I got my Canon EOS 400D Combo (EFS 10-22 USM & EFS 17-85 IS USM) some months ago and it worked fine for everyday snaps. However, I do find its limitation when it goes to serious work during a wedding event that requires more accurate auto focusing capability and flash exposures under some low light indoor environment. I decided an upgrade and enhanced my combo for some serious work while maintening portability. Canon EOS 40D, Canon EOS 5D and Nikon D300 are in my list.
While 5D produced the best image quality in my eyes, its AF is not functioning as effective as 40D, it requires an external flash unit in order to assist on low light AF and provide filled light. The Nikon D300 is a more comparable choice, but it does cost $600 more on the body and I also need a Nikkor zoom lens (in addition to my prime collections) to meet the requirements for the exercise. After further investigation, 40D is the best choice in this situation, it works very well with my existing lenses 10-22 USM & 17-85 IS USM.
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Lastly, I tried to challenge the 40D’s higher iso performance, the effectiveness of the lens 17-85 IS and myself – point & shoot handheld ability. All sample shots below are straightly out of camera at iso3200, aperture locked at f/8, all others default, only resize and rotation applied by PS. There is some banding effects at this sensitivity level, but you could hardly find that at busy area, iso1600 and lower sensitivity levels.