Glass path corrector for bino-viewer attachment
Bino-viewers need a certain optical path length. With many telescopes, such as Newtonians and fast refractors, there is insufficient focuser travel for them. The focuser hits the inner stop before the object comes into focus.
Glass path correctors solve this problem
A combination of lenses moves the focal plane further out, thus enabling almost the entire optical pathway required by the bino-viewers. Straight-view bino-viewers, such as the Baader wide-field bino-viewers, the BW bino-viewers, the TS bino-viewers, etc. can be used on any telescope. The lengthening factor is approximately 2.3 times.
Our expert comment:
This lens can be screwed into the filter thread of 1.25 inch eyepieces as a Barlow. It extends by a factor of 2.