If you want to take pictures of tiny things close up, you need a macro lens. Or a microscope. [Nicholas Sherlock] thought “Why not both?” He designed a 3D-printed microscope lens adapter that you can find on Thingiverse. Recently, [Micael Widell] tried it out with a microscope lens and you can see the results in the video below.
A $20 microscope lens allows for some amazing shots. There are two designs that fit different cropped-image and full-frame cameras. As you might expect, the depth of field is razor-thin, probably sub-millimeter. Additionally, with a 4X lens on a 35 mm sensor, the field of view is about 9 mm so you have to have a steady hand just to keep everything in frame.
[Micael] also bracketed the focus to get several shots that could be postprocessed to provide a deeper apparent depth of field. He has a different video that covers the process he uses. You also need a lot of light since the lens is effectively f/20.
Using this by hand probably requires more patience than most of us have. However, we could see a use for this if you had the camera mounted in a studio. Then again, you could use a camera mount for an actual microscope, but maybe not at this price.
The results are impressive. We also noticed that printing in PETG caused some problems because it is shiny. You can either paint the interior of the tube or use ABS which is not very shiny.