No, what the Canon community here on CR (and, I would argue, the photographic community at large given how many 5D III's have sold) is saying is that IQ is not solely the domain of the image sensor. There are other aspects of IQ as well. The AF system is indeed a very significant factor that assists photographers in maximizing IQ. The increase in frame rate is another significant factor in maximizing IQ.
I'd like to know how a higher frame rate delivers better pictures. What it really delivers is pictures faster but if you know something I don't, please go ahead...
A high fps also introduces more shake into the camera body because the slap of that mirror against the camera body transfers momentum from the mirror to the camera.
A higher frame rate delivers a greater chance that you will get better pictures. A better picture is not simply one that is more sharp, either. It is also the one captured at the right moment in time...where the subject has exactly the right pose, is not blinking, is looking at the camera, etc. etc. Sharpness is key, but it is not the only key factor in getting a "better photo".
The best sensor in the world doesn't matter a wit if its AF system and frame rate are low enough such that you can't actually capture the one frame where everything is still and sharp...a soft frame is a soft frame, regardless of whether the sensor pumps out beautifully soft pixels or not.
Again, frame rate does not correlate with sharpness. Just look at the 1D3. 10fps that delivered less than 50% usable pictures due to AF quirkiness. Boy was that a dog of a camera for sports photographers.
A high frame rate can
correlate with sharpness, when a subject is periodically moving and you want a frame where it is not. In the case of bird photography specifically, birds have periods of fast action, interleaved with moments of stillness. You need at least 6fps, better 8-10fps, such that in any burst of frames you get one where the subject is perfectly still. Even at high shutter speeds like 1/1250th or 1/1600th and a perfectly stable camera, the fast motion of a bird can still cause blurring. The 5D III is certainly better
in this regard than its predecessor. Obviously there are even better options, but that does not invalidate the fact that the 5D III is better than its predecessor, by 54%.
The issues with the 1D III are not extant in the 5D III. Blaming the 5D III for the problems of an unrelated predecessor is another copout.
I'd offer that there are far more photographers who shoot high action in one form or another who use ISO settings 800 and above than photographers who shoot still scenes or low action and use ISO settings 400 and below. To the greater majority of photographers, the AF system and frame rate are critical factors to attaining the IQ they require. To that end, I'd say Canon did well by their customers, and clearly listened to what their customers were asking for...less megapixels, higher ISO, less noise at higher ISO (hell, even I asked for that!!! )
If I was a professional sports shooter, I wouldn't be using the 5DIII - except for those post match shots of presentations, etc, where a flash is often used.
Sure, if you were a professional sports shooter. But there are also wildlife shooters. Bird photographers. Arial photographers (some who use the 1D line, some who were using the 7D line but have been all too happy to move to the 5D III). Sports is not the only source of high speed action. I chose my terms carefully.
The 5D III, as a general purpose camera, is ideal in an extremely broad set of circumstances. The 1D X is obviously the better choice for the highest speed action, but the 5D III does the job extremely well well when money is an issue.
Perhaps your finger-pressing ability is not that fine, however our minds can indeed sense minute differences. Our ability to measure time perceptually is not limited to 1-second increments, and even if we cannot send an impulse from our brains to our fingers in 1/20th of a second, that does not mean we cannot sense the difference between 1/10th and 1/20th of a second. Especially in the context of a camera shutter...looking through the viewfinder, it is very easy to recognize a TWO-FOLD difference in shutter performance, especially when holding the shutter button down and watching frame after frame race past at nearly double the speed. I'll say that again...a TWO FOLD, FACTOR OF TWO, 100% or DOUBLE the difference in shutter speed...relatively speaking, that is a huge difference!
You're mixing two very different things up in the one paragraph as if they were the same. And the way you're screaming about 6fps is similar to the way people screamed about more megapixels in days gone by. *yawn*
Emphasising, not screaming.
But I do understand the misunderstanding. The internet, a woefully inadequate communication mechanism. That said, I wasn't over-emphasising 6fps. I was actually directly addressing the naivete of your use of finger-pressing ability to the minds ability to detect sub-second differences in the timing of something. It doesn't matter if the difference is 3fps to 6fps, or 8fps to 12fps...the differences there from a relative standpoint
are quite noticeable.
But again, taking more pictures every second has nothing to do with IQ. Really, it just determines how quickly our SF/SD/HDD fills up.
Again, your missing the point. The notion that IQ is purely dependent upon the sensor is a fallacy. Getting a quality image means getting the little aspects of each key thing within the image correct. And that means all
of the little aspects correct...not just exposure, not just sharpness, but composition, subject position, pose, head angle, and eye contact. More frames per second, larger frame buffer, better AF system, etc. all lead to better IQ. The sensor is certainly the most important factor in getting each and every individual pixel that is recorded perfect, but if you don't record the right thing...well, it doesn't matter how good your pixels are. The wrong frame is the wrong frame. Bad focus is bad focus. The best pixels in the world won't give you enough post-process editing latitude to fix those issues.
In the last 3 years of shooting every week, I've needed/wanted more than 3 fps exactly once.
Well, that is you. And FOR YOU, if you don't need more than 3fps, it sounds like the 5D II is perfect! But, that's just you. There are other people in the world besides you.
Except that for the price the IQ is very very ordinary.
What exactly is "ordinary IQ"? I think your generalizing a bit too much...
The 5DII/5DIII IQ is now no longer anything special as it was when the 5DII debuted. It is now back in the pack and even various APS-C sensors out-do it.
It really depends on whether APS-C sensors out-do it. If you can get the same number of frames in focus, capture enough frames to get "the right frame", and do so with the same low level of photon noise at high ISO as the 5D III...then sure, the 5D III is "only as good as some potentially existent APS-C cameras". But, you still have to factor in the ability of the 5D III to get more shots in focus, and capture more frames in any given burst such that you get the one with your subject (which may be human, animal, bird, etc.) properly composed, in a proper pose or orientation, with the proper expression and eye contact, etc. etc.
My 7D is a pretty great camera. It has a high frame rate, a good AF system that does a great job, but can bail out and get sketchy at any moment. With quality L-series glass it pounds out the sharp like you wouldn't believe. But...the 5D III, despite its SLOWER frame rate, still out-does it because of the better AF system. The larger pixels on the 5D III result in much better noise characteristics, allowing usable ISO to jump from around ISO 1600-2500 on the 7D to as high as 12800 on the 5D III, while concurrently making ISO 1600 WORLDS BETTER.
IQ is dependent upon multiple factors. Sensor is only one of many. As I said previously (not sure which thread, maybe this one), if one were to rank the most important factors in IQ, I'd say the best rankings would be: Sensor is #3. Frame rate is #2. AF system is #1! Sensor only matters if the other two factors do their job, *lock focus*
and capture the *right*