I've been shooting for about a month now. (Canon XTi) I just can't seem to shoot in a room without the flash. I've tried the lowest F Stop and as low a shutter speed as I can go. What else should I do? Even if I set the camera on a tripod and do a .3 sec shutter, it's perfectly focused but it's all grainy. Any point and shoot film camera I've ever used always seems to work with the ambient lighting. Any advice will greatly be appreciated.