I recently purchased a proportional divider on-line (Prospek). It looks like a similar design as the AccuraSee that Kingston recommended, except mine has seven holes, all equally spaced out. The only ratio that works is the 1:1. The 1:3 on the other end is off, the larger the object the more the scale is incorrect. I have tried the center for 1:2. It is not a 1:2 ratio. I tried the holes next to it - even in centimeters just to see. No luck.
Am I wrong in my expectations of a proportional divider? Shouldn't there be a direct ratio?
I am supposing the AccuraSee would measure 6" if measuring 2" object on paper using a 1:3 scale.