Anyone need to center-spot or clean their primary mirror?

[iceman]

Hey guys.

If any of you dob/newt owners are looking to centre-spot or clean their primary mirrors in the coming weeks, it would be great if you could take photos and document the process.

We need a "how-to" article on the site for these common tasks, so it would be nice if someone had the time and inclination to write one up!

Thanks!

[asimov]

Yep. I'll be spotting my 12.5" mirror next week I would say..I'll take a few pics & do a quick write-up.

[frogman]

i will be interested to see how its done
secondry as well ?

[asimov]

Well....I'd like to spot the secondary, but I'm not really game, so no....I dont reckon.

[Starkler]

Heres a few to get somebody started :)

I took these during my last mirror cleaning exercise.
No prizes for guessing which ones are the before and after pics :P

[iceman]

Sonuds good John, thanks!

Anthony, I don't see any reason why you would want to (or need to) spot your secondary!?? :shrug:

[asimov]

Hey Geoff.... What kind of centre spot is that? I know it's one of those hole reinforcement rings....but can I see some sort of pattern or something on the ring itself?

[asimov]

Mike....re: centre-spotting the diag. From what I've read, some people work out the off-set needed for the diag. & then spot it at that measurement....ie if a 2mm off-set is needed, put the mark on the mirror 2mm off-centre.

I wont be bothering to do this though. I think I can guess a 2mm off-set of the diagonal using me lil' peep-hole-do-hickey. :)

[Starkler]

Just me scribbling on it in hopes a pattern would make it more easily visible.
It didnt help.

[asimov]

:rofl: Oh, ok....thought it might have been a brand new collimation technique!