Help needed purchasing 2ndry Mirror

[mathewb]

Hi all,

I have managed to acquire a 4inch newt, but the secondary mirror on inspection is well ... not in good shape (there is no mirror surface left!). It looks like the silver has blackened completely.

I was wondering how easy it is to re-collimate a scope once you've played with the secondary mirror, and where the best place to buy one would be.

I live on the south coast and don't make it to Sydney too often, so an online store would probably be ok.

Kind regards,
Matt.

[dannat (Daniel)]

You'll need a small one, what is the current one size?
When I looked round 6 months matt from telescopes-astronomy in SA had some small ones for $34

[torana68 (Roger)]

first what brand is the 4" ?(pickie) reason being some are not worth the effort.
if its a reasonable one you could consider silvering yours at home or having it recoated
All else fails buy another 4" for a parts 'scope, re collimating is easy if you know how