Quote Originally Posted by HDNitehawk


[View:http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=398&Camera=474&Sample=0&am p;FLI=4&API=2&LensComp=675&CameraComp= 474&SampleComp=0&FLIComp=3&APIComp=2]


At comparable focal lengths, I wouldn't really say the 17-55mm beats the 15-85mm at the same distance.



Ahhh, but that comparison doesn't really address the question. As I read it, the question was 'what happens if you take the 17-55mm @ 55mm, and crop the resulting images,' i.e. by a factor of ~1.6 (1.545, actually) to an AoV of 85mm. The answer is basically the same as the APS-C vs. FF issue, cropping will increase your noise and DoF. If taking an image with a shorter focal length and the cropping it was the best answer, no one would buy a supertele lens, they'd all just use a nifty-fifty and crop the heck out of the images, right?!? [:P]