This is 6/21 (solstice!), 6/26, 6/27, and 6/28. The daily solargraph pipeline is working pretty well now, and I've finally figured out the stitching to make a smooth sun trail. These are each the last shot of the day with the sun trail overlaid.
I'm working on a web page that will let you browse all the daily solargraphs as they happen (well, with a day delay obviously), so stay tuned!
Happy Solstice! I've made a solargraph simulator that lets you draw solargraphs from 20 different locations on the planet. In addition to picking the place you want to view the sky, you can animate the solargraph, draw just one point per hour for the analemma view, pick the season, and there's even a panorama mode that projects the solargraph into a virtual sky that you can look around with the mouse.
Check it out and let me know what you think!
Continuing my digital solargraphy experiments, here's a little animation I put together from yesterday's captures. This is combining the composited sun path taken with underexposed shots on top of bright frames at normal exposure every 30 minutes (or so, I missed a couple early in the day).
Watch until the end to see who wins 😅
Maybe not much new here for this crowd, but figured I'd share. I've got a few more solargraph-related things coming soon…
This is ,ostly to show that the weird kink in my previous posting was a stitching mistake (somebody mixed up which camera is which…). The second image is the real composite of all of today's shots, taken with my standard underexposure settings (10-stop ND filter, 1/2000s at ISO 100, if you're interested). But I also take calibration shots with normal settings every full hour, so I figured I might as well try overlaying the composited sun path on one of those. Looks kind of interesting.
The bright straight line on the right is an awning we had partially out today, sorry :) It won't be in the longer-term shots, because the cameras will be mounted higher up.
There's still a little bit of roughness in the stitching area, but we're getting closer…
This comes with a lot of asterisks, but it shows that it can be done :D You're looking at a solargraph stitched together from 2x750 photos taken at one-minute intervals with two GoPro cameras over the course of a day. The stitching isn't quite perfect as you can see, but I've solved a lot of issues already.
EDIT: seems Reddit doesn't like a lot of near-black in images and decided to compress and brighten it up a lot? Not sure what that's about, but the noisy light gray stuff isn't supposed to be there…
I have scripts that control the GoPros to start capture in the morning and stop at night, as well as download the images. I have an image processing pipeline that performs some noise reduction (more to come), stitches the images together, and then blends them into one image per day. Later I will blend all the days together into one image (and make some animations).
Even just the stitching was not without its challenges thanks to the GoPro's fisheye optics. I also had to find a projection of the stitched image that let me have a level(ish) horizon without distorting the sun disk. There's more work to be done, but this shows that the basic setup works.
The second image is zoomed in and the exposure reduced to show you a bit more of the data. The composite is about 10,000 pixels wide and there's tons of dynamic range. You can see the sun disks in the second image. At one-minute intervals, they overlap quite a bit. I might reduce the interval to two minutes to make this more manageable and still get a decent, continuous streak.
Anyway, just wanted to share this and get people's reactions. Let me know what you think!
We live on top of a ravine, which among other things is home to a couple (or more?) raccoon families. One day last June, we noticed the crows going crazy. The reason turned out to be that one of the raccoons had climbed one of the cherry trees and was eating cherries. I got a few decent shots…
I'm working on creating a digital solargraph and wanted to see if anybody has tried this before. There are still many things to be figured out, but the general idea is to take time lapses with a GoPro camera, and then combine them to look somewhat like an analog solargraph. But in addition, it'll make it possible to create animations, or recreate this clever analemma image somebody posted here a while ago.
I'm specifically looking at GoPros because they're obviously rugged, but also seem to have the best support for being controlled by scripts from a Raspberry Pi. I'm getting a 10-stop ND filter too, and will be experimenting with exposure to get an image that will be very dark, and have a sun disk that's as small as possible. I'll then figure out the processing to combine the individual images into a final composite (about 130,000 solstice to solstice at 1-minute intervals).
I'm just in the process of acquiring a bunch of stuff for this, and will do some experiments over the coming days and weeks. If things look promising enough, I'll then start the main capture at (or before) the summer solstice.
So I'm mostly posting to see if anybody would find this interesting, and if anybody has done this before – or if only analog/pinhole photography is allowed here :) (in my defense, I have a pinhole camera and actually took a long-exposure picture of a lunar eclipse many, uh, moons ago).