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25x100 binoculars are f/4.5 achromats. Hmmmn

Started by BoyntonStu, 04/16/2006 05:53AM
Posted 04/16/2006 05:53AM | Edited 04/16/2006 05:58AM Opening Post
Just thinking out loud here:

Close to a 25x100 f/4.5 OTA is a 120mm f/5 short tube achromat.

Wouldn't a pair of Orion Astroview 120ST's made into a binocular be something to salivate about?

Advantages: Bigger aperture.
Interchangeable EP lenses.
Better viewing angle with star diagonals.
Wide range of IPD adjustment
Choice of correct or astro view.

Additional parts needed: 2 helical focusers
2 mirror dagonals
2 prism diagonals (or 2 miror)
For astro viewing: 2 mirror diagonals.

Work required: Shorten OTA's to extend backfocus.
Fabricate mount for co-collimation. We can borrow the bi-Newt ideas here. A center post with orthogonal bearings is the one that I would choose.

Comments, questions.