cracked corrector plate in SCT

Well, the dreaded happened, and while adjusting the
dovetail of my new (to me, anyway) SCT, it slipped.

I almost caught it.

The cover was on the front, which stopped anything directly hitting it,
but theres a big crack in the corrector plate. The mirrors look fine, and
I can focus (haven't tried anything in depth yet, so I'm not sure how bad)
but I want to fix this.

How difficult / expensive is a 203mm Meade corrector plate to replace ?
How would I go about it?

Alastair

OMG !, well, it was only a matter of time before something like this happened to someone on these boards, I always though it would be me smashing the secondary mirror while collimating it.

Alastair, the bad news is that the primary and secondary mirrors and the corrector plate are all optically matched, you just cant replace one component, you have to replace all of them. So, its an expensive trip back to Meade in California or maybe think of this as an opportunity to upgrade the scope by getting a new one. Can you put up a pic of the damage?

That is bad luck Alastair, sorry to read about it! Is it a single crack from the centre to the edge? Or right across the plate? if it was a single crack, that's all it might be? I mean, it might be useless for really dep sky work, but it *might* not affect seeing of things like Solar System bodies close-up, bright galaxies, and nebulae, and the like... Only one way to find out.

Whoa! That's really bad luck Alistair, particularly since you have it for such a short time.

I don't think looking for a replacement plate would be a good idea as they are apparently matched to the individual primary mirror in the scope as Dave rightly mentioned. The best bet would be to email Meade in Germany. I've found them decent enough on support. They may agree to fixing there.

Try both service@meade.de & service.apd@meade.de. It was the APD guys that fixed my PST.

Hope it works out for you.

Trev

Yikes! :oops: Thats terrible Alastair!Dave i dont think upgrading is an option as alastair only bought it maybe a month ago. Alastair i have seen sets of optics on ebay(ie primary + secondary mirror and a corrector plate) for sale! For meade 8" SCTs but they are quir=te rare to come by.You could get the crack repaired. I know there is a guy in the UK who repairs them, ill try and source him, i saw this on another discussion boards.
Matthew

Repairing a cracked corrector plate is not really an option. The crack will have released stresses in the glass created during the grinding and figuring of its torus shape - even if it was annealed beforehand. You will also get diffraction effects from the crack. To see just how bad it is, star-test at high magnification and examine the diffraction pattern - you'll need a night of steady seeing to do this right. Your best bet is to contact the manufacturer for their advice.

Commiserations, dude, that's seriously bad medicine!

Phil.