What lens do you currently own, and what will you be using the camera for?
Also – what accessories do you have – flash/syncing/bags/tripods/ etc?

Look into a canon 5D wonderful camera !

questions:

why do you want to go below ISO 200 or 100?
why do you want to go above 1000
is weight and/or size an issue
what can’t you do now that you want to do
what is awkward to do now and what would make it easier
what do you like about your current camera
what other cameras have you used, and what did you prefer about them

i want to go lower than 200 because sometimes a want to play with long exposure during the day i can not do it with my current camera. And after 500 Iso the sharpness is not good so for sunset times i have problems.

What i like a about my camera is easy to use, the manual format is user friendly lots of short cuts to changes setting : white balance, iso etc..

Before than the nikon d 70 i had a nikon 60 (film).

I’d suggest staying with Nikon if possible, simply because the controls will probably remain reasonably consistent with the ones you are used to and like.

You’re unlikely to find anything lower than 100 ISO on a digital camera, and the extra stop isn’t going to make that much difference. One solution to that problem is to buy some neutral density filters. Cheaper brands may change the white balance (being not accurately ‘neutral’) but this is no longer the problem it was with slide film! (Using two polarisers, crossed, can make a very dark filter!)

Sharpness shouldn’t be affected by ISO setting, so I wonder if you’ve got some noise removal being applied by the camera (if shooting jpeg) or processor (for raw)? Noise removal smooths things out a bit and can give the impression that the image is slightly less sharp.

I don’t use Nikon cameras, but the obvious upgrade path is the the D300. If you don’t want liveview the D200 may still be available fairly cheaply. (I was with some Nikon users last Autumn who were planning to upgrade to the D200 because the price then was good.)

Have a look at some review sites to compare the D70, D200 and D300 results – I’d suggest www.dpreview.com

And I’m going to disagree with Mark on one thing – you don’t necessarily need a flashgun – it depends on your style of photography. I’ve not bought a flashgun for my cameras since I switched from the old Canon FD mount to Minolta AF (probably 6 or 7 years ago) and very rarely use even the flashgun built into the cameras.

thank you to both of you for you time. i will search i let you know what i bought .
thank you again
ama