Camera Eyepiece M19x0.75mm

According to kamerastore, an original Nikon 2925 fits the following camera models:

• Nikon F, F2 (w/ DE-1, DP-1, DP-2, DP-3, DP-11 & DP-12 finder), F3 (w/ DE-2 finder), Nikkormat, FM, FM2, FM2N, FM3A, FE, FE2 & FA
• Fujifilm X-Pro 1, GS645
• Zeiss Ikon ZM
• Voigtländer Bessa R2A, R2M, R3A, R3M, R4A, R4M

This eyepiece has the same M19x0.75mm thread and was designed and tested to fit (fairly well, not perfectly) on an FM2n, so it should be a usable substitute for the other models above as well.

Print with the threads on top, which should be the model's natural orientation. I printed it with PETG but it would make sense in TPU or other flexibles as well, to help prevent scratching eyeglasses.

OpenSCAD source file is included in case it's useful for tweaking tolerances or adapting to other thread sizes for other cameras.