1880's Harbourmaster's telescope
Posted 27 January 2014 - 03:32 PM
It is ± 4", ± f/10 or so, brass tube and dewshield, brass and wood alt-az mount/tripod, several eyepieces in individual focusing tubes. I'll post some pics once it is assembled.
How can I find out who made it and when?
Posted 28 January 2014 - 12:39 AM
Posted 28 January 2014 - 04:13 AM
Posted 29 January 2014 - 01:41 PM
It is genuinely old, real patina on brass, real fungus on glass (as far as I can tell but in Durban's humidity who knows?). I'll sort some pics and clarify it's history. Hopefully not a fake.
Scope belongs to a friend, I won't be buying it :-)
Posted 30 January 2014 - 04:14 PM
Posted 31 January 2014 - 08:03 AM
Posted 31 January 2014 - 10:19 AM
The tripod also looks vintage, though someone polished the brass at some point (or it was hardly used).
Posted 01 February 2014 - 02:37 AM
Posted 02 February 2014 - 06:12 AM
Posted 02 February 2014 - 06:14 AM
Posted 02 February 2014 - 06:16 AM
Posted 02 February 2014 - 06:29 AM
The alt-az mount is solid brass and beautifully damped. The tripod and mount look to be partially restored with the brass polished up.
Posted 02 February 2014 - 07:56 AM
Posted 02 February 2014 - 03:08 PM
Posted 02 February 2014 - 05:11 PM
Posted 02 February 2014 - 06:29 PM
That cracked objective is a crying shame, but I wouldn't mess with it. It would be a doublet.
Posted 03 February 2014 - 04:39 AM
That lens cell is almost exactly the same as my 3.25" F15 c1865 Berry&Mackay, the lens should be a contact doublet held in place by a blackened brass retainer with knurling the same as the front rim.
there should be some screw holes on the right side near the drawtube that were for attachment of an altitude adjuster.
These scopes were some of the first examples of "badge engineering" in scopes. The back plate was usually customised for the retailer.
Posted 03 February 2014 - 04:49 AM
Ok, here are some pictures. First the objective lens - 93mm clear aperture, looks like a single piece but not sure.
On the back of this cell will be a blackened knurled retainer which will unscrew (use rubber gloves for grip with your palms flat as if you're praying and then twist - this avoid deforming the very thin brass). The lens elements are held in place only by this ring, try to avoid rotating the glass
Here is a pic of the focuser on my Berry & Mackay. These scopes were made under several names.
Posted 04 February 2014 - 12:54 AM
I'll see if I can strip the focuser this weekend and get it working.