Well, as flattered as I am by Todd's comments, I would not consider myself a wizard. I just picked up enough from my ex-wife who is a pro photographer to be dangerous. The TNVC camera is a Nikon D300. For NV through the tube images, I use a Nikon Nikkor 50mm f/1.8D lens with the ITT PVS-14 DSLR adapter ring and a Calumet Photo 50/46mm Step Ring. The step ring size is dependent on the lens you have for the camera.
Photographing through NV is a lot of trial and error. You need to make sure the camera is set to manual focus and your ISO is set high. I tend to do 2000+ depending on the lighting conditions. The image that actually captures tends to be a bit darker than what you see through the camera viewfinder, so you have to compensate for it. Also, the focus can be tricky. You have to focus the camera lens and the goggle. I start out by focusing the goggle objective and work my back to the goggle diopter and then the camera lens. From there, I adjust the goggle objective again for fine detail. It's a bit of an art, since the image might look very focused in the viewfinder, but might be out of focus a bit in the actual image when you look at it on your computer. You will have to play around with it a bit.