The best secondary mirror money can buy....

Where do you think it comes from?

(I'm in the process of selecting one for my 8" f/6).

-Jason

Antares make them up to 1/50 wave, really 1/30 is available but sometimes they have them above this as high as 1/50 wave. They have a 1/30 wave flat to set the Zygointerferometer, so they can measure very accurately.
I got a 1/30, 1/23, 1/20 and a 1/50 wave from them and I think that are all great.
Call and ask what is the best wave they have in your size.

Hi Jason,

For a long time I think the answer was just automatically "Protostar", but now Antares will quote them down to 0.020 PV, and Protstar only goes down to 0.045. Also it is interesting that Antares puts them on the interferometer after coating; I don't know if Protostar does the same. BUT you can get the Protostar made out of quartz. I don't know if that is meaningful with such a small surface, though.

(But how can Antares claim 0.02 PV when their interferometer is calibrated with an 0.033 PV flat?)

I have to make this same decision sometime soon too, but I'm not finished overanalyzing it yet . Prolly I'll go with Protostar so as to save a phone call and some shipping, since I'm getting the spider from them anyway.

Mike

I'm totally with Floyd on this one. I redid my 8" f5 and built a 12" f6. Both have an Antares quartz somewhere around 1/25 pv. The views are crisp.

Floyd said a while back; "it's a small mirror that does a big job."

Ed

But then I wouldn't be able to afford it!