Hey guys, I have a WO Flattener 4 which I am trying to use with my Vixen ED80.
My method for finding the correct spacing was to centre on a large open cluster, with some good stars in the corner of the image, and adjust the flattener, refocus until the best possible result was obtained.
No matter where I position it, I don't notice a difference on shape? Is my procedure wrong, or perhaps the flattener is not compatible with the scope
Erik