ahhh okay. so for a 55mm lens in the case of a micro nikkor if i chose to go that way - i'd be looking at (10 +1)x55mm = 605mm

and in the case of an 80mm rodagon:

(10+1)x80mm= 880mm

wow that was easy cheesy.

Although what confuses me about that is - I always understood that ever doubling of a bellows length implied a doubling of image size (and quadrupling of exposure of course)... but in the case of a 55mm lens - 1:1 gives you 110mm and therefore 2:1 gives you 220mm 4:1 is 440mm etc... which doesn't seem to jive with the above formula!

which is wrong here? (not meaning to complicate things - I'm thankful for the formula though)