I bid on a reticule slide on eBay last week.
I lost the bidding which went to $36 plus.
I was surprised.
So I pondered making one.
One could take a 35 mm black and white
photo at a suitable scale to produce a 100 X 0.01 = 1 mm
graticule. But I would be uneasy with it - even stuck on a glass.
Plastic is so inconstant in size.
I considered a gelatin/bichromate coated slide approach, but I was
disappointed to read that I could not expect great resolution.
This photoresist method might allow a hydrofluoric acid etch
(dangerous though it is...)
So then I looked into liquid photo emulsions.
They seem to run $22 to $29 for the minimum sale quantity,
of 8 ounce or 250 mL depending...
and if the gelatin doesn't peel (countered by a substrate of
synthetic lacquer.) one could develop, fix, and cover.
I hear someone whispering there is another method,
more accessible, more convenient.
I wonder what it is?