This Python conference presentation from over a decade ago includes an adjustment of such a visualization for DST which I think of often https://www.slideshare.net/slideshow/observational-science-w...
Combining 15s interval whole-sky-camera photos to form a 4y spanning keogram
51–60 of 93 posts
Re: Combining 15s interval whole-sky-camera photos to form a 4y spanning keogram
#52My favorite work in this vein is still the guy who did the trigonometry to convert a year+ worth of telemetry from a light level sensor in his back yard to paint a picture of the tree canopy. Each day is a scan line of light and dark patches at a different solar inclination. So everything above the sensor eventually got “painted”.
Re: Combining 15s interval whole-sky-camera photos to form a 4y spanning keogram
#53This Python conference presentation from over a decade ago includes an adjustment of such a visualization for DST which I think of often https://www.slideshare.net/slideshow/observational-science-w...
This site also has that view for a lot of places https://www.timeanddate.com/sun/usa/columbus
Re: Combining 15s interval whole-sky-camera photos to form a 4y spanning keogram
#54It took me a bit to understand that it's just the red line from the entire dome. It makes me a bit sad that so much information is discarded for these keograms. Isn't there a way to "peel" the image in such a way that the entire image ends up being the line? Like spiraling or something like that from the outer "rim" to the center point. Nevertheless, it's the first time I've seen this and liked the project a lot. I'v…
The goal of the keogram is to give a quick overview of sky conditions so you can see if there were clouds, aurora, or other interesting activity. No information is discarded, as the user keeps all of the data, the keogram is just a way of identifying which pictures might have something interesting.
The year long keogram presents even less data, as it's just the centerline of the keogram for each day. So, essentially just the center pixel of each image. Still gives a good overview of what the sky conditions were like throughout the year.
Re: Combining 15s interval whole-sky-camera photos to form a 4y spanning keogram
#55I did much the same thing (and much more) 10 years ago. I used a RPi as well as a Canon point-and-shot out my window. My pics were 1 per minute.
Here is a link to the keogram section (I didn't know the term), but watch the whole video, I did a bunch of other art:
Re: Combining 15s interval whole-sky-camera photos to form a 4y spanning keogram
#56I generate these type of charts [1] focused on the daylight hours so it was a surprise to see a concave shape instead of a convex one. Awesome way to validate these computer generated charts with captured physical data. [1] https://shademap.app/@52.39941,4.88468,11.49849z,17360064872...
This is really neat. I'm curious where the data for the tree shadows comes from though. I was surprised to see that the trees in my yard and my neighbor's yard were all mapped by your service, since I live in a small town in the middle of nowhere. I read the "how it works" FAQ section, which explained that building shadows come from the map services, but it didn't mention trees.
You can train ML to recognize vegetation in satellite photos and further train it to estimate its height +/-3 meters
Re: Combining 15s interval whole-sky-camera photos to form a 4y spanning keogram
#57Earlier quoted context omitted.
This is something I mention to the younger kids at start parties. Way back then, there was no internet, no devices, no tv, no radio, no movies, and more importantly no easily accessible calendars. You couldn't help but look up at the night sky. There was really nothing else to do, and when the only thing available to know when to plant and harvest was based on the constellations visible at the time. It helps put thin…
> There was really nothing else to do Well, nothing to do except for storytelling, music, dancing, parties, games, plays, sports, eating, drinking, visiting, festivals, gossip... People have been pretty good at keeping themselves entertained for a very long time.
And exactly how does that help the specific narrative?
Re: Combining 15s interval whole-sky-camera photos to form a 4y spanning keogram
#58My favorite work in this vein is still the guy who did the trigonometry to convert a year+ worth of telemetry from a light level sensor in his back yard to paint a picture of the tree canopy. Each day is a scan line of light and dark patches at a different solar inclination. So everything above the sensor eventually got “painted”.
Have you got a link or do you remember the name of this person?
Re: Combining 15s interval whole-sky-camera photos to form a 4y spanning keogram
#59Earlier quoted context omitted.
> There was really nothing else to do Well, nothing to do except for storytelling, music, dancing, parties, games, plays, sports, eating, drinking, visiting, festivals, gossip... People have been pretty good at keeping themselves entertained for a very long time.
And exactly how does that help the specific narrative?
You were writing as if people were staring at the sky all night long out of boredom. You said "There was really nothing else to do."
That's completely untrue. It's a total misunderstanding of what life was like.
I'm not helping your narrative, I'm saying it's a false narrative. We have so many misunderstandings about how people used to live, it's important not to perpetuate them.
Re: Combining 15s interval whole-sky-camera photos to form a 4y spanning keogram
#60You've got much better weather than we do. Here's mine from near Louisville KY (from Aug 2023 to Aug 2024) https://www.facebook.com/groups/101640086556073/posts/794426...
It's easy to forget how far north Europe is! The daytime vs nighttime hours is so much more extreme there. The Netherlands is on the same latitude as Newfoundland in Canada.
I noticed the extreme hour glass shape in his image, but it's even more impressive when compared to yours!