Dobsonian Telescope Adds Plate Solver

March 16, 2023 by Bryan Cockfield 27 Comments

The amateur astronomy world got a tremendous boost during the 1960s when John Dobson invented what is now called the Dobsonian telescope. Made from commonly-sourced materials and mechanically much simpler than what was otherwise available at the time, the telescope dramatically reduced the barrier to entry for larger telescopes and also made them much more portable and inexpensive.

For all their perks, though, a major downside is increased complexity when building automatic tracking systems. [brickbots] went a different way when solving this problem, though: a plate solver.

Plate solving is a method by which the telescope’s field of view is compared to known star charts to determine what it’s currently looking at. Using a Raspberry Pi at the center of the build, the camera module pointed at the sky lets the small computer know exactly what it’s looking at, and the GPS system adds precise location data as well for a quick plate solving solution. A red-tinted screen finishes out the build and lets [brickbots] know exactly what the telescope is pointed towards at all times.

While this doesn’t fully automate or control the telescope like a tracking system would do, it’s much simpler to build a plate solver in this situation. That doesn’t mean it’s impossible to star hop with a telescope like this, though; alt-azimuth mounted telescopes like Dobsonians just need some extra equipment to get this job done. Here’s an example which controls a similar alt-azimuth telescope using an ESP32 and a few rotary encoders.

Portable Telescope Rolls Anywhere

April 5, 2021 by Bryan Cockfield 12 Comments

Since Galileo began observing celestial objects with a telescope, an almost uncountable number of improvements have been made to his designs and methods. Telescopes can now view anything from radio waves to gamma waves, come in a wide range of sizes and shapes, and some are also fairly accessible to hobbyists as well. In fact, several homemade telescopes are specifically designed for ease of use, portability, and minimum cost, like this portable ball telescope. (Google Translate from Italian)

The telescope was designed and built by [andrea console] and features a ball-shaped mount for the mirror which was built from a bowl. Ball designs like this are easier to orient than other telescopes since the ball allows for quick repositioning in any direction, but the main focus of this project was to investigate focal length with various accessories while also being as portable as possible. To that end, the mount for the eyepiece is on a lattice that assembles and disassembles quickly, and the ball and other equipment are easily packed. This makes transportation quick and easy and reduces weight compared to a more traditional, or even Dobsonian, telescope.

This build is impressive not just from having an extremely portable telescope, but also from [andrea console]’s documentation of the optics in his build. It includes some adjustable parts which can increase the magnification and has detailed notes on all of the finer points of its operation. The ball telescope is a popular build, and we’ve recently seen others made out of parts from IKEA as well.

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DIY Telescope Courtesy Of IKEA

March 12, 2021 by Bryan Cockfield 38 Comments

Some of the most expensive hobbies have some of the more ingenious hacks on display, generally to lower the cost of entry to various parts the hobby itself. Amateur astronomy has expensive, necessary equipment such as telescopes and other optics, but also has a large group of people willing to build their own gear out of some surprising materials rather than buy pre-built equipment.

One of the latest telescopes from [The Amateur Engineer] uses several bowls from IKEA to build the mirror mount. It’s a variation of a Portaball telescope, which is similar to a Dobsonian telescope except that it is much easier to adjust and point in any direction. This “Portabowl” telescope uses two bowls epoxied together and weighted at the bottom as the core of the build. The mirror mounts inside the ball, and some supports are attached to it to hold the eyepiece and mount. With some paint and some minor adjustments it’s ready to go stargazing.

There are a few improvements to this build planned for the future, such as the creation of a larger ball that will make operating the scope easier. All in all, though, it’s an excellent example of amateur astronomy even without needing to go as far as grinding one’s own mirrors.