Messages

31

EOS Bodies - For Stills / Re: Is Full Frame sharper than APS-C? My answer here

« on: January 24, 2013, 03:29:57 PM »

Nah, the differences cut against the WA shot.

Seriously?

There is no way to quantify and compensate for the many variables which are different. Your test, however much you think it proves the point, is simply invalid.

As for your argument about the lenses, it's pointless because the crop-n-scale trumps everything else. Even the f-stop selection in this case. You didn't have any where near as many pixels on target, and then you let a computer algorithm (which one? what settings?) fill in the missing data. This bears no analogy or relevance to having an actual APS-C sensor, of the same MP resolution, take the shot with the same lens and aperture positioned for the same FoV. (Side note: the soft filter argument was silly. That does not come into play on that lens unless you select it.)

Again, I agree in principle because the principles are well established and understood. But the test you posted was horribly flawed.

If you don't think that this test demonstrated the importance of format size over pixel dimensions...well...all sorts of unflattering adjectives come to mind, with "hopeless" being the one best suited for a family-friendly forum.

Nobody can tell what your test demonstrated because of all the confounding variables.

I've compared FF and APS-C a number of times...all other factors being equal...and I've always found the same thing: FF is sharper out of camera, but the range is small enough to be closed by bumping up sharpening in camera or post. When the sensors are otherwise comparable of course.

32

EOS Bodies - For Stills / Re: Is Full Frame sharper than APS-C? My answer here

« on: January 23, 2013, 07:49:05 PM »

The simple version is that, even if the number of megapickles is exactly the same, the larger format will intrinsically produce sharper images.

All other things being equal, and assuming glass that does not have serious problems at the edges which are trimmed by APS-C...yes.

It's a simple enough experiment that anybody can perform: set up a still life. Take two images, one with a long lens and the other with a wide lens -- or with a zoom at either end of its range. Crop the wide image to the same field of view as the telephoto image, and scale the two to the same pixel dimensions.

While I agree with the principle, this test does not demonstrate it. The differences are way too large to be reliable (different lenses; scaling algorithms).

And, you can clearly see: the image generated with the larger, 135 format sensor is significantly sharper than the image generated with the smaller, P&S-sized sensor. And, again, I stacked the deck against the larger format in every reasonable way I could.

Nah, the differences cut against the WA shot. Again, I agree in principle, but this test isn't the way you demonstrate it.

33

EOS Bodies - For Stills / Re: Is Full Frame sharper than APS-C? My answer here

« on: January 23, 2013, 03:59:34 PM »

Some poster throw in "post production", that is not a valid arguement either.

The discussion is merely academic apart from post production. Nobody publishes images without post work, or at the very least non-neutral camera settings.

1. For the same pixel count on both formats, both can be as sharp as each other,  assuming that the lens can out resolve both sensor in the imaging area. That will put a lot of stress on the lens for APS-C sensor. The lens need 1.6 time reolving power compare to the FF.

This is false. Resolution is not a single number. It's a graphed MTF curve of contrast achieved at ascending resolutions as recorded on the sensor/film. The higher the resolution, the lower the detail contrast or sharpness.

If you have a FF and APS-C sensor with equal pixel counts, and all other factors are equal (lens, scene, etc), then the APS-C sensor will produce an image that is less sharp than the FF sensor. Within its cropped area, it's recording at a higher resolution than the FF sensor, and the lens will deliver less contrast at that higher resolution.

2. There are isolated incident that the APS-C can actually sharper than the FF if the lens use for FF have a severe problem in curvature of field or severe unsharp conrners. Since APS-C snesor only using the center part of the FOV of the lens. These problem may not exist. Therefore the APS-C is actually sharper.

Yes, there are some lenses where this is the case.

3. FF will be sharper if the lens cannot out resolve the APS-C sensor but it will out resolve  the FF.

Sort of. Again, resolution is not a hard number. It would be more accurate to say that FF will be sharper than expected (see point 1) if the lens MTF curve favors lower resolutions, i.e. if it really drops towards the bottom of the chart in the region where the APS-C sensor sits.

It should also be noted that contrary to popular belief the vast majority of lenses can out resolve current DSLR pixel pitches at MTF10. You would almost need a coke bottle to fail to do so. If you want to see lens challenging pixel pitches you have to look at compact cameras.

4. There is no doubt that FF will have better picture quality than thre APS-C, due to less noise, better DR.

Way too broad of a statement. There are actually people who will take this to mean that a 1Ds (original) will have better IQ then a 60D or 7D. It won't. Technology is at least as important as sensor surface area (noise) and pixel size (DR). Further, at this stage of technology, there are ISOs where noise is simply a non issue between the two formats.

