Hello. I would like to confirm the following in regards to "infinity": If I a m working with a 210mm (8.26"inch lens)and I stretch the bellows out to a length of 8.26" inches, is this infinity? I have it understood that when you stretch the bellows to the length of the lens (8.26") you open up by 1 stop. At what po int with any LF lens do you have to start compensating for exposure? Thanks for any feedback...Bernard