Help choosing 7d, 550d or 50d?

[LongLensPhotography]

The 50D has better noise control than the 40D, considering the increase in megapixels, and you can safely use the higher ones which the 40D wimps out at.

So what is the magic recipe for 50D? I am really interested to know before I put it for sale, as mine doesn't get even close to 1DsII, and I reckon 40D also gave me cleaner output with more dynamic range.

I can understand how downsizing 15MP back to 10MP would help with luminance noise. I can't see how to get the dynamic range back. 40D allowed up to 2 stops highlight recovery at ISO100, there is only a stop with 50D. Shadows are more noisy, hence can't be pulled very far. The worst is ISO400 where I still expect very clean files but see some chroma noise instead! OK, 50D can print 8x10 just fine and amateurs do love the badly over-saturated and crisp screen. I am somewhat more concerned with IQ, and A3 is my most common print size at the moment. Clearly weak AF wasn't enough for Canon, they had to go further to force people to 5/1 series.

 

[simond11]

I use a 50d for motorsports and never had a problem with it. I use a 100-400 L and a 24-70 L and get great results.