dweller25

That scope NEEDS restoring - maybe Peter Drew could offer some guidance ?? My first scope was also an Astro Systems - a 1985 8.5” Newt

My Celestron C6 SCT almost matches the planetary views through my 4” Takahashi APO, the APO Views are just a little sharper with more contrast. The APO views are also more stable than in the SCT My 7” Intes Micro Maksutov gives overall slightly better planetary views than my 5” Takahashi APO but again the views are sharper and more stable in the APO In my opinion folded telescope designs can give very good results and offer excellent value for money, for me the shorter tube length is more enjoyable to use than with an APO Refractors do give a very sharp, tight view that is less affected by atmospheric instability than with a scope with a central obstruction

As an alternative to trying to cool it down you may want to wrap a couple of layers of silver thermal insulation around the OTA......

Yes a Dob for visual is all you need

I have decided to leave it as is. Performance is very close to a TSA102 Thanks for the responses

For the planets I am a refractor/Mak fan but the scope that gave me the best planetary views was a Skywatcher 250P. Sadly my back did not get on well with it, so I have changed my scopes so I can view from the rear. Newtonians give amazing performance and are excellent value for money.

Good idea Andy - I actually do this when collimating, but it does not help the front view problem. The good news with this scope is that it has ZERO image shift which is nice.

Aaah thats more like it - yes your scope looks to have concentric circles - as it should have.

Hello Andy. I don't think new SCT's have the orientation marks on the corrector now so I guess they are not matched. The corrector was bought new and is as it left the factory. Thanks for the manual offer but I think at some point I will measure to see if the secondary is central or not.

Sadly - No

Thanks knobby, I think you are too close, perhaps you could try another one at approx 2mts (your focal length) ?? I pulled back until the edge of the secondary was right next to the edge of the primary - approx 1.5mts for the C6

I might have to do that but would like to improve alignment if I can. The camera image is central to the OTA - I get the same view visually How does your C8 look from the front ?

Hello Peter, You are right, I can get all the reflections to line up perfectly by tweaking the collimation screws - but then the star test is poor and visually it does not perform as well ! Something is off center - but I don’t know what - does the photo give any clues ?

Hello, I am looking for some advice, here is a photo of my C6... The "hall of mirrors" photo shows something is out of alignment - However this scope has been perfectly collimated on an in focus star at x300, with perfectly symmetrical airy rings both sides of focus ! As a double check the views of Jupiter are very close to those of my TSA102 so the C6 even with this anomaly is working quite well I'm assuming the optics are not quite lined up right and even though I'm getting good results it would be great to know that I am getting the last bit of performance out of the scope with the best optical alignment possible. If anyone has any clues as to what to do to affect improvement I would appreciate your feedback.....

Congratulations Gerry on your new setup and first light. Those Taks are wonderful scopes that will last a lifetime