Rick's b.log - 2023/04/02 |
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It is the 21st of November 2024 You are 18.188.223.120, pleased to meet you! |
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In this video, you can see a few interesting things:
Night falls slightly sooner with the camera as its low light response . . . was probably impressive in 2005. ☺ But it's actually not that much difference in speed for us humans, just a little later as our eyes have a secret weapon (switching from cones to rods) which helps with low light vision.
Another thing that I find interesting in these time lapse recordings is how fast the shadows dance. I know, when I'm outside, that the sun moves. But it's more a sort of "it's up there (beat) it's over there". Looking at the shadows, I feel like I ought to be able to look up and literally watch the thing moving.
We looked at each other as he kept on hopping around the windowsill. After examining it in detail, one eye on me, he decided there was nothing of interest here, turned directly to face me for a moment, then flew away.
Otherwise, it was a peaceful holiday. I sat out on the sunny warm days, had to go fetch a parcel because the carrier couldn't be bothered, saw the first swallow, drove the longest distance I've gone yet to get my car seen to (and know that I can do it again for the major service), and wrote firmware for a time lapse camera (as I'm sure you've noticed ☺). So it's not been a wasted week. Just... a week that passed all too quickly.
Back to the grind tomorrow. Pfffffft.
A longer time lapse
I reduced the image size to SXGA (1280×1024), and knocked the quality back a little (to 10). This meant the average file sizes were somewhere between 160-210K, which allowed me to capture 600 photos (or ten hours of time lapse).
Don't do that, by the way. Looking at the sun is not good for the eyeballs. Blown pixels can't be replaced.
Oh, hello.
As I was writing this, somebody came to say hello.
Hello, Wagtail.
I only got that quick photo over the back of my monitor as I didn't want to scare him away with sudden or threatening movements. Perhaps that explains the final gesture, a sort of "thanks for being cool about this"?
The end of my little holiday
Well, I barely got anything done in the garden. They're still protesting about the pension changes and the government is still planning to press ahead with it. They requisitioned the oil refinery workers to go back and do their jobs, I think it's going through the court now (or soon) to determine if that was constitutional.
There is fuel, there's just not a lot of it, especially for those using petrol. Which means still a ban on jerricans, which means no petrol to put into the mower.
I did a quick cut of the grass on the Saturday before last (25th March), it needs doing again!
Zerosquare, 3rd April 2023, 21:16 Can you set the camera's exposure and white balance manually? I believe it would eliminate (or at least reduce) the "strobe light" effect and make the timelapse look smoother.
For extra credit, implement your own auto-exposure/auto-white balancing algorithm, but with smoothing over a longer time period (say, minutes instead of seconds) :)Rick, 3rd April 2023, 22:28 Not normally. There might be a way using the internal registers, but the only available datasheet is a preliminary one lacking details, and my SDK is too old for direct register access.
I'm not sure that it would work, either, to leave the thing on all the time and not power down between shots, as the camera usually runs fully automatic and as such can change between two shots taken at the same time if the ambient (sun goes behind a cloud, say) changes.
I think it would be nifty to do an algorithm to sort out the pictures, however that sort of maths is way above me...David Pilling, 5th April 2023, 13:34 Brings ideas to mind, not that it would be worth doing any of them.
Could take multiple exposures at each time and select suitable brightness in post processing.
Could post process to even out brightness.
Could look at overall brightness of an image - just sum all the pixel values and then decide whether to take another one with a different exposure setting.
Can assume that any pixel of 254 or more is over exposed and any of 1 or zero is under exposed.
Existing software. As with focus stacking which glues together photos based on different bits being in focus there is software which takes photos with different exposures and makes an enhanced image. Exposure blending.
Useful applications - watching the water level in the well, or how cloudy the sky is.
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