Posted by Les Newcomer on December 04, 2000 at 10:11:51:
In Reply to: 1:1 focusing with 127mm lens on super graphic posted by ken binner on December 03, 2000 at 20:16:31:
The easiest way to know it's 1:1 is to buy or make up a Calumet bellows factor finder. This is nothing more than a piece of white or black plastic 2" square and a flexible plastic scale that reads both reproduction rates and bellows factors.
A cheap version of this would be to substitute a 2" slide mount and a plastic ruler of your choice. When the object on the ground glass reads 2" Then it's 1:1. You can come close by putting the standard 254mm away from the ground glass and the object 254mm from the standard.