USB Microscope — a zoom function for the real world

[Read the post]

250x? How does this compare with a macrophotographer’s 1:1, 2:1, etc?

A bit of math leads to an answer, in terms of the frame field of view:

The George eyeball on a real $1 bill is about 7mm wide, and fills the USB microscope frame at “50x”. A 1:1 lens turns a 24mm x 36mm object into an image on 35mm film of the same size. Thus the equivalent magnification at 50x is about 36mm/7mm ~= 5, or a 5:1 macro lens.

Bear in mind that a frame of decent 35mm film has more than 2 million pixels.


If it has decent depth of focus, and is not too heavy, it could be added to e.g. a 3d-printer tool head to monitor the work. Or to a laser cutter to both monitor the progress and to finely align the object (and possibly to autocalibrate the power and speed to match the material in use, by running a test pattern and inspecting the result and choosing the best).

1 Like

FREEZE. Zoom in. And enhance.


This is 1:1; cropped to 1080x1920.
Yeah, I need a tripod, and a flatter bill.

Check if the thing can see near infrared. Then try out near-IR illumination, and a NIR filter for the microscope lens that removes visible light. A word goes around that IR-absorbing inks are used as a security measure in addition to the well known UV-fluorescing ones.

UV fluorescence microscopy could also be a fun thing to try.

Oh, that’s my camera, not this USB microscope.-- I was trying to get a handle on the 50x thing.

Ahhh. Nice, too! (And the same suggestion applies to other optics too. :smiley: And you can make a whole-area image too.)

This topic was automatically closed after 5 days. New replies are no longer allowed.