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View Full Version here: : Help needed purchasing 2ndry Mirror


mathewb
25-01-2015, 06:23 PM
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
25-01-2015, 07:17 PM
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
25-01-2015, 07:18 PM
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 :)