>>3271139While the epoxy cures on the front-element of the lens I mentioned in the previous post, I took the lenses out of the eye piece of the finderscope. There are 2 lenses and they are identical.
Specs,
Lens Diameter: 13mm
Focal Length: 30mm
F-stop: f/2.3
Working Distance: 3" (76.2mm)
The lenses are just slightly larger than a 1/2" drill bit (0.511") so it was easy to drill the hole in the cap then bevel it on the inside with the deburring tool from a pipe cutter. To affix one of the lenses to the cap I simply cut a rectangle of clear packing tape and taped it in place on the inside, seated in the bevel. Now I can use it simply as a cap on the camera (small dime photo) or on my bellows to get some more extreme macro (larger dime photo.) I'll probably think of how to install a simple aperture later on, if I want it to be clearer and without haze. The short focal length means I can't get infinity with this on my D3400 (FFD 46.5mm). Not that I'd want to, since being that close I think it'd have terrible tunnel vision, but this makes for a neat, super low profile, macro lens.
Here are the results.
