Curiosity killed the CAT?

[Camelopardalis (Dunk)]

After a bit of reading around, I'd become convinced that all C6 otas have removable secondaries making them suitable for Hyperstar imaging. So I set out to investigate on my little faithful scope and attempted to unscrew the secondary...only problem being the complete secondary unit started rotating, including the baffle on the inside of the corrector

Anyone else had this before and know whether the rotational position of the secondary is important for image correctness? If so, any suggestions on how to re-align it?

Of course, as soon as I'd done it, a peek outside revealed cloud which later turned into rain, so I couldn't step out and take a look for anything obvious

[casstony]

There has been recent speculation that the secondaries are no longer retouched because Celestron has improved production techniques, making rotational alignment of the secondary unimportant. Perhaps an email to Celestron is in order to discover the truth of the matter.

[Camelopardalis (Dunk)]

Thanks Tony, interesting speculation! I'll drop them a line and see what they say.

[rodmollise (Rod)]

Most C6 OTAs have a secondary mount with a serial number on it. Rotate the secondary holder till the serial number is upright with respect to the fork (or dovetail) and you will be alright.

[Camelopardalis (Dunk)]

Thanks Uncle Rod, the serial number reads horizontally from left to right looking at the corrector (as if to look down the ota) with the dovetail on the left - the ota is orange from a Nexstar 6SE. The secondary holder stops at that point and won't rotate further clockwise, but will loosen up if turned the other way.

I did receive a response from Celestron support which confused me as much as anything else. The serial number may or may not be present, depending on model, etc. They suggested removing the secondary and the corrector plate and looking for the aligning marks to put it all back together correctly. If I could figure out how to actually get the secondary out that'd be a bonus

[renormalised (Carl)]

The SE series are not hyperstar compatible, except for the 8" model. The rest you have to buy the adapter from Starizona.

[Camelopardalis (Dunk)]

Starizona's parts was one of the things that led me to try to unscrew the secondary, as they sell...

• hyperstar for the fastar equipped C8
• a kit to convert an older/non-fastar C8 to be hyperstar ready
• hyperstar for C6
• BUT no conversion kit for the C6

[renormalised (Carl)]

Some 6SE maybe fastar compatible (newer versions). You've probably got the "wonky" version.

You should never fool around with things like the secondary mirror assembly unless you know what you're doing. Which means finding out how to disassemble it beforehand

[Camelopardalis (Dunk)]

I've definitely got the wonky version now

If I have to take it apart it'll be a good learning experience