chantepierre · 10 days ago

Hi, thank you !

I am using DFTFringe ( https://github.com/githubdoe/DFTFringe ) with a Bath interferometer (specifically this model which is super handy : https://www.printables.com/model/986094-multi-bath-interfero... ) and this 3-axis table which is bulky but simple to build ( https://www.printables.com/model/860316-xyz-platform-for-bat... ).

I am also trying to automate the XYZ table, capture and analysis like WavefrontPro does, I have a POC going on that bases itself on a CLI-only build of DFTFringe + outside orchestration with Elixir. My goal would be to control everything with a gamepad and automate the whole test session. Here is a video : ( https://www.youtube.com/watch?v=ii2eGb7vbk4 ). But I need to throw the code away and rewrite it.

chantepierre · 10 days ago

To me, there are two models that stand out from the crowd :

- The Hadley, a 4"1/2 f/9 dobsonian telescope, which is a smaller aperture but easy to build and to find optics for, and very mature : https://www.printables.com/model/224383-astronomical-telesco...

- The "open smallest telescope" from a friend, which I show here, a foldable 6inch f5 dobsonian : https://lucassifoni.info/blog/2025-best-6-inch-f5-150-750-po... and can be found on Printables : https://www.printables.com/model/1325533-ost-open-smallest-t...

Both are very cool projects, the smallest shows more for deep sky but costs a bit more in optics, and the Hadley has a very mature community.

bluGill · 10 days ago

How into this will you get? If you just want to make your own a small telescope is easiest (see the other reply). As things get large expenses go up. Commercial lens are cheap for smaller telescopes, but as you get to large that becomes the cost and so making your own is the only way you can afford it. If you want a large telescope you should again start making a small one, but this time making your own lens - even though it isn't cost effective to make your own lens (vs buy), the experience means you have a chance to make a larger one (and finish, most people who set out to make one large telescope never finish, those set out to make a small and then a large are more likely to finish both).

If you just want to see the stars, goodwill often has telescopes cheap. A refactor can see more than your eye. (or even the binoculars you likely already have!). And the bigger reflectors are seen once in a while.

GloriousKoji · 10 days ago

I built a Hadley 114 over the course of 3 weekends and I highly enjoyed it. Amazon has a convenient 2 piece mirror kit you can buy. The rest of the parts (springs, screws, rods) can be acquired anywhere and the stand can be as complex or as simple as you want.

giantg2 · 10 days ago

Just go down the rabbit hole like I have over the past year...

Find thick glass on Facebook, build a cutting jig, build a kiln to fuse it, etc. I'm still planning to build an 18".

chantepierre · 10 days ago

Hi ! It is quite easy, with 2 tilt screws at the secondary cage, and the primary cell floats on three heavy duty springs. I can shake it and nothing moves, this is my first criteria. I collimate with a cheshire tool but always finish on a star at medium power (since this telescope realistically does not reach high power, since it would need 2mm eyepieces which are the opposite of wide field views). I use it with Explore Scientific 17mm 92 degree, and a 13mm APM XWA 100 degree eyepieces, and do star collimation with a 6.7mm eyepiece.

So most of the use is at 25x, to frame huge objects like NGC7000 or the largest extensions of M31

chantepierre · 10 days ago

I'm sorry, I did not find what you meant by a 220 format frame. Is it a film photography type ?

dylan604 · 10 days ago

> cabinet makers were building the most impressive wood frames

You say impressive, but my mind reads that as heavy even if they looked amazing

hackingonempty · 10 days ago

You might be lucky enough that a local museum regularly hosts a telescope making workshop. In the SF Bay Area you can go to the Chabot Space & Science Center on Fridays 7-10pm.

helij · 10 days ago

https://stellafane.org/tm/index.html has good guides. There are astronomy forums such as CloudyNights with their own ATM sections. Edmind Optics has All About Telescopes by Sam Brown available online - https://www.edmundoptics.com/ViewDocument/All%20About%20Tele...

There are so many books around this and many great website such as this one for example: https://www.bbastrodesigns.com/tm.html

danilor · 10 days ago

I wanted to know as well! The resources I found, though, don't mention anything about what is the safety precautions one should take about the dust generated in the process. What masks to use and such. I understand everything should be done wet, but I wanted to know, for example, if one should wear a mask when polishing with cerium oxide even when wet. Maybe I'm being too cautions of this? I do fear what I don't understand! It's hard to make decisions without numbers. If anyone has any info on this please let me know! :)

hebrox · 10 days ago

I want to start looking at the sky with my kids. Would be nice to have something portable like the dwarflab mini. How would you rate it? Does it capture planets in some detail?

chantepierre · 10 days ago

Sadly not as I exclusively practice visual astronomy.

Here is a nebula, NGC7000, drawn by an excellent observer, which appears that way (very wide field, but a bit dimmer than their drawing) :

http://www.astrosurf.com/magnitude78/serge/images/NGC7000_10...

My advantage despite the low diameter is the ability to frame such huge objects !