Time before sunset left

This is the old boy scout method of determining the time left until the sunset (or elapsed after the sunrise) "manually".

And here is how I have it criticized for my backpacking group folks:

5 Watt flashlight conversion for $5

It's not really for astronomy use but the flashlight goes into my travel duffel. A 5 watt LED star can be easily installed into this cheap diving flashlight and powered by 14500 LiPO cells at 7.4 Volt and 2400 mAh.

Mor details under the cut.

Meade ETX125 easy collimation

I have noticed that my ETX125 airy disk developed two hot spots which mean it got out of collimation a bit.

My favorite for eons Weasner website has a lot of information on that but it's mostly "don't do that yourself", "be super careful", and very little on the actual subject with quite a conflicting tips. So here is how I've done it:

What to do on a cloudy night? Or Star Chart VR!

Deprivation after just a handful of cloudy observing nights leads to... ideas. I have borrowed my Son's Gear VR headset and found a pleasant virtual world of astronomical wonders immediately surrounded me almost naturally.



StarChart is a simplistic amusement app, but the digital implementation of the starry night ambience is truly artistic. It even has its own darkness-adaptation-safe campfire! Wonderful touch. No images spoiling under the cut as the immersion is the key.

Laser collimator external power mod 2

Just a bit over a year passed since the previous emergency mod I did to my laser collimator. It's been serving me so well after that the version 2 has been postponed until I had to print something small to test the new printing bed.

The construction design is very simple and based around the micro USB PCB I've got off eBay for like $0.75 a pair. It went out very nicely overall and works flawlessly. Goodbye "pill" batteries.

Planisphere Android Widget

For several years I've been looking with envy at the Android Smart Watch custom clock face with that simple planisphere on it and wanted something like that on my phone screen as well. I thought it's obvious to port the wearable screen to the regular one and had been waiting for a couple of years for that to happen... No luck. But finally, the wait is over.

I had some time this spring to implement it! Looks gorgeous between my other informational widgets, which I am consulting with several times a day:

Cheshire Eyepiece

The Cheshire eyepiece is the simplest telescope collimation device. There are plenty of makeshift solutions, like the film canister with the hole in the cap, but the best guide for making a decent one along with all the underlying theory can be found here. One day I've decided to shim my Astroscan front glass to improve the collimation and 3D printed my own Cheshire.

The construction looks very simple, but there are several important features making the collimation and the printing easier.