title: Garmin watch faces
author: cjhandmer
contenttype: article
publication: Casey Handmer's blog
published: 2026-03-13T19:50:06+00:00
sourceurl: https://caseyhandmer.wordpress.com/2026/03/13/garmin-watch-faces/
word_count: 691
I have recently been using Claude Code (Opus 4.6) to do a variety of software projects. One was the completion of an ill-fated attempt to create a custom watch face for my Garmin Epix Pro 47 mm. MidJourney produced this conceptual image for me, which is what I was trying to capture. I wanted azurite/malachite/copper colors, and hands for astronomical details. This would be almost impossible with a physical watch but pretty easy if you have a small screen to work with. For reference, this is the mineral in question. I was ultimately able to get something like this working. Here we have a sun and moon hand that show location both over the Earth’s surface and in the sky with respect to two overlaid polar-projected maps. Hours in Roman numerals, and the sun hand revolves once per day. The Moon hand shows phases and both hands show eclipses when they occur. Gold, silver, and purple curves give the terminator/horizons for the sun, moon, and user respectively. With this you can easily deduce who can see which body and whether and when it will be day time. The background shows the brightest stars which rotate in sidereal time. This turned out to be so much fun that I designed a few more. This one shows time on Mars, with a background map showing shaded topo relief of the planet (there are no shorelines at present), and stars. The user’s location is given as the Phlegra Montes, one potential site for a base. The white patch to the left is the Tharsis massif. The dark patch to the right is Hellas. We have a sun hand, and Earth hand, and two moon hands. The red one is phobos and turns anti-clockwise, matching its real world behavior. The hour dial includes N (nulla) to mark the 39 minute leap hour to account for Mars’ slightly slower rotation than Earth. During the time slip, the minute hand splits. NASA uses a different convention with “Mars hours” etc that are a bit longer than Earth hours, but that’s not as fun for watch design. Because Phlegra Montes is the first landing site, its timeslip is around midnight. Other locations on Mars experience the time slip at different times. Returning to Earth, I wanted something a bit less abstract. This one was quite hard to get right, requiring some manual coding (shocking!) It has a sun hand, moon hand, minute and second hand as before. The face is oriented such that the sun is at its zenith over the user at noon in their respective time zone. The lit side of Earth is the “pale blue dot” image, while the night side shows city lights. The terminator is orange to mark the sunset/sunrise. Finally, for completeness, the Moon. For this one I went a bit minimalist. The face shows a shaded relief map of the lunar south pole out to 80 degrees south. Blue marks the permanently shaded regions where ice may be found. Red marks the hills and slopes from which Earth is visible and vice versa. IMHO, a base should be built here so we can see its lights from Earth. The Moon rotates about once a month so I have a sun on the rim showing its location relative to the pole, and a shaded ring showing the light side of the horizon vs the dark. The relief is shaded in accordance with the solar position. At the noon position, we have a complication showing the appearance of the Earth from the Lunar south pole at that time. Phase, rotation state. During lunar eclipses, its blue atmosphere turns red. In the shot above, the middle east and eastern africa are visible around their dawn – they are shown south up, as would be seen from the lunar south pole. The time is shown with three hands depending from the rim in the conventional manner. If you would like to try these for yourself, I have the latest .prg files collected here . No warranty, no guarantees, etc. These are vibe-coded and free! Let me know if you’ve made any cool custom watch faces!