18 replies to this topic

[kjkociba]

I know it's a long shot,  but by chance has anyone ever run across an early zeiss 70mm X 70CM?    I picked up a bare objective, NR - 14544, Cell is identical to the early astro lenes, but it doesn't have any OBJ - type marked, (AS, A, B, etc).  Lens is foil spaced, fairly thin glass, and after I made a temporary OTA, (Dont laugh, good old cardboard), gives pretty good views, tad of false color, not surprising with f/10, with stars are nice dots through field edge, with slightly off center but round airy disks probably due to nature of the OTA not being optically true.  looking through old zeiss catalogues I have access to, I can find no mention of this FL combo.    Here's a pic of the lens in cell.    Now I wish that I had picked up the old zeiss cadaver I saw on ebay a year and a half ago.  but alas, hindsight truly is 20/20.

 

 

Any info would be appreciated, and will probably email Zeiss if I don't find any public info on it.

 

Album: zeiss 70CM F/10

11 images

0 comments

 

[Astrojensen]

Unusual! Never seen one before. Zeiss made a lot of one-offs, though. Could make for a superb little grab and go. 

 

 

Clear skies!

Thomas, Denmark

[Terra Nova]

I know it's a long shot,  but by chance has anyone ever run across an early zeiss 70mm X 70CM?    I picked up a bare objective, NR - 14544, Cell is identical to the early astro lenes, but it doesn't have any OBJ - type marked, (AS, A, B, etc).  Lens is foil spaced, fairly thin glass, and after I made a temporary OTA, (Dont laugh, good old cardboard), gives pretty good views, tad of false color, not surprising with f/10, with stars are nice dots through field edge, with slightly off center but round airy disks probably due to nature of the OTA not being optically true.  looking through old zeiss catalogues I have access to, I can find no mention of this FL combo.    Here's a pic of the lens in cell.    Now I wish that I had picked up the old zeiss cadaver I saw on ebay a year and a half ago.  but alas, hindsight truly is 20/20.

 

 

Any info would be appreciated, and will probably email Zeiss if I don't find any public info on it.

 

I wonder if it could be part of an old military telescope or spotter, like a quartermasters telescope, or maybe an artillery spotter.

[Astrojensen]

I wonder if it could be part of an old military telescope or spotter, like a quartermasters telescope, or maybe an artillery spotter.

It's not impossible, but they usually had very different lens cells. This looks like a genuine astro objective. It could have been from a finderscope for a larger scope. Maybe someone with the Diarium could look it up, if the serialnumber is not too high. 

 

 

Clear skies!

Thomas, Denmark

[kjkociba]

Exactly!  and is the main reason I picked it up, most of the oddball zeiss lens cells  for terrestrials that I've seen look more like a front element from a camera lens (diatar, tessar, etc)

[kjkociba]

serial # is right towards the end of the missing section of the zeiss online archives,  Oh well. It will be a great portable rig after I build a period tube!

[Dave Trott]

Good plan! Maybe you can find a nifty Zeiss focuser. Very fun project!

Edited by Dave Trott, 08 June 2022 - 07:57 PM.

[kjkociba]

Chuckle. It was a thought! I have been put in touch with a wonderful brass focuser that will work just fine (thank you, you know who you are) Although not a zeiss, it looks the period. I actually prefer it that way as this isn’t a restoration. Zeiss focusers seem to be rarer than the glass, and are rather well documented, I would rather a serialized focuser be found and used by someone with the matching objective size. Hope that makes at least some sense.

[kjkociba]

Ok. After a brief design phase based upon what I had in the parts bin,  acquiring a focuser (thank you again!),  fixing said focuser (sorry again) machining a cell holder and assembling, here’s the naked OTA!  Had to trim down the ota once to accommodate the diag. It focuses all my EP’s both with diag and drawtube.

 

[Dave Trott]

This is well on it's way to being a first class resto-mod! Looking great!!

[kjkociba]

resto-mod. I like it!  Fitting as I have been unable to find another example to base a rebody restore on!  

[Astrojensen]

Hey, that doesn't look half bad! What mount is that? Can't quite recall having seen one like that before.

 

 

Clear skies!

Thomas, Denmark

[kjkociba]

Thanks! The EQ mount, I believe, is an old anchor/ Edmond head that I had without a declination shaft/ mount plate. I machined a new one to fit my old refractor (bardou) It has 2 bolts through the OTA at center of balance that I was always worried I would loose or damage the internal plates taking them out to fit modern clamshells/rings. This OTA is temporarily held on using high tech hose claps until I get the balance right. Setting circles are from the parts bin.

[kjkociba]

Now with my antique finder scope…  plan is to varnish my brass cell to match the finders cell and OTA focuser. Jury is out with how to finish the main tube…

 

[Dave Trott]

You could keep it the way it is right now with the hose clamps and the somewhat decrepit appearance. It would be a sort of Rat-Rod telescope. Rough looking but highly functional. Cool if you ask me. 

[kjkociba]

Possibility … Rat rod 70/700… astronomical version of a new frame model T with an original Offenhauser?

[kjkociba]

Well, after much consideration, decided to give the main OTA a coat of off white paint, and affix mounting bolts. Although the hose clamps had a certain charm, was a pain to balance it out for different tail accessories.  pretty happy with it optically, after recentering the tail, and truing the objective side tube face, I have well defined airy disks using my 8mm brandon!

 

[Dave Trott]

WOW!! That is pure class!!

[oceanoprofondo7]

Top class!!!