Summary

An adapter to attach a Logitech C260 webcam to Canon EOS (EF / EF-S) lenses. It replaces the front panel of the camera. I also include separate files just for the front panel of C260, and just for the female Canon EOS adapter - they should make it easier creating similar adapters for other mounts. Both STL and the original (SketchUp) files are included.

If you use the SketchUp file to remaster the model, make sure to Explode All at the end, and get rid of the two internal surfaces (e.g. by running it through the Solid Inspector plugin).

As my measurement of the distance to the C260 sensor is not precise (it's accurate to ~0.25mm), and also because individual printers might print the adapter's height with some inaccuracy (say ~0.2mm), this adapter will likely not be useful for wide angle lenses without some fine tuning (as they are much more sensitive to the register distance accuracy). You should probably be okay for focal lengths >= 50mm. It works well with my Canon 70-200 F4L.

This might also work for other similar Logitech cameras (like C270 etc) - you'll have to test it yourself.

The primary goal of this modification is to be able to use C260 for astrophotography. I can now either attach it to my Canon 70-200 f4L lens, and use it as an auto-guiding camera for my 6" Celestron reflector, or attach it to the Celestron using an EOS-telescope adapter. In the latter case, the camera can be used as an autoguider using my telescope as a guide, or can be used for taking Moon/planetary shots in the prime focus of my telescope.

I printed it using Cura, with the EOS adapter side down, using "supports everywhere" option, 0.2mm layers, and 100% infill. Make sure to use a slower printing speed for both outer and inner walls.

It'd be a good idea at the end to sand the inside of the adapter, and then paint the inside with black acrylic paint - this should eliminate the stray light.