Removing the "Trash" from a Trash Scope (Part 2)

[Rocket_the_Raccoon]

            

About 4 months ago, I brought a $20 trash scope (50mm f/7) back to a usable state at minimal cost, it was posted here : https://stargazerslounge.com/topic/315129-removing-the-trash-from-a-trash-scope-trash-panda/. Recently, I made two "improvements" on it. First of all, I added a "screw eye" on the hood to align with the L-bracket on the tube to make the "finder" more accurate. The adjustment/alignment is done but rotating the hood and screw eye itself. Next, I replaced the 45-degree hybrid-diagonal, which I found to be extremely difficult to use for astronomy, with a .965" 90-degree mirror diagonal that I scavenged from a $5 toy telescope (single-element objective, a "real" toy). I then use the .965"-1.25" adapter that was included with the 50mm in order to use 1.25" eyepieces with a .965" diagonal. Note that both the .965" mirror diagonal and the .965"-1.25" adapter have a 20mm opening instead of a full 24.5mm. Thus, my TFOV will be limited to 3.18 degrees. Fortunately, my Celestron 20mm eyepiece has a field lens of the same diameter so no field is wasted.

The result, despite the mirror diagonal coming from a toy scope, is pretty good. No light-scattering is visible and the mirror seems to be well-aligned. Images are just as bright as the prism and of course, a 90-degree viewing angle is certainly more comfortable to use than the 45-degree one. Well, now I have an ultra portable carry-along or ever-ready-in-the-trunk scope.

   

[Paz]

Very nice, I like the finder set up!

[happy-kat]

That looks super portable.

Have you tried mounting the telescope like the below image. It crudely separates azimuth from altitude adjustment rather than rolling the ball head around.

[Rocket_the_Raccoon]

9 hours ago, happy-kat said:

Have you tried mounting the telescope like the below image. It crudely separates azimuth from altitude adjustment rather than rolling the ball head around. 

That's indeed a good idea. I should give it a try once the night sky clears up. Unfortunately, rainy season just started over here in south western Canada.