6. In print, most of the difference will not be obvious due to the printing process.

I would say it's more due to scaling, but agreed.

7. How many people can tell the difference in music between  amplifier with 0.01% distotion and amplifier with 0.005 % distortion??

In a double blind study I would be surprised if anyone could.

34

EOS Bodies / Re: Yet Another 5D vs 7D Question

« on: January 22, 2013, 05:18:32 PM »

Just received a new 5D iii replacing my 5D ii, I also own a 7D. I love birding and will be receiving a 500 mm 4.0 ii supertele in June. With the 1.6 crop factor and a 1.4x iii extender, the effective reach on the 7D is 1,120mm. (can't use the 2x because of 5.6 f stop limit) With the firmware update on the 5D3 this spring I will be able to use my 2x converter on my 5D giving me a reach of 1,000 mm.

Here is the question: How will the quality of the pic on the 5D compare to the 7D. You will have a small crop on the 5D to reach an apples to apples comparison with the 7D pic.

When the crop factor is 1.6x the 7D does record more detail, but this only becomes apparent with really big prints. This becomes very clear with really big prints and cropping >1.6x. But admittedly most people don't push that hard and never see the difference.

Your lens/teleconverter mix results in virtually no cropping of the 5D3 image at all. (10%?) At low ISO it will be a wash between the sensors after post work (USM and LCE). At high ISO the 5D3 is going to walk away. The 7D sensor has no reach advantage here.

That said, I cannot tell you how the lens/teleconverter combos will compare. 2x produces lower IQ than 1.4x, even with Canon's latest and greatest. And you lose a stop of light. That's not enough to negate the 5D3's high ISO advantage, but it might just negate the AF advantage in dim light.

Personally, I would run a quick test of the two combos. My hunch is that the 5D3/2x will win out: still better high ISO and AF, IQ the same at low ISO. But there's a big enough question mark, based on the teleconverters, that I would probably go ahead and test it to verify IQ and AF performance.

35

EOS Bodies - For Stills / Re: Is Full Frame sharper than APS-C? My answer here

« on: January 22, 2013, 09:11:32 AM »

Images talk much better than words when you are talking about photography. I decided to test it myself, and took my 60D, and 5D Mark II, and attached the same 35mm prime lens, and took the same shot. The 5D image of 5616 x 3744 I cropped to 1.6, which gave me 3510 x 2340. I then downsampled the 60D image to the same size, and took a 100% crop of both for screen.

So you threw away any detail resolved by the 60D but not by the cropped center of the 5D2. Why would you expect a different result then the one you got?

I'll be the first to say that with current bodies the crop reach advantage only comes into play if you're making large prints from files which are cropped even further than APS-C. It is there. I've got 9-10 MP, 16x20, 7D sports prints that would not have worked with the roughly 3 MP left over had I been shooting a 5D2. But if you're making 13x19's that aren't cropped any further, you'll never see a difference.

But that still doesn't excuse performing your test in a manner which purposely throws away any detail gain in the 60D file. Would you do that in real life? (Same question for the test which started this thread: would you produce prints with no sharpening? Or do you blindly apply equal sharpening to everything regardless of subject / lighting / lens / sensor / final application and view size?)

36

EOS Bodies - For Stills / Re: Is Full Frame sharper than APS-C? My answer here

« on: January 22, 2013, 09:00:38 AM »

If we were stuck with 35mm and APS-C film, you would have a point.

We're not. We have sharpening settings in camera, and multiple sharpening options in our RAW converters and image processors (PS, Lightroom, etc).

APS-C sensors take more sharpening. Since sharpening is not an unlimited good, it's possible to equalize the two at ISOs where noise is not emphasized by the greater degree of sharpening required for APS-C. This is true through about ISO 800.

For the same reasons small differences between lenses are simply not worth worrying about any more. In the film days lens sharpness and contrast were of paramount importance because you were typically stuck with the result. Now if two lenses are close, USM and local contrast enhancement can make up the difference.

Knowing how to optimize your images in post for a particular application/print size trumps many of the equipment differences people love to obsess about.

37

EOS Bodies - For Stills / Re: 6D weatherproofness, tested.

« on: January 13, 2013, 04:09:06 PM »

The only really sealed camera bodies are the 1d series, with everything else it's a gamble.

No, with every SLR camera body from every manufacturer it's a gamble. That includes the 1D's, the Nikon D-whatevers, the Olympus bodies, pro lenses of every model and manufacturer, all of it.

Nobody in the SLR market tests their bodies and lenses using international specs, which is why nobody publishes that their bodies and lenses confirm to XYZ spec or can handle X amount of water/weather for Y amount of time.

