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Bob Atkins , Oct 30, 2008; 02:15 p.m.
I'm currently looking at a 50D for review here on photo.net.
My initial findings are that it has a slighly higher resolution than the 50D and the noise level is slighly lower. Neither is a "night and day" or "knock you over the head" difference, but they are fairly easy to see if you look at the images at 100% on a monitor. Performace at ISO 12,800 suffers quite badly from the inevitable noise reduction techniques which are necessary at that speed, but it could still be useful at times. Just don't expect great 20x30 prints at 12,800!
My intital tests don't agree that high ISO performance is worse than the 40D. To me it looks slightly better, but that's only based on one series of test images and mostly on the in-camera JPEGs (which have had some default noise reduction applied to them). I haven't had time to do extensive noise comparisons yet, or have I had a chance to look in detail at RAW shots. I think the high ISO 50D JPEGs have more noise reduction applied to them than is the case with 40D high ISO JPEGs, so the improved noise in JPEGs (and RAW images converted in DPP with default paramater settings) may well be due to that.
As for ISO 12800 being useless (or "pointless"), I'm afraid that DRR are falling into the trap of looking at 100% views on their monitor screens. I've made 4x6 prints from ISO 12800 images that look quite nice. Very acceptable indeed. I don't know what they'd look like at 8x10 or 11x14, but I suspect that 8x10 wouldn't be awful.
When you add in the nicer LCD and features like microfocus adjustment (which should be a cure for all those "my lens is front/back focusing issues), I think it's a worthwhile upgrade to the 40D. If I had the cash I'd probably get a 50D over a 40D, but I'm not rushing out to dump my 40D for $700 (if I'm lucky) and pay $1400 for a new 50D.
I'd hope to have a review finished and published here on photo.net in maybe 7-10 days from now. My initial thoughs are that it's a very nice camera, and the expected overall incremental improvement over the 40D, not a quantum leap as people always wish for. Whether any increased noise is more than made up for with other features is question of course, but for most users I doubt that the noise will be a problem.
Again these are preliminary observations made on the basis of one series of test shots. It's possible that additional testing may modify my preliminary conclusions and looking at RAW shots with all possible noise reduction turned off may result in additional conclusions about intrinsic sensor performance.
