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Re: Pistor & Martin's Prismatic Sextant
From: Brad Morris
Date: 2016 Dec 23, 09:10 -0500
From: Brad Morris
Date: 2016 Dec 23, 09:10 -0500
Herbert
The prism is completely clear, without any silvering.
In the first image, we can only observe the prism holder, not the prism itself. As the prism is part of the optical path, it must adjustable. It is by design and the prism holder facilitates that.
Nor can we observe the prism in images 7 or 8, but some of the adjustment mechanism for the prism can be observed on the housing.
So there is still no definitive evidence of the prism's presence. Just the adjustable holder. I would still directly ask the seller.
In image 9, on the left hand side, we can observe the rising shade (!) adjustment, and the rising telescope adjustment. As the pitch adjustment (!) for the telescope is part of the rising mechanism, it's safe to say that's there as well. The shades for the direct path and the reflected path are present. The telescope eyepiece shades are present as is the right angle eyepiece, which is another prism.
The main mirror, which is quite elongated, may need resilvering. It's hard to tell from the images.
Brad
On Dec 23, 2016 4:49 AM, "Herbert Prinz" <NoReply_HerbertPrinz@fer3.com> wrote:
Brad,
The prism is there. You can see it in the first picture, where the sextant is in the box. The shades are mounted directly on it.
A professional restauration would easily double or triple the price of this piece, if it can be done at all.
Herbert
