2024 amateur optics / astronomy updates
What I’ve done this year on the amateur astronomy side. I wrote this list to clear my mind about what was ongoing, stalled, done, and what would go in a whishlist. Looking back, quite a lot was achieved, even if everyday progress is tiny or null most of the days.
Aside of what I have personnally done, what is truly remarkable is the growth of our french-speaking Discord group, hosted on the large french Astro-FR server.
Two years ago, when I gave this talk on making a mirror, I was the only glass pusher on this discord server and had a little thread where I posted experiments.
Today, we have a real “amateur optics” channel, with a dozen or so people participating, a lot of people lurking, and 5 active glass pushers. I am not the most experienced mirror maker of the server anymore, by far, and learn a lot.
Done :
- Built and released the open XYZ table for interferometry.
- See it here on the blog.
- Brought a 6” f/2.8 mirror to a λ/4 figure, and scratched it badly.
- Fine ground and polished this same mirror to a better figure, and built it Wallace, a tiny but mighty dob.
- See the figuring thread on CN and the scope on CN
- Finished a 10” f/5 mirror with a quite smooth figure, after a bit of a fight with astigmatism.
- See the figuring thread on CN
- Designed and built two 6” f/5 travelscopes, with integrated counterweights so they’re not limited eyepiece-wise.
- Fine ground and polished my 16.5” f/3.2 porthole to the point it’s ready to figure.
- See the ongoing thread on CN
- Modified my polishing machine to be able to use it as a turntable or for spin polishing.
- Fine ground and started polishing three 8”x1” flats for my friend’s 16” dob secondary
- Started rough grinding my friend’s 16” f/4.1 primary
- Printed a LOT of 1:10 crayford reducers to give feedback on my friend’s design. GO PRINT IT !
- See it on Printables
Backlog :
- Polishing my 85mm f/15.4 doublet.
The glass is currently in fine grinding and needs a bit of ROC matching work.- See the stalled thread on CN
- Figuring two 6” f/5 mirrors for the two travelscopes.
- Figure the 16.5” f/3.2 porthole, design and build its telescope.
- Polish and figure a 6” f/2.8 plate glass meniscus for my friend.
- Build a Fizeau tower to test the flats
- Finish the flats
- Help my friend grind and polish his 16” f/4.1
Stalled :
- The robo-scope I built and wrote software for.
It was initially meant to be a bird-watching camera because of a nearby lake that a lot of birds visited at fall, but we moved and the project halted. Since I do not practice photgraphy nor astrophotography, motivation to build on this project ground to a halt.
Wishlist :
- Build a small (220mm) mirror-o-matic to slash through all the small mirrors I have to repolish and figure.
- Build on my Nerves experience that started for the robo-scope to add features to Wallace that I would actually need (and use). In order of importance : active dew control, motorized collimation, digital setting circles, pointing app. Note that what is most important is also the most trivial to program, and the reciprocal is true.
- Gift a few telescopes, notably :
- The two 6” f/5, that will not see a lot of use with me
- The 4” f/15 solar maksutov
- The 85mm f/15.4 doublet in a cell, for someone to build a long focus refractor with