NexStar 6/8SE collimation?

[Baz6170]

Is it true that the NexStar 6 or 8SE scopes may need regular collimating? I have a 4SE at the moment and I've never had to collimate it, but I understand that this is probably because the 4SE is a Maksutov-Cassegrain, whereas the 6 and 8SE scopes are Schmidt-Cassegrains.

[Peter Drew]

Schmidt-Cassegrains need to be well collimated to give their best performance, however they are the easiest telescope to collimate as you have only the secondary to adjust.

[smudgeball]

Hi

Mine is not bad.

I use "Bobs Nobs" on my secondary

(although they are Marmite on SGL )

It keeps collimation ok.

But it does need very fine touches.

Not a place for a heavy handed technique

Neil

[OneEyedSam]

+1 for bobs knobs ... we use them on my friends 6se

[baggywrinkle]

Had my 6SE 4 months, no problems.....have a look at

[LukeSkywatcher]

Had my 6SE 4 months, no problems.....have a look at

Ive wondered how to collimate my SCT (if needed). Sorry i wondered now. It looks like an ultrasound for a scope. Think i'll put my trust in the simple star test.

[OneEyedSam]

wouldnt want to slip with that screwdriver and scratch the front lens, hence bobs knobs (other knobs do exist

[Baz6170]

Thanks for everyone's posts, collimating a SCT doesn't look too bad at all : )

[tom33pr]

...Think i'll put my trust in the simple star test.

Apart from the star test It's good to do a 'day-light' check too: http://www.robincasa...ges/collim.html (you can just use a simple collimation cap for it).

...just to make sure

[LukeSkywatcher]

Apart from the star test It's good to do a 'day-light' check too: http://www.robincasa...ges/collim.html (you can just use a simple collimation cap for it).

...just to make sure

A colli cap is all i use and my SCT is fine.

[gkec]

Apart from the star test It's good to do a 'day-light' check too: http://www.robincasa...ges/collim.html (you can just use a simple collimation cap for it).

...just to make sure

I will have another go at that. I found the problem was that it would be easy if they were handily coloured black and blue but they all appear silver and make your eyes go funny.

How do you use a "simple collimation cap". I used one for a Newtonian -- is it the same for a SCT? I'm assuming it is the eyepiece cap with a hole in the centre.

[E621Keith]

Is it true that the NexStar 6 or 8SE scopes may need regular collimating? ...

No it's not true. Modern Chinese made Celestron SCT had improved mechancis and keeps their collimation much better than older US made model. In the 3 years I owned the C6SE, I only needed to re-collimate it twice.

Doing it with a star near the Zenith is still the best method of collimating an SCT. The primary mirror can shift when the tube is lay horizontally, which means a SCT collimated in the horizontal position can become miscollimated when it's in use.

[GyCx]

This is a very good collimation page http://legault.perso.sfr.fr/collim.html