G Hole and Son, Brighton

[moriniboy]

Got a secondary mirror with G Hole and Son, Brighton etched on the back, there does not seem to be a lot of info on the web about them, can anyone fill in the gaps?

Thanks in advance.

[moriniboy]

No this is not a spoof post lol

[Peter Drew]

George Hole was a well known telescope and mirror maker in the Brighton area. He collaborated with Sir PM occasionally via early Sky at Night episodes including the classic one trying to find something to look at with his self built 24" Newtonian, a massive telescope by the standards of the time.   

[moriniboy]

[JeremyS]

53 minutes ago, moriniboy said:

Got a secondary mirror with G Hole and Son, Brighton etched on the back, there does not seem to be a lot of info on the web about them, can anyone fill in the gaps

Very interesting to hear you have a George Hole secondary mirror. Is this part of an optical system i.e. is there a primary? The etch says 45" focal length

Jeremy

[moriniboy]

Yes Jeremy, got a f3/f9 classical cassegrain mirror set.

140mm secondary, 380mm primary

[geoflewis]

1 hour ago, moriniboy said:

Got a secondary mirror with G Hole and Son, Brighton etched on the back, there does not seem to be a lot of info on the web about them, can anyone fill in the gaps?

Thanks in advance.

You might find this interesting...

http://www.britishpathe.com/video/garden-telescope

[JeremyS]

2 minutes ago, moriniboy said:

Yes Jeremy, got a f3/f9 classical cassegrain mirror set.

140mm secondary, 380mm primary

This is very interesting indeed. Are the optics mounted into a usable telescope? Or is this a project? Any more photos? Do tell us more.

If you have access to Martin Mobberley's biog of Patrick Moore, "It came from outer space wearing an RAF blazer", there's a bit of info about Hole e.g. pg 90 to 92. He was a very good friend of Patrick's (and you will discover some amusing stories if you read Martin's book!). Hole was active in the BAA, becoming Director of the Instruments & Observing Section in 1961

Jeremy

[moriniboy]

Its sort of a project i.e. not sure if its worth changing use to an f3 dob or keeping it as a cassegrain.

The mirrors come from UCLAN's multi aperture telescope and this has now been replaced by an all singing and dancing modern version which was recently installed by Green Witch.

[moriniboy]

Mirror specs

[skybadger]

I have a George Hole cassegrain set too. 12.5" f/10 I think. I am currently using a double-pass ronchi oil mirror rig to work out the secondary spacing distance.  What I do know is that one of the mirrors is very zony. I suspect its the secondary which has been polished on a small polishing jig and the primary didn't show much at all at f/2.7 in foucault testing. 

Once I get the secondary distance right, I'll be sending it to Nicholls for testing and re-figuring. 

I'm jealous yours is etched. 

Mike

[skybadger]

Where did the rest of the scopes go ?

Where can I get one ?

M

[moriniboy]

I will PM you

[PeterW]

Dobsonian!!!!!!.... a 14"f3 (with a corrector and 20mm ultrawide eyepiece will Hoover stuff up, a special kind of scope!! If there are more of those primaries in the wild it would be interesting to dob them up too!

cheers

 

peterW

[Peter Drew]

5 hours ago, PeterW said:

Dobsonian!!!!!!.... a 14"f3 (with a corrector and 20mm ultrawide eyepiece will Hoover stuff up, a special kind of scope!! If there are more of those primaries in the wild it would be interesting to dob them up too!

cheers

 

peterW

I think this would be my first approach as well.  

[PeterW]

Peter... thought you were a binocular fan... seems to be enough mirrors available for that....

peter