Astro Sytems F4.3 ten inch Mirror required

[stevear]

I have an old 1980's Astro-Sytems 10" reflector. Unfortunately the mirror is damaged  and I need to replace it.

I have tried Orion who I know make an F4.8, I asked if they could do an F4.3 but got no reply. 

Does anyone know where I can obtain an F4.3 10" mirror to resurrect this very good scope?

Thanks

Steve

[alan potts]

Hi Steve,

I don't know if he will but you could try John Nichol Optics, I have one of his larger mirrors and it is absolutely excellent.

Alan

[Uplooker]

+1 for John at Nichol Optical

http://www.nicholoptical.co.uk/

[alan potts]

Uplooker,

I must learn how to add a link, thank you for doing that.

Alan

[NGC 1502]

I have an old 1980's Astro-Sytems 10" reflector. Unfortunately the mirror is damaged  and I need to replace it.

I have tried Orion who I know make an F4.8, I asked if they could do an F4.3 but got no reply. 

Does anyone know where I can obtain an F4.3 10" mirror to resurrect this very good scope?

Thanks

Steve

Hi Steve.  When you say the mirror is damaged, do you mean just the coating ?

OO UK do recoats, as do http://www.galvoptics.fsnet.co.uk/telescope7.htm

Those old Astrosystems were cracking scopes, I had an 8.5" F5 on a bomb proof aluminium alt-az mount, and was barmy enough to sell it......

Regards, Ed.

[stevear]

Ed. Yes I mean it has a chunk out of it. The secondary hit the main mirror at some point in the past. Its beyond re-grinding.

I have tried John Nochol and I'm sure his mirrors are excellent. He only makes 12" and upward.

Steve

[Uranium235]

Cant you just go with an f4.8? After all, the only side effect is that your focus point will be pushed outwards (will require extensions).

[Peter Drew]

How big a "chunk"?  

[ronin]

I see that TS do an f/4.7 mirror, so an extra 101mm which I suspect may be bit much. The light cone could start hitting the focuser.

One place may be Hubble Optics. They make sandwich mirrors, and are in China or Taiwan. Probably a last resort however.

Their site goes down to 12" but they list supplying enhanced coatings on 8" and 10" mirrors so I guess from that that they make 8" and 10" mirrors.

They do seem to have mirrors in the f/4.5 to f/5 range.

At a guess a mirror would be sort of $700 area, then shipping and customs, so I doubt inexpensive, looking at $1000 so £650. BUT it is literally all guess work.

Also the communication with them could be stressfull I suspect.

[NGC 1502]

Ed. Yes I mean it has a chunk out of it. The secondary hit the main mirror at some point in the past. Its beyond re-grinding.

 

I have tried John Nochol and I'm sure his mirrors are excellent. He only makes 12" and upward.

 

Steve

As Peter Drew mentions, how big a chunk is missing ? My local clubs 16" Dob has a "chunk" out of one edge of the optical surface, this has been blacked out, and it works fine, although perhaps not ideal.

The Newtonian secondary blocks the centre of the primary, same as a missing area elsewhere.

BTW, Peter Drew was a leading part of Astrosystems.

Hope you find a way to sort it, Ed.