This irritates the heck out of me because the manufacturers want you to think their products can be used in rough weather, but they don't want to deal with the warranty or maintenance implications of this. It's dishonest.

The level of sealing and resistance can vary quite a bit between models with the same ad descriptions. The 5D2, 7D, 60D, 5D3, and 6D are all described as "sealed less than a 1D", and their seal diagrams look almost identical. You would think that whatever "less than a 1D" means, they would all be the same. But in practice reports have been very good for the 7D, good for the 60D, but bad for the 5D2 and now possibly the 6D. Can't say I've seen much of anything on the 5D3 yet. Going by user reports there are clear differences in sealing between them, but nobody can determine that from the ads.

Not only that, sealing can vary over the life of your camera. With most real water resistant equipment you have to inspect and replace seals periodically. Nobody ever talks about this with SLRs.

It's stupid really, and the photography press (or a good lawyer) needs to start pressuring manufacturers on this point.

38

Lenses / Re: Sigma 50 1.4 or canon 85 1.8

« on: December 22, 2012, 07:04:02 PM »

I like both, but I find myself using the Sigma much more often. The focal length just seems more useful on crop.

85mm will result in more blur, but quality of blur (bokeh) has to go to the Sigma by a hair. That lens really has unique and creamy bokeh.

Agreed that the 85 is a bit more consistent in AF.

39

Software & Accessories / Re: Stop Using Instagram

« on: December 18, 2012, 02:33:34 PM »

Read.
Understand.
Comprehend.
Then delete your photos.
Then delete your account.

Well, that's what I would do if I had ever used it.
But I urge you all to do the same (you can keep the photos on your own pc, fine, but just take them off the website).
If we let companies like this get away with massive copyright infringements like this, then more will be tempted to do the same. Send a message now, otherwise facebook and flickr will be next, then anything you've ever sent on gmail and yahoo, and after that Canon will claim all the photos you ever make on one of their cameras.

Not that I used it much...but the Instagram app is GONE. Thank you.

40

EOS Bodies - For Stills / Re: Crop vs FF for landscape photography

« on: December 15, 2012, 05:25:39 AM »

I think the main advantage of FF to APS-C in terms of landscape photography will be DR.  You might argue that it's achievable with HDR but still it's different.

I've never thought this was that big of a deal for landscape because the landscapes I shoot tend to either be in the range of both, or way outside the range of both. It's never a 1-2 stop difference. The sun and shadows come into a scene (i.e. sunset) and it's 6 or 8 stops more and I'm shooting HDR. That said, yes, FF sensors generally have greater DR, especially when you post process to dig into the shadows. If you feel that's significant, it's a definite tick in the FF column.

Also, according to some sites, DLA is also occurs in much narrower apertures in FF thus helping the photos become sharper (even @ the same comparable DOF).

Diffraction does not impact any format more than any other for a given FoV/DoF. There's no deep DoF advantage either way, though FF does enjoy a shallow DoF advantage. (I think shallow DoF is overblown, but it's clearly there.)

The real advantage here, if you can afford it, is T/S for FF. Tilt the lens and you can get insane DoF at optimum apertures. You can sort of use T/S on crop, but the flash housing gets in the way, and who wants to pay insane amounts of money for an ultra wide T/S focal length only to have it cropped.

41

EOS Bodies - For Stills / Re: Crop vs FF for landscape photography

« on: December 15, 2012, 05:15:35 AM »

* Zooming is necessary.  Cropping to match FoV negates the purpose of the test, and moving the camera changes the perspective of the image, i.e. the size relationships of various elements - kind of important to a picture.  What viable alternative would you suggest?

We are discussing whether or not there is an IQ difference between sensors of similar resolution but different physical size. All other factors must be equal in testing this, or perceived differences could be due to something other than the physical sensor size.

I will grant that in some situations those other factors may be practically relevant. For example, when the choices were the 5D and 20D there were no good options for UWA on crop. But in judging any of this we must first determine what, if any, sensor differences exist absent all other influences.

* I stated 'equivalent' - thinking that I meant 'identical' is a huge mistaken assumption.

No, it's not. http://www.merriam-webster.com/dictionary/equivalent. Note "equal in value".

I did not assume anything, you misspoke. Next time be more clear and precise in your test description.

* Did I have to mention that? Really? What do you think, that I said, "Sweetheart, the first image in each pair is from my new, top-of-the-line camera, my favorite camera in the world, the second is from the old piece of crap camera that I'm going to give to our 3 year old as a toy...now tell me which ones you like better, wink-wink, nudge-nudge?"  The fact that you even considered something like that, much less labeled it a mistake that I made, is actually pretty damn offensive.

