Latest posts
- Arp 114:May 30, 2026
North is left. (mirrored). 26x18 arcmin (0.3 arcsec/pixel) dt {color: var(--em-color)} Total exposure time:393 * 30 seconds = 3.2 hours. (across 2 nights) Exposure used in stack: 241 * 30 seconds = 2 hours. Telescope: C9.25 (230mm, f/10, fl=2300mm) Camera: IMX533 (16mm diagonal, square, color) Processing: (no software sharpening used) Callibration (dark + flats) Stacking (average w/ rejec
- Notes on optimizing battery life:May 27, 2026
Ok, so you have something with a battery, and you want it to run for a long time. First off, it helps to measure power draw in current and charge in well, charge. It is tempting to convert everything into power and energy, but don't. Even if you don't use any, most chips will use a few to generate internal voltages. This is the "typical" current draw of an AVR32DD32 microcontroller over volta
- Search engine results are truly terribleMay 15, 2026
A few months ago, I had the displeasure of trying to use the modern web without an ad-blocker. ad blocker ... obscure, but easy to find information: What is the lowest K-alpha emission energy of Molybdenum? ... and few normal(-ish) questions: What photodiode circuit should I use? How do airplane wings work? Why are brushed motors most efficient at high speeds? Asking a search engine questi
- Building a clock from salvaged Vacuum Fluorescent DisplaysMay 14, 2026
When was disassembling an old calculator (as you do) I found these cool VFD tubes: Normally, a whole display is built into a single flat package, which doesn't look particularly interesting. These ones have the individual digits inside a standard vacuum-tube housing, which gives them a cool nixie-esque look. Because vacuum tubes are rather archaic components, they deserve some introduction. T
- NGC 4236May 12, 2026
North is left, mirrored. 0.33 arcsec/pixel (16' by 11') dt {color: var(--em-color)} Total exposure time:457 * 30 seconds = 3.8 hours. Exposure used in stack: 187 * 30 seconds = 1.5 hours. Telescope: C9.25 (230mm aperture, f/10, fl=2300mm) Camera: IMX533 (16 mm diagonal, square, OSC) Processing: (no software sharpening used) Callibration (dark + flats) Stacking (average w/ rejection) White b