What the heck is this?

[Kino]

Just bought out a old timer's darkroom, the requisite 5x7 Elwood, tons of old paper (yes AZO!), chemicals, weird lens elements and ... this.. viewfinder ... thingy.

Might not be photographic, as he was a surveyor and there were a few boxes of 10x10 aerial glass plates laying around (not part of the deal).

The tube has a simple (as far as i can see) lens on one end with a fixed aperture on each end. The middle brass tube has a 3 position filter wheel that bring a clear (empty) hole, a very dark violet filter (looks like a Milk of Magnesia glass bottle) and the third is a very thin slit.

From its generic construction, it looks like it could have been built anywhere from the early 1700s to the 1920's.

Any clue as to what it is?

Frank

 

[JBrunner]

Just bought out a old timer's darkroom, the requisite 5x7 Elwood, tons of old paper (yes AZO!), chemicals, weird lens elements and ... this.. viewfinder ... thingy.

Might not be photographic, as he was a surveyor and there were a few boxes of 10x10 aerial glass plates laying around (not part of the deal).

The tube has a simple (as far as i can see) lens on one end with a fixed aperture on each end. The middle brass tube has a 3 position filter wheel that bring a clear (empty) hole, a very dark violet filter (looks like a Milk of Magnesia glass bottle) and the third is a very thin slit.

From its generic construction, it looks like it could have been built anywhere from the early 1700s to the 1920's.

Any clue as to what it is?

Frank

Looks allot like a theodolite tube.

 

[Kino]

Looks allot like a theodolite tube.

As in for a telescope? Other than a curiosity, it doesn't seem to be of much practical use for general photography...

 

[JBrunner]

No, I was thinking more along the lines of a sextant, or old pocket surveyor.

 

[athanasius80]

The blue lens makes me wonder if its part of some sort of extinction meter.

 

[Ole]

Sextands tend to have very dark filters for observing the sun; this doesn't look anywhere near dark enough except near sunrise/sunset. But I too think it's from some kind of surveying equipment.

 

[Woolliscroft]

Why not ask the "old timer"?

David.

 

[Jim_in_Kyiv]

Why not ask the "old timer"?

David.

That would be too easy, and then where's the fun for us?

It looks like one end - the 'right hand' end in the image - is threaded. Is it?

 

[Kino]

That would be too easy, and then where's the fun for us?

It looks like one end - the 'right hand' end in the image - is threaded. Is it?

Yes, it is very crudely threaded; at first I thought it was simply turned decorations, but I found the start and end of the thread -- all heavily worn.

 

[Kino]

The blue lens makes me wonder if its part of some sort of extinction meter.

That is what I thought at first, but the slit didn't make sense in that context (at least to me).