I have to mention it because the simple fact that you presented the images was a mistake, no matter how sincerely you tried to minimize it.

In all fairness, you could say the same of my experiences. But I wouldn't get all huffy and puffy and act "offended" if someone pointed it out. I'll admit it. So let's do it the right way and see if the results change.

FWIW, I am a card-carrying 'strict scientist', PhD and a day job in the field

This means nothing at all. All that matters is how a test is performed, and not who performed it. As a "card-carrying 'strict scientist' PhD' you should know and live by this.

Given your evident bias and unsupported assumptions in calling out my 'mistakes' I don't see any point in pursuing this discussion further.

Translation: you can't prove your point with hard evidence, so you're taking your ball and going home.

What a classic and intriguing case of human bias and emotion in action, and from a "card-carrying 'strict scientist', PhD" no less. This is why I never automatically trust scientists even in their narrow fields of study, but treat their claims with the same critical eye as I would anyone else. No matter what is claimed in training or degrees (pieces of paper with ink), they are still human, and display all the classic flaws of human nature.

42

EOS Bodies - For Stills / Re: Crop vs FF for landscape photography

« on: December 12, 2012, 11:47:16 PM »

Who is 'they'?

Everyone who has ever tried. I've posted unlabeled crop pairs to photo.net and dpreview, and shown 24" print samples to people in a couple photo clubs. Another dpreview member did the same exact thing, online crops, only with Nikon equipment. The results were random in every instance. Nobody could reliably tell FF from crop when push came to shove, even people that insist that there is a huge, just huge IQ difference. There is not at ISOs where noise does not come into play.

I always state that this is after processing. Crop takes more sharpening and more LCE. When you get close to the ISO where noise differences are clearly apparent, crop takes more NR as well. Make of that what you will. But I process all of my shots any way. If two sensors are close enough that differences are gone after processing, then they are equivalent for my purposes.

Now at higher ISOs it's not a contest. Crop is very good, but FF clearly has less noise with more detail. I should also note that if higher pixel densities were applied to FF then there would be a human observable IQ difference at any ISO, at least for large prints. Put another way, the D800 does produce large prints that are better than those from any crop body. But they're also better, by about the same amount, as those from any Canon FF.

Here's what I can tell you.  I took a series of paired, identically framed shots shots with the 7D and 1D X, using either the 24-105L or the 70-200/2.8L IS II, using the zoom to compensate for the effect sensor size on FoV (meaning same distance, so same framing and same perspective for each pair).  I shot about a dozen paired images like that, some landscapes, some architecture, and a couple of close-up flower/plant shots with the 24-105. I processed them equivalently, then showed the paired images to my wife, scaled down to 3.7 MP (full screen on an Apple Thunderbolt Display), and asked her which she liked better.  For 11 of the 12 shots, she picked the 1D X image.

Your three mistakes are as follows:

* Zooming the lens. This is likely inconsequential with these lenses, but it is a mistake none the less.

* Equivalent processing. This is a huge mistake which invalidates your test and your results out right. You do not use identical processing with different sensors, even different sensors of the same format.

* You do not mention if the shots were unlabeled. If your wife knew which came from which before picking, the results are less than worthless, they are misleading. There is no shortage of examples of conscious and subconscious human bias, of people picking what they think they should pick. It's just what we do. Even if they were unlabeled, a strict scientist would discount your results because you knew, and there's no shortage of ways you could have consciously or subconsciously telegraphed the "correct" choice to her.

That said, if you want to post a zip archive some where with the RAWs I would love to process them optimally and run a taste test at a site/time we agree upon. I'll record all processing steps for your review, and we can play with those if you feel they are less than optimal. I doubt you made any shooting mistakes that invalidate the comparison.

Side rant: One of my pet peeves with photography is that people make mountains out of molehills. FF vs. crop, Canon vs. Nikon, lens A vs. lens B, tripod A vs. tripod B, etc. They used to do it with film A vs. film B, developer A vs. developer B, etc. During the film/digital transition it was film vs. digital all the time. I've seen people argue that there are huge, just huge differences between PS scaling in one step or multiple steps.

Most of what we debate is meaningless. It is below the threshold of human observability even in a large print (or on a modern LCD), especially in the age of digital processing. But people absolutely cling to these debates. If you think there's a real IQ difference between two pieces of equipment or two techniques, produce some big prints with both. Go to a mall. Ask people who pass by if the photos are identical or different, and if different, which is better. You will quickly learn if the difference is meaningful or not.

