Art No. : FF113-35mm extension tube 2”
With brass compression ring; Threaded for standard 2" filters; Total length = 70mm, Extension provided is 35mm (1.38").
GSO 2" Photography extension tube 35MM 50MM 80MM for astronomical telescope.
Different telescopes can have very different back focus distances.
In most telescopes the focal plane is deliberately moved further out, allowing users to attach cameras and other accessories more easily.
Refractors always have a rather long back focus since they are usually used with a star diagonal or erecting prism.
This high-quality GSO extension tube can be inserted into any 2" telescope focuser to gain an additional 35mm, 50mm or 80mm of back-focus travel. With this, eyepieces and accessories that you may not have been able to use because your fast telescope tube was optimized for various accessories use.