Building an equatorial mount for a Dobsonian-mounted telescope

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In this article series, I'm trying to build a working equatorial mount for a 10" Dobsonian telescope.

    Last summer, I was browsing Reddit as I oftentimes do on a slow Saturday afternoon, when I stumbled upon /r/astrophotography. It was probably some bestof'd post that led me there (maybe this one), but nevertheless I found myself soon after browsing /r/astronomy for tips on buying a telescope.

    When I get a (seemingly) great idea, I spend most of my waking time completely surrounding myself with it, until I face a setback and lose interest. Some years ago, I had a phase of absolute bonsai-mania. I read too many blog posts on growing those miniature trees, hung around on some obscure Finnish bonsai forum, and even attempted to grow a Sequoia tree from a seedling. When I noticed how slow everything was progressing, and when my Sequoia sapling surprisingly died in the snow (oops), I lost my interest almost as quickly as I had found it.

    In hindsight, I can say the same thing happened with my astronomy hobby last summer. I didn't research the subject enough, bought a telescope arguably too big for casual use, and when I didn't see the Hubble-y sights of distant galaxies and vibrant nebulae from our backyard, I gave up.

    Luckily, I had already invested enough money into the gear to feel that Sting of Bad Investment inside of me every time I saw the telescope sitting unused on our porch. I decided to restart my short-lived astronomy hobby, but I also decided to make a conscious effort to be patient and to control my greed for bigger and brighter views.

    I'm still very much a beginner in astronomy (discovered the Orion constellation just two days ago, after a month's hiatus from stargazing), and I've got no experience in hardware programming, let alone actually designing or building physical stuff. But here we are. I'm confident that with enough time and research, I will get at least some kind of working prototype done. Let's just hope that the time required is counted in months, not years!

    I actually did do some initial research a few weeks back, so I don't have to start empty-handed. I found this interesting article, which details the process of building an equatorial mount with an Arduino microcontroller. Fortunately I already have an unused Arduino Uno gathering dust on my table, so I am more than happy to use that for this project. The bad news is that the author of the article is building their mount for a camera, and I'm trying to build one for a 10-inch telescope. This means that I can't take the article's instructions on face value. I also measured the dimensions of the telescope, but I still need to figure out whether I want to go big and build a mini-observatory with a dome ceiling, or if I just want to complete the telescope mount.

    Here's a rough list of steps for the project:

    1. Decide whether to build mini-observatory or just mount - currently leaning towards observatory (I'd have a chair to sit on for my lazy ass).
    2. Sketch design, figure out how to build everything. This step is currently VERY vague. Gonna be its own post in the series.
    3. Buy plywood for mount - based on telescope dimensions should be at least 60cm x 60cm, but for observatory roughly 150cm x 150cm.
    4. Buy electronics required. This includes a stepper motor (not sure yet how powerful), a motor shield and components I don't even know I need yet.
    5. Build mount structure. I hope to work on this next weekend (16th - 17th of Jan).
    6. Connect electronics, write software. This is going to take multiple posts to complete.
    7. Fix problems, finalize.

    In the next post I will have the design sketched out, and I'll discuss more in detail what I'm planning to do.

    Building an equatorial mount for a Dobsonian telescope - Slow progress (Part 2)

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