Q, from Tony: I was wondering if you have any advice as to whether the Vortex 2x Doubler will work with the Leupold Katmai 10x32 binoculars, as you carry both products?
A: Thanks for contacting Eagle Optics regarding the use of the Vortex Doubler with the 10x32 Leupold Katmai.
Although the doubler will fit snugly over the eyecup of the Katmai, it isn't advisable to use the doubler with your 32mm objctive lens binocular. Without the doubler, the exit pupil of your binocular is 3.2; with the doubler (since the magnification increases to 20) the exit pupil shrinks to 1.6. This provides an extremely dim view. You would also have to hold it a few inches from your eye in order to see the complete image. I worked with it and found it quite unsatisfying!