Coating a mirror
Hello. I inherited a home made stargazer/skygazer? Not really sure what its called. It has been in an attic without any protection since the late 60’s early 70’s or there about. I finally got some time on my hands and decided it is time to clean and possibly rebuild it. I know it works somewhat because i have been able to see the moon trough it altho a bit foggy and with a lot of small light dots in it. Reason for that is that the mirror is losing its coating. Now i live in sweden an have absolutely no clue what to look for since i have never worked with this kind of project. So is there anyone from sweden here that know how or where i can coat the mirror? Many thanks.
Posted Feb 4, 2023, 10:12 AM UTC
217
Here in Finland one optics company used to alumize mirrors, but they stopped doing that years ago with decrease of DIY telescopes.
Doesn't seem to be that many in whole Europe left doing that: https://stargazerslounge.com/topic/369752-mirror-recoating-services-in-europe/
Though price might not be far from completely new mirror assumnig focal length is "standard".
Silver coating would be DIY doable, but it doesn't hold its reflectivity for long.
I think my mirror has the silver coating indeed. Its a bit oxidized and brown-ish. Bit of a bummer that there aren’t many companies. But i understand its a niche market.
You can also ask on r/atming or at your local stargazing club.
I'm currently doing some quotes because I'm making my own mirror. From what I have read MCM optics in France or ottiche zen in Italy are well known. Ottiche zen has price list on its website.
Before re-coating you need to check if it's a good mirror (right curve) or if it's better to replace it.
Price list of ZEN (know to speak english) http://lnx.costruzioniottichezen.com/joomla/images/files_pdf/listino%202023.pdf
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The curve is good from what i understand from it. It was once a good mirror. Its just the reflective service thats damaged.. gonna do a bit of research but will probably end up looking for a half decent new mirror. Its an old hobby project and i am not a pro. It looks like an expensive hobby gehe
If the mirror is good, making it re-coated by a professional will be cheaper than a new mirror of equivalent quality. You find cheap mirrors on internet but they are not same quality. A good quality mirror is more expensive than a coating.
What is mirror diameter ? Under 150mm Is not worth it and it's better getting a bigger scope.