Yes, I forget about nicotine, and the simple detergent/water shifting something better than alcohol is not something I would have thought of.
Removing,cleaning and replacing prisms is pretty easy, the problem is re - aligning the binocular afterwards, that's the bit that can drive you nuts. I have a home built collimation device, it works, but still can take hours or even days to get them aligned. I have a Jenoptem that I have been going back to on and off for months, it just wont align, I have aligned others in between, including Jenoptems, but I cant seem to get this particular pair right, horizontal is fine, but the right image shows slightly to the right of the left image and no matter what I try with the prisms and objectives it either gets worse or ends up back just the same, it just wont align.
Oh dear, that's exactly what I was afraid of.
I was thinking about using two cheap pointer lasers and some fixturing.
First shot was with objectives on...it's way too 'reactive' to placement.
I'm thinking...put the lasers at the right spacing 20 ft away, swap the
binoculars into the flow, no lenses. Live feedback. Of course, the real
problem then is...how to nudge the prisms. Maybe clamp the binocs
and use long rods to lever things.
I can do an awesome salvage on bumped binoculars with seperate L-R
focusers. Pull the pin, and voila, two monoculars. Alignment only has to be
approximate then. There are a few nice binocs in that era. Coatings not
always great, but the resolution can be impressive. I suspect hand-figuring
and slightly parabolic surfaces are what makes the image so crisp. A felt
hood on the front cuts glare, in lieu of coating. (they are all coated up front
but not all fully coated)
I have separated single-focus binocs as well. I can make a "trombone"
focuser with wall-anchors, 1/4-20 bolts and nuts, using the hinge mounts.
It's a little wobbly though. I need to make some precision parts. If I sliced
one of the hinge-mounts I could install a real focus wheel.
It's a lot of fun with the monster field-width binocs. Really surprises people.