As the UK enters another phase of lockdown it is important to keep busy. Do you have a box of old camera gear that you keep but will probably never use? Go through it with a different mindset - what use can I make of it?
My moon camera project work had defined two problems when it came to integrating a DSLR. Using the camera body without a lens left the image open to stray light and dust on the sensor. The solution needs a closed tube with defined geometry with some clear glass on the end to let light in but keep dust out. Time to delve into the toybox.
I did a project years ago putting DSLRs onto telescopes through the eyepiece tube. These have a 2inch internal diameter and a bit of geometry suggested a 75mm length would be a good balance between stray light removal and vignetting on a crop sensor.
I also have a selection of old camera filters. A 49mm filter was close to right and careful use of a file on the male thread converted it to a push fit on the eyepiece tube. One stray light baffle with a daylight filter optical window.
Build stuff and keep busy.