Wallace the 6 inch f/2.8 telescope, building it, and hiking with it

Wallace the 6 inch f/2.8 telescope, building it, and hiking with it(lucassifoni.info)

56 points by chantepierre 3 days ago | 6 comments

zonkerdonker 32 minutes ago |

Very cool project and video documentation, really inspiring! As someone who is mechanically inclined and has a decent amount of tools/3D printer, is there any DIY telescope that you would recommend to build as a first foray into the field?

I've never done much with optics, and after reading through a few of your posts, it looks both incredibly challenging and very rewarding.

chantepierre 22 minutes 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.

rom16384 24 minutes ago |

Quite an impressive build. How hard is it to collimate the telescope? Does it hold the collimation?

chantepierre 19 minutes 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

hackingonempty 2 hours ago |

Very nice!!

What are you using for interferometry?

chantepierre 38 minutes 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.