I recently went from full-frame (film) to the 1.5 "cropped" sensor with an old Nikon D200 ('cause I'm cheap). I get all the image quality I need with the smaller sensor and only 10MP. (But if I want mind-blowing detail, it's easy to take 4 or 6 or 8 images and stitch them.) And the newer models you mentioned will be many years improved over mine. As others have said, ergonomics and glass are the most important.
OUCH you do seem to be all over the place
are you a female with small hands perchance
I would go with Nikon equipment Camera AND lenses
I have just bought used a D700 AND a a whole host of really good (BUT not Pro)(a good Pro AF/AF-S Nikkor Zoom will cost around £1,000 or more - old manual ons are cheaper but hold their prices very very well) Nikon AF lenses - Nikkor 50mm 1.4g. Nikkor 85mm 1.8 Nikkor18-35mm 3.5 Nikkor 35-70 2.8 Nikkor 70- 300mm 4.5 and i am still well under £2,500 spend ATM
Just carried out a quick but fairly deep comparison with my sons Canon Rebel 550 with the kit zoom and unless you are going to print at 60" x 72" your not going to see any real differences in the end result Of course the D700 has an imense ISO range and it can poroduce results in light that the Canon cant even contemplate.
IF you have small hands i would go for a D40 really cheap and cheerful off flebay < £150 if you are a canny bidder OR if you want to use all the old 35mm manual AS-I Nikkor lenses from the manual film camera days and want in camera metering get a D200 prob have to pay around £350 on fleabay a D90 will cost around £600 on fleabay Old and great AS-I Nikkor lenses start from under £50 on fleabay
go here and have a LONG HARD READ
KenRockwell.com: Photography, Cameras and Taking Better Pictures
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