I am setting up some still lifes that will be about 1:1 very close up. When I meter the scene, should I meter from where the lens is, or where the film plane is? Normally, I wouldn't care, but shooting this close I am not sure. Also, is there some kind of calculator available online, that would let me punch in my lens focal length, what my bellows length is, and then tell me my additional exposure to add? Lastly, when measuring bellows length for something like this, would I measure from the diaphram opening of my shutter to the film plane, or the rear of the lens glass to film plane, or some other distance? Thanks for any comments.