Secondary Mirror recoat (now a discussion about minimum secondary size)

[Jethro777 (Jethro)]

Thanks Mark and Jeff - I want to replace the secondary due to damage. When I do so, I don't want to get one that is too small, or too large. I've also adjusted the primary as per the recommendations the Russian users had on these first versions.

The travel is insufficient to get focus on modern eyepieces without the 28mm primary mirror adjustment.

As for its quality, they are exceptional. I love mine, and I certainly want to have a proper matching secondary. Does anyone know the strehl quality on the primary on these? I know it probably won't make a difference too much - but I'm emotionally attached to the thing!

>but there are other options too.

What do you mean Jeff? Tell me more.

[Saturnine (Jeff)]

Just meaning that there are other suppliers of secondary mirrors besides GSO but they probably need importing from the US or UK and are more expensive but supposedly better quality, especially Antares. Orion Optics smallest is 35mm which is getting a bit big as far as obstruction goes.

http://www.antaresoptics.com/
https://www.orionoptics.co.uk/OPTICS...icalflats.html

[Jethro777 (Jethro)]

I was actually thinking of the 1.3” Antares.
They don’t make a 1.1”.
I think a 1.3” probably would work well?