View Full Version : Nikon AM 120 macro lens

15-Feb-2013, 14:28
what bellows dram would one need using a nikon 120mm AM macro lens with 4x5 film to get 2:1 macro?

Tom Monego
15-Feb-2013, 15:08
I believe 480mm would be 2:1, used to know this stuff.


Dan Fromm
15-Feb-2013, 15:16
The magic formula is: rear node to film distance = focal length * (magnification + 1).

The lens rear node is approximately at the diaphragm, so is a few mm in front of the board. Extension will be approximately 120 * (2 + 1) = 360 mm.

Walter Calahan
15-Feb-2013, 15:32
Damn if I own the lens but have never used it at 2:1 to know this detail. I do know to always measure from the nodal point, but all those formula learned in class decades ago have faded away. Grin. Good luck.

15-Feb-2013, 22:48