Telescope Building with John Dobson
Why Hacker News recommends it
Recommended to anyone interested in telescope making as a guide from Dobson himself.
What it is
A roughly 90-minute film of John Dobson building a Dobsonian telescope step by step, including hand-grinding the mirror.
Recommended by 4 HN commenters across 4 different months, 2017 to 2025.
What Hacker News said
Recommends danbruc · 2017-03 · on “Mirror grinding”
There is also a 90 minutes film »Telescope building with John Dobson« [1], inventor of the Dobsonian telescope [2], going through the entire process of building a 16" telescope from scratch. [1] [this video] [2] [LINK]
Recommends DanBC · 2020-04 · on “Hand Scraping a Truly Flat Plane (1908) [pdf]”
I like this video from John Dobson about handmade telescopes, where he builds a complete telescope including hand grinding the mirrors. [this video]
Recommends Prey4Jesus · 2021-02 · on “Ask HN: What entry-level telescope should I choose?”
The most important thing to look for is the diameter of the aperture. Your resolution is proportional to the diameter of the telescope (absent atmospheric conditions). I would recommend a minimum of 6" in diameter. 8-12" is preferred. With this in mind, the best telescope you can get for the price is a Dobsonian. Dobsonians are extremely mechanically and optically simple. This makes them long, and bulky. It also makes them cheap. It also makes them rather easy to point. They have a lot of mass and inertia, and a large moment of inertia. This makes them easy to move and point slowly and carefully. Dobsonians are ideal beginner telescopes. Easy to point, cheap, good resolution. This is the mod
Recommends nvalis · 2025-03 · on “Amateur Telescope Making Main Page”
There is a very detailed video documentation [0] about telescope building techniques, featuring insights from John Dobson, the inventor of the Dobsonian telescope mentioned on the page. [0] [this video]
Cites joshvm · 2023-02 · on “Online Lens/Optics Simulator”
I'm not sure if it will necessarily be cheap, maybe cheaper than an off the shelf mirror of equivalent size. This is what John Dobson (of the Dobsonian) is famous for. However you still need to do stuff like coat the primary mirror once it's polished and you can't easily do that at home. See [this video]