So, I've been hashing ideas for a large binoscope for a few years, but recently two things happened to give the project a huge jolt forward:
I haven't finalized the specs yet, the primaries will be more than 30 but no more than 50in.
I'd be up for doing something similar if I could convince myself that the law of diminishing returns might make the expense and effort worth it.
Well, there would be some degree of upside if a couple of us were building roughly the same instrument.
For example, ordering a custom secondary mirror designed for a non-standard fold angle is a very different proposition to placing an order for 6 of them.
Likewise, coating a single secondary mirror with the dielectric layer thickness optimized for non standard angle of incidence would be an expensive proposition. It becomes a whole lot more affordable if there were 8 big flats in the chamber at the same time.
CNC machining of the opto-mechanical support structure also benefits hugely from standardizing fixtures and tool paths.
There is also the benefit of having others help drive the process along...
Where I am at is that I have already locked in 40" f3.75 (first optic should be finished later this year.)
I have a pair of 20" f3.75" primaries that will be used as a path finder instrument.
First make a 20" f3.75 monocular as a test mule for the compliant merger-pivoting cell.
2nd, upgrade it to a bino.
3rd, build a 40" mono.
4th upgrade it to a bino.
The idea is to add one significant variable (or innovation) at a time rather than doing the full greasy balloon squeeze all in one go.
Well, that's what I am doing, for what it is worth.
Edited by clivemilne, 13 May 2021 - 04:50 AM.