I have been getting terrible video quality from my D3100 with the kit 18-55mm lens. I use the 1080p vide @ 24 fps with a sandisk class 10 card. My pictures always look fine. My video is always grainy no matter what. Even at iso 100. Iso makes no difference. I usually use Manual mode for video. I usually use f/8 or so and a shutter speed of 1/60 of a second usually. I don't know where i'm going wrong. What could be causing the grain? I need this resolved because I am going away tomorrow and I want to shoot some good video. Please help.