Google Pixel 3a Microscope Adapter

Hand-holding my Google Pixel 3a phone over the microscope eyepiece worked well enough to justify building Yet Another Camera Adapter:

The solid model looks about like you’d expect:

The “camera” actually has the outside dimensions of a Spigen case, rather than the bare phone, because dropping a bare phone is never a good idea.

The base plate pretty much fills the M2’s platform:

I originally arranged the four corners around the plate to print everything in one go, but an estimated six hours of print time suggested doing the corners separately would maximize local happiness. Which it did, whew, even if the plate ran for a bit over 4-1/2 hours.

The snout is a loose fit around the 5× widefield microscope eyepiece, with the difference made up in a wrap of black tape; it’s much easier to adjust the fit upward than to bore out the snout. An overwrap of tape secures the snout to the eyepiece, which I’ve dedicated to the cause; the scope normally rocks 10× widefield glass.

The tapered hole exposes the phone’s fingerprint reader to simplify unlocking, should it shut down while I’m fiddling with something else.

The microscope doesn’t fully illuminate the camera’s entrance pupil at minimum zoom, with 4.5× filling the screen and (mostly) eliminating the vignette. The corner blocks have oversize holes to allow aligning the camera lens axis over the microscope optical axis. The solid model incorporates Lessons Learned from the version you see here, because you (well, I) can’t measure the camera axis with respect to the outside dimensions accurately enough:

Although it’s less unsteady than it looks, microscopy requires a gentle touch at the best of times. The adapter doesn’t add much wobble to the outcome:

The field is about 14×19 mm with the camera at 4.5× and the microscope at minimum zoom:

You can see a little darkening on the upper and lower right corners, so the phone’s still minutely leftward.

The field is about 1.5×2 mm at full throttle:

Color balance with the cold white LED ring isn’t the best, but it’s survivable. Mad props to OpenCamera for exposing All. The. Controls. you might possibly need.

The OpenSCAD source code as a GitHub Gist: