But last time the conversation was comparing a 10D with only 8 megapixels or w/e it has, which made sense. But cropping the inner APS-c FOV of a 6D wont giver you as big of a difference between the 60D right? As far as comparing a current APSC to a current full frame, that argument doesn't apply.
I mean if a crop and a FF shoot a 200mm shot, the crop would 'look' to have further reach, but that could be duplicated, could it not by 'cropping' the FF in post...and wouldn't you have a cleaner pic from doing that from the FF?
Answer to both of these is the same. From an IQ standpoint, there's not going to be a meaningful difference with contemporary sensors (for example, when I compared the 5DII cropped to the 7D, with no processing the 7D image was a little bit sharper and a little bit noisier...and some NR would reduce the noise and the sharpness as well). What you're giving up is megapixels...the cropped 5DII image is 8 MP, vs. 18 MP with the 7D. So the real question is, what image size do you need
, and that depends on what you'll do with the images. If you'll print 24x36" and hang on your wall, the 7D wins. If you'll print 8x12" for a coffee table book, there's no real difference...in which case, I'd pick the FF for the much better IQ when you don't need to crop, or can use a longer lens.
Keep in mind, also, that the above applies only when 'focal lentgh limited'. If you can use a longer lens, the FF wins, hands down. Back to the 7D vs. 5DII cropped comparison, I also compared the 7D + 85/1.2L II vs. the 5DII + 135/2L (basically the same framing and DoF at a given distance). The FF won, no contest...
Well, back to Rithmetic. If a FF camera has 16 MP then it's APS-C equivalent with the same size of pixels would be 16/1.6 = 10 MP.
You and Rithmetic.
You need to get better acquainted with each other. If a FF camera has 16 MP then it's APS-C equivalent with the same size of pixels would be 16/1.62
MP. Thus, a 6D's 20 MP image cropped to APS-C framing would yield a 7.8 MP image.