SwingBopper wrote in post #7114769
He's not having buyer's remorse. His critics are having post-purchase rationalizations for themselves. He is absolutely correct about image quality being negligible for prints up to 16x20 inches. Over that and yes, I think you will start to see a difference. There are several threads here including one of mine that compare side-by-side identical setup shots between the 5D and 40d and other xxD bodies. If you are in doubt take a look at the pictures. Lots of people deny it but they never post side-by-side identical shots to prove their point. You are hard pressed to see the difference in IQ. Of course IQ is not the only factor in evaluating cameras. I like my 5d2 for 3 main reasons: 1. wide angle, 2. bokeh and 3. nice lcd that you can use to check focus. The OP is wise to sell the 5d2 and buy some glass for the 40D for his needs.
That's an old argument and, given a set of parameters and context, is certainly valid. In fact, we can stretch it and say that given the right lighting, framing, technique, type of photograph, and viewing size, me 4,5, and 6 MP compact cameras have produced images with image quality that rival any of my DSLRs.
So, in those parameters, it's all good, and is in fact a compelling reason whay many people are best served staying with P&S cameras, while relatively few are probably best served by moving from a crop DSLR to a full-frame DSLR. By the same token, relatively few 35mm format DSLR users are well-served by spending the big bucks to buy into a high resolution medium format digital back system. It's not that there are not real qualities and benefits to the medium format system, but the high price and to some the size makes it not the best choice.
So, the high resolution full-frame body has a similar payoff in quality over the crop camera. The one fundamental deciding factor is price vs performance. It's not, and can not, be that the crop is equal in quality to the equivalent to the same generation full frame sensor, simply that the crop gives great quality that within the same parameters rival the quality you may get from a full frame sensor, although it will not always give that if you stretch the parameters of your shooting and what you do with your images.
So, what's the big deal? For most people, not as much, which is why most DSLR users are best served with a crop body with all the features that make their shooting easy and the best it can be. It's really no big deal, except when people get argumentative or make statements that are rather far-fetched. Either side (users of either system) can do this, hence the rapid-fire debating that tends to go nowhere
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