Semi-DIY 0.965-1.25" Hybrid Diagonal

[Rocket_the_Raccoon]

Many people, including me, found out their telescopes cannot reach infinity focus (even with the focuser being fully retracted) after they purchased a hybrid diagonal in order to use 1.25" eyepieces. Most of the times, it is because the optical path (between the eyepiece field-lens and the focuser) being lengthened by the mechanical designs of both the 1.25" eyepiece and the hybrid diagonal. Without a feasible option of returning the item, I did some modifications to shorten the optical path. 

I used the top portion of a DWV plumbing 1 1/4" female trap adapter for the 1.25" end. The white plastic ring (a part of the adapter) is slightly elastic and does the job of securely holding the eyepiece. The .965" end, on the other hand, is made with the barrel of an old .965" H12.5mm eyepiece, the front cap of a 5x24mm finder, and some rubber. The whole setup shortens the optical path from the eyepiece field-lens to the focuser for ~10mm.

P.S. As every OTA is designed differently, even for objectives with the same specification, there is no guarantee that this modification will always work.

Edited May 18, 2017 by Rocket_the_Raccoon