Grainy pictures

[canonbraden]

I was out taking some long exposure pictures of cars last night with my new 24-105mm lens. The pictures turned out really grainy and not sharp at all.
Any advice?

 

[Braineack]

post examples?

 

[Big Mike]

Yes, we need to see examples (along with the EXIF data).

Noise (graininess) tends to show up when you use high ISO. Especially if you underexpose the photo have have to make it brighter.
Noise can also be more prominent with long exposures, because of heat building up on the sensor.

As for sharpness...I assume you are using a tripod? Long shutter speeds will cause blur if either the camera or subject is moving...so it's practically a requirement that you use a tripod for long exposure shots.
Did you have IS (on the lens) set to on? It's not always common knowledge that you have to turn off IS when using a tripod, otherwise the IS system will actually cause the lens to shake and give you blur in the photo.

 

[canonbraden]

I will post some pictures when I am on the computer and can access them from there. (Currently on an iPod)

 

[gsgary]

Were they shot on film ? if not they are noisy