[TWiTCHY]

You''ll find that increasing the ISO makes your pictures grainy, and vice-versa - I think that's what the person was trying to get at, but if you don't have something stable for your camera to sit on, having a low ISO will result in blurry pictures. I'm not sure if the D40 has this setting, but on the D60 there is a "Noise Reduction" setting which removes a little of the grain.

Increasing your ISO will also allow you to shoot at a faster shutter speed, reducing blur but increasing noise simultaneously. Try it

After you get used to how your camera shoots under certain conditions, adjust the shutter speed and ISO together to get the least blurry and least grainy picture.

I'm wondering if the person who told you to leave the ISO as low as possible is talking about normal, well-lit, conditions, or under dim light?

[Dascamel]

D40x has the noise reduction. Just tried some high ISO shots in low light, they came out great. Keeping the camera stable was the toughest part. I tried a night shot focused on a star, at 1600 ISO was able to see others stars not visible with the naked eye. The entire sky lit up.

[MCS]

tips on shooting in low light:

1. Get the right lens - Buy a fixed 50MM F1.8 or 1.4 lens. This lens will work 4-8 times better at shooting in low light than the kit lenses that most cameras come with.

2. Set ISO higher to 400 or 800. Graininess should not come into play until higher than 1600.

3. Tripod the camera

4. If you really have the time, set the shutter speed longer - open the shutter for a longer time to get more light (Everything has to be perfectly still)

Good luck

[TWiTCHY]

Plus, get a wireless remote on top of a tripod. That way you don't have to risk shaking the camera while trying to release the shutter.