Field Tested: the Canon 300mm f/2.8L IS II

[Roger Clark]

Hi Roger and thanks. When it comes to pixels size and pixels on the subject I am very confused. I thought that larger pixels were better for controlling noise. And when it comes to image quality it seems that you are saying that the 7D is great. If that is true than why has everyone been bitching about lack of image quality and noise with the 7D for years?

Yes, I am saying there is great performance with a 7D versus larger pixel cameras. People complained about noise because they were mixing two (or more) things that affect noise. For example, a comparison might be 500 mm on a 7D and 1DIV, same f/ratio, same ISO, same shutter speed. But the 7D image shows more detail. The proper comparison is to add a 1.4x TC on the 1DIV then the pixel size on the subject (e.g. bird) is almost the same as the 7D + 500 (no TC). Then shoot at the same lens diameter (not f/ratio) (e.g. shoot wide open) and at the same shutter speed. Then the 7D and 1DIV images will be almost the same: same detail, same noise. No advantage to larger pixels. Larger pixels at a given focal length simply trade less detail for less noise.

Pixel size is interchangeable with focal length. Increasing focal length by adding a TC or changing a camera to one with smaller pixels can produce the same result in image detail and noise. This is a paradigm shift for photographers but is a trade space done all the time in remote sensing instrument design (e.g. spacecraft and aircraft imaging systems).

The game is changing. What formerly could be done with a large pixel camera and 1.4x TC on a 500 mm f/4 lens can now be done with no TCs and a 300 mm f/2.8 lens. Choose the camera with the lens. it is all part of the system design.

Roger