There was a discussion recently on a forum I visit about using your camera to scan film originals, because (good) scanners are not as available as they used to be. It all got very complicated and detailed, using medium format large sensor cameras and so forth. But it got me thinking and wondering how my Nikon D700 would perform.
I photographed two negatives, one a 6x4.5 black and white (which I had actually neglected to scan when I did have an Imacon high-end scanner) and a 35mm color neg. I used as my light source a light box (fluorescent tubes), which really you should not do because of the limited colour spectrum, and set the white balance to auto. The results were surprising, surprisingly good, that is. The B&W fared better, because, I suppose, of the larger sized original and no colour problems. Whereas the colour neg with it's orange mask was a mess once I inverted it to get a positive. It took a heck of a lot of meddling around in photoshop to get anything reasonable. But I'm left with the impression that if you had medium format transparencies in your archive that you wanted to have files of, it is not impossible to get reasonable quality by using your camera. (Just don't use a lightbox).
Here are the images: