same DOF. But then you have turned your FF camera in to a crop body. The amount of sensor you use is the same on both. The difference then is that you have a FF body that you are using fewer pixels on the subject.

But who does this? The whole point is silly because who buys a FF camera with the intention of cropping the pictures down to crop body size.

You have entirely missed the point - it was an explanation of an aspect of depth of field that had arisen earlier. If you had read the earlier posts instead of jumping to (wrong) conclusions by reading just the last lines, you would have realised that. J.R., to whom I was writing, graciously accepted the argument. There is nothing "silly" about the point. The words "crap", "silly" and "BS" are bandied around too frequently, and often as a substitute for reasoned argument.
Title: Re: Major IQ advantage of FF?
Post by: takesome1 on November 09, 2013, 09:18:15 AM
A FF camera has a larger area, BUT...
[...]
Has shallower depth of field (NOT always a good thing, ESPECIALLY with long lenses)

This is a misconception. FF does not have shallower DOF. It only has the option for less DOF when needed.

Sure it has shallower depth of field 50mm at f4 on a 7D is roughly equivalent to 30mm f2.5 on a 5D. Same framing, shallower depth of field. When shooting birds in flight, I need usually f8 on a 7D to get the bird at least mostly in focus. On full frame? That's f13. To maintain shutter speed, that means ever rising ISO's.

Yes. The Hi ISO advantage disappears.



And that is just plain BS you are talking. Assuming that you are taking a photograph of a bird with a 400mm lens 50 feet away. Let's see how the DOF works out at f/8 with the 5D3 and the 7D -

7D: Total DOF is 1.41 feet
5D3: Total DOF is 2.23 feet

I think that there are circles of confusion here! It seems pretty obvious that if you have the same lens it gives the same size image on crop and FF sensors, and if the two images are viewed at the same size on a screen or print they will have exactly the same depth of field. If they are not enlarged, but the FF is viewed at a smaller size, it will only appear to have a greater depth of field.

The arithmetic from the DOF calculator proves that the images have the same depth of field when viewed at the same size. The depth of field is calculated from the size of the circle of confusion. For the 5DIII it is 0.03 mm, for the 1.6x crop 7D it is 0.019. And 0.03/0.019 = 1.6. So, when you enlarge the FF image 1.6x to get the same size image as the crop, you exactly compensate for the difference in circles of confusion.

Similarly, look at the ratios of total DOF of the 5D3 to 7D. It equals 2.23/1.41 = 1.6. The image from FF has to be enlarged 1.6x to give the same size print as the crop, and in doing so you multiply the out of focus regions 1.6x and so reduce the depth of field 1.6x.

If talking in terms of equivalence, yes.

I am not sure that he is talking "plain BS". If you obtain the same field of view on the FF as on the 1.6x crop by either standing 1.6x closer with the FF or use a 1.6x longer lens, the crop has 1.6x greater DOF (calculated on the DOF calculator you used). If, as we have agreed, you crop the FF from the same distance with the same lens, 1.6x, then the cropped FF has the same DOF as the crop sensor.

Sure you can crop your picture and get the same DOF. But then you have turned your FF camera in to a crop body. The amount of sensor you use is the same on both. The difference then is that you have a FF body that you are using fewer pixels on the subject.

But who does this? The whole point is silly because who buys a FF camera with the intention of cropping the pictures down to crop body size.

You have entirely missed the point - it was an explanation of an aspect of depth of field that had arisen earlier. If you had read the earlier posts instead of jumping to (wrong) conclusions by reading just the last lines, you would have realised that. J.R., to whom I was writing, graciously accepted the argument. There is nothing "silly" about the point. The words "crap", "silly" and "BS" are bandied around too frequently, and often as a substitute for reasoned argument.

I did read the earlier posts, and the comment is more to JR than anyone. You jumped to (wrong) conclusions yourself.
It is pointless to the OP's comments and this thread to say that you can use the portion of your sensor that is the same size as a crop sensor and you get the same DOF. In general people use all of the crop sensor when the are using crop bodies and they use all of the FF sensor when they are using FF cameras. In some situations they have to crop and this is true with both bodies.

And yes it is "silly" to provide an explanation of how your FF body would perform if you only used a crop sized sensor inside of it. Basically that was the description.