Zeiss Theo 010

[andrewjsmith]

Hi - I have just received delivery of a Zeiss Theo 010 Secundentheodolit. The instrument is in good order, but there seems to be an error in the adjustment of the vertical circle micrometer. The attached pic shows what I see when the vertical scale is selected. Is there anyone who has any experience of these instruments, and who can suggest how to correct the error ?

 

[andrewjsmith]

Here is a pic of what I see when the horizontal scale is selected

 

[dik]

It looks like something has been knocked out of adjustment... possibly a split prism or something. Is it possible to contact Zeiss and provide them with the photographs? I've an old Helger and Watts 5 second theodolite that's in nearly perfect condition... it's about 70 years old and it's amazing they built things like that... Similar super sharp optics... and the image is inverted through the scope. It's really intersting using the optical plumb...

Dik

 

[andrewjsmith]

Thank you Dik. I am hoping that I shall be able to correct it, but am reluctant to meddle with the instrument until I have a clear understanding of what I should do. I am amazed by the precision of this theodolite. I have previously used a Theo 120 for archaeo-astronomical investigations, for which it is adequate, but against the 010 it looks more like a mere toy !

If there is anyone out there who is familiar with using the Theo 010 I would like to ask some other questions - for example there is a mysterious knob attached to the telescope near the objective end, which visibly moves something inside the telescope if you look into the 'wrong' end of it, but does not affect the view through the eyepiece at all. Any comments on that ? I would also like to ask about the illuminator.

 

[BruceInKonstanz]

I hope this reply is timely; there is no year on the postings!
The knob on the Theo 010 telescope is for illuminating the reticle during night sightings. Turning it reflects light into the telescope tube from the circle illumination window.
The prism that joins the two opposite images of the circle is part of the micrometer optics, but as I remember it joins them after the circle selector switch, so the problem has to be located earlier in the optical chain, in the standard with the illumination window, opposite to the micrometer.
I fooled with this adjustment maybe 20 years ago and wrote up detailed notes. My notes say this is a very tricky adjustment because it affects the size of the circle image, which must match exactly with the size of the micrometer scale.
I can send detailed drawings and adjustment instructions if you want to contact me directly. It's a long document, about 660 kB.

 

[IRstuff]

?? The OP date code is 30 Sep 16 15:03 What part of that is confusing?

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529

 

[andrewjsmith]

Hi Bruce - Yes - your reply is most welcome. It would be a great help if you could send your notes. Here is my email address : aj-smith@blueyonder.co.uk.