Despite all the acrimony in this thread, there is some interesting stuff. I would not dispute that that a FF is better than an APS-C with a 1.6xshorter focal length lens so that the whole picture area has the same field of view. I am interested in photography at super telephoto distance where crop factor is thought to be important. So, I decided to do a rough and ready test of FF vs APS-C doing my favourite hobby, taking photos of birds with a 300mm f/2.8 II +2xTC III. Accordingly, I took my ancient 7D and my new 5DIII and did the Old Grey Heron Test (parodying http://en.wikipedia.org/wiki/The_Old_Grey_Whistle_Test
). The heron did his bit, stayed in one place long enough so I could switch bodies. The 7D was at iso 400 and the 5DIII at 640. Consistent with my other recent experience, the IQ of the 5DIII makes up for the crop factor loss of 1.5 fold as the two centre crops were quite similar. The 7D was noisier, as expected. I usually use it at iso 320 or less. At great length extremes, the 7D does have an advantage but otherwise the FF is just as good for bird photography with the same lenses, and the closer you get to the target, the better it should be. It will be interesting to see when the 7D II comes out with more modern technology if it can overtake the 5DIII in the telephoto range,
« Last Edit: January 27, 2013, 04:41:37 PM by AlanF »
5D III, 7D II, EOS-M, Powershot SX50, 300/2.8 II, 1.4xTC III, 2xTC III, 70-200/4 IS, 24-105, 15-85, 100-400 II, Sigma 10-20, EOS-M 18-55, f/2 22.