Hello, I'm hoping you might help me out here because after dismantling the bloody thing I am still at a loss!
I am rather new to stargazing, and still sticking to manual alt-az star hopping under city sky (so far), which was actually the motivation to add a planet to the moon viewing and move from (quite enjoyable) white light observing with the lunt wedge on my tv-60, to my first H Alpha scope. I went for the PST instead of the Lunt 40 because it looked like a simpler build, which now I have seen up close is actually way simpler even then i suspected :-D
Right out of the box, I noticed that the pst could only show some surface detail, a sunspot a n d tiny prominences at a single focus spot which was right at the (left) edge of the tube turn. Anywhere else to the right - nothing but a blank (but vibrant, which seemed to rule out rust issues) red disc. This looked odd because I was expecting to see either (prominence)-or(sunspots and granulation) but not all together, but there it was. I thought maybe the tube turret had been mounted wrong, so I took the rubber band off and moved the stopping screw five holes to the left. The result is that the focus spot is now at the middle of the tube turn instead of the extreme left, but nothing else seems changed. I still see a blank disc when turning the etalon right or left of that point.
A second issue regards imaging - I'm not set up for ccd imaging and like I said don't use a tracking mount, but merely handhold a digicam to the eyepiece, still unlike my afocal moon captures with other scopes, the images i took through the pst all show the same - the disc at an angle, with a big blank spot, and granulation at the top only. as for prominences, unlike naked eye observing, the digicam captures either the prominence, or the inside of the disc (without moving the etalon though), but maybe that's as it should be (?) attached two sample pics (the second is a stack of nine consecutive captures) . Do these seem normal to you in a pst?
Naturally suspecting filter rust i had a close look at the blocking filter and the itf, and found no edge or center rust on them however, both feature golden specks which I wonder about (phone pics attached!) - oxydation? something else?
Lastly, the prism doesn't look well aligned to me. I have tried to nudge it a little but it returns to its original place. However I didn't remove the screw (there is a big blob of glue round the contact area)- was that a prerequisite to successful adjusting of the chips? The misalignement isn't huge, but I wonder if it might be sufficient to produce that angled image I see in the eyepiece (?) - more phone pics of the prism attached
Edited by Daphne S, 16 October 2021 - 12:30 PM.