43

EOS Bodies - For Stills / Re: Crop vs FF for landscape photography

« on: December 12, 2012, 08:18:01 PM »

So I was wondering, if higher pixel density is useful for landscape photos, would the 7D be a more useful tool for the job than say the 5Ds or 6D.

Higher pixel density is not more useful for landscape photos because you are typically not telephoto limited. You can use telephotos for landscape shots, but you typically end up using wide angle, ultra wide angle, and shorter telephoto lengths when you do use them. Higher pixel density comes into play when you need more reach then you can achieve with your longest telephoto, which is typically sports and wildlife.

On the flip side, contrary to the many claims you will hear, right now in the Canon lineup a 36x24 sensor is also not more useful for landscape photography UNLESS you own and use the T/S wide angle lenses. You will hear all day long how FF offers better image quality at low ISO. It does not, and you can demonstrate this all day long by presenting unlabeled large prints from both (or pixel crops online) and watch while FF fans stumble trying to guess which is which. They never can.

The Nikon D800 is the only DSLR which currently blends a FF sensor with crop sensor like pixel density for 36 MP, and that is useful for landscape photography if you are making large prints.

Another note: diffraction does not impact any format more than another for the same FoV/DoF. So there's no real deep DoF advantage for crop.

What does all this mean? Buy your crop lens if you want it. Don't worry about FF for landscapes until Canon produces a high resolution FF. (Or until you can afford $2k T/S lenses.) Even if you do decide to go FF, you can sell the lens for not much less than you paid for it.

Oh yeah: take a long, hard took at the Tokina 11-16 f/2.8. It has the optical IQ of the Canon 16-35 f/2.8L II.

44

EOS Bodies - For Stills / Re: Anybody upgrade from a 7D to 6D? What are your thoughts?

« on: December 10, 2012, 11:30:53 PM »

Ok...how about now, with the original full images downsized?  I know that I can certainly tell them apart, even at 800x533.

I can't tell them apart after using Noise Ninja with the 7D ISO 3200 profile. I imagine with proper processing this would hold true at 8x10 and 11x14. Past that you would start to see a difference.

I'll be the first to say that FF is better at high ISO, and that is a valid reason to go FF if you need high ISO. But like everything in photography, differences are exaggerated and blown out of proportion. Are you making 16x20 ISO 6400 prints? By all means, FF. Are you making 8x10 ISO 3200 prints? Use DPP (better noise handling at high ISO than ACR; at lower ISOs use ACR), Noise Ninja or another plugin, and put your money towards something that will actually yield a tangible benefit.

I don't know which category Helevitia fits into.

45

Software & Accessories / Re: Yet another tripod thread...

« on: December 07, 2012, 06:28:25 AM »

IMHO people tend to overestimate what's required in a tripod.

My first tripod was a $70 Ritz camera house brand (Quantaray). I was on a tight budget at the time. The thing was solid as a rock and produced steady day, night, and star trail shots for years.

The leg locks started getting sticky from too much use at the beach so I end up replacing it with another Quantaray tripod, this time about $90. Again, steady as a rock.

Granted these two tripods had thicker legs and more weight than the other small / thin leg tripods from Ritz or Best Buy or whatever. But I certainly didn't have to spend $200.

When I wanted something for hiking, I got Adorama's FlashPoint 1128 carbon fiber legs plus F1 ball head. This holds everything I've got steady, even for star trails to my surprise (it's a small/lightweight tripod, but is still tall), except for my 300 f/4L IS. And with that it's not so much that it's not steady, but I'm a bit worried about it being too top heavy.

Since then I've come to own a Gizo 1548 (gift from a good friend), a carbon fiber tripod that still goes for nearly $600 on eBay for just the legs. It is a tripod that can hold a super telephoto (i.e. 500mm, 600mm, 800mm) rock steady. The workmanship and materials are top notch and I can see why people spend this kind of money. I love it. BUT...in the end, if you have a more common body/lens combo, and the wind isn't howling, the $70 Ritz brand tripod would hold a star trail just as well.

Now I can't speak to the one you're looking at. But the 5 star Amazon reviews tell me that it probably is not a wobbly pile of scrap metal, and should hold your equipment just fine assuming the wind isn't howling.

FYI, here's the Flashpoint leg set/head I've got for hiking: http://www.adorama.com/FPTPF11281N.html

BTW, the one review noted that a leg "came apart." It's supposed to for cleaning and maintenance. If you're in a hurry and not paying attention you could over twist a leg lock so that it disassembles. I suppose this could be considered a negative. I consider it a positive when I get home from the beach having shot in sand and salt water and need to thoroughly clean the legs.