[FrankD]

Just out of curiousity, has anyone attempted to mate a binocular eyepiece with a spotting scope?

Here is the story....

I was "refurbishing" a classic porro that I picked up on the bay a few weeks ago. It had collimation issues and was quite dirty internally. I took the entire binocular apart, including all of the individual lenses for the eyepiece. When I reassembled it I was struck by the realization of just how similar the eyepiece design was to many of the 1.25 inch astro eyepieces I had disassembled for cleaning...not only the lens arrangement but also the size of this particular eyepiece in relation to a 1.25 inch astro unit.

So, I think I may experiment with this issue a bit over the next few days. I have several classic porros that are in the "project drawer" and are worth experimenting on. I will certainly post my findings but am curious if anyone else has tried this in the past.

Comments and suggestions are certainly welcome.

[henry link]

Frank,

I've done this many times. In my eyepiece drawer now I have a few binocular eyepieces including Fujinon FMT-SX 16x70 and Nikon 8x30 E eyepieces converted to 1.25". Most of the time binocular eyepieces work better in higher focal ratio telescopes, but sometimes they're worse when the binocular prism aperture vignetting is removed from the edge of the field image. The Zen-Ray 30XW is a knock-off of Nikon SE eyepiece, so that's an easy way to acquire one of those.

I don't think you're likely to run into anything very good in the old Japanese Porros. Most of those use Kellners or Erfles or the occasional Konig.

Henry

[FrankD]

Thank you Henry. I had a feeling you would be chiming in. The info is appreciated and it was actually your comments about the ZR 30x and the SE that got me into this train of thought.

I will see what I can do with what I have on hand.

If nothing else it might also give me a reason to pick up some of the "for parts...not working" binoculars up for sale now.

[woodhornbirder]

`s to many of the 1.25 inch astro eyepieces I had disassembled for cleaning..`

could either of you chaps make a vid about this? or is it too much of an arcane science for the masses?

AM always up for fiddling about, but tbhi dont have a good grasp on the theory of lenses ie i avoided physics at school and did biology instead.

[FrankD]

Stephen,

I wouldn't have a problem disassembling an astro eyepiece and posting something to you tube. How beneficial it would be is the question. Though many astro eyepieces share similar designs there can be notable differences between similar models.

Last summer I disassembled a Orion Epic ED II. Somewhere in the process I did not keep track of the exact arrangement/position of some of the lens elements. Luckily, after some intense internet digging I found someone that ran into the same issue and had posted about it on a message board. One of the replies actually had a nice 2D diagram of the correct arrangement of the lens elements.

Basically you just need a spanner wrench, optical cleaning solution, some microfiber cloth and a can of compressed air. Then take pics or notes of the lens/spacer arrangement upon disassembly.