Not sure about the auto meter. If it is truly a 'body' meter that doesn't care which/if a lens is attached, it should work. I wouldn't really expect this to work on a modern DSLR since they are so dependent on communicating with the lens. I really only do this with manual bodies and lenses. I usually add a stop to what I read on my handheld meter or sunny 16 to compensate for "bellows extension". I also usually only do it if I can use f/4 or better. Trying to keep something in focus at f/2 or heaven forbid 1.4 is just too hard and I'm generally too lazy to lug a tripod around.