dual_sport_dork 🐧🗡️

Progenitor of the Weird Knife Wednesday feature column. Is “column” the right word? Anyway, apparently I also coined the Very Specific Object nomenclature now sporadically used in the 3D printing community. Yeah, that was me. This must be how Cory Doctorow feels all the time these days.

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Cake day: July 20th, 2023

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  • 𝒯𝒽𝒾𝓃ℊ𝓈 𝓉ℴ 𝒹ℴ 𝓉ℴ𝒹𝒶𝓎:

    • ℋℴ𝓃𝓀
    • 𝒟𝓇𝒾𝒻𝓉 𝒾𝓃𝒸ℯ𝓈𝓈𝒶𝓃𝓉𝓁𝓎 ℴ𝓊𝓉 ℴ𝒻 𝓉𝒽ℯ 𝒹ℯ𝓅𝓉𝒽 ℴ𝒻 𝒻𝒾ℯ𝓁𝒹
    • 𝒮𝓊𝓈𝓅𝒾𝒸𝒾ℴ𝓊𝓈 𝓈𝒾𝒹ℯ-ℯ𝓎ℯ
    • 𝒫ℯ𝒸𝓀 𝒶𝓉 𝓉𝒽ℯ 𝓅𝒽ℴ𝓉ℴℊ𝓇𝒶𝓅𝒽ℯ𝓇’𝓈 𝒷𝒶ℊ 𝓈𝓉𝓇𝒶𝓅 𝒶𝓃𝒹 𝓇𝓊𝓃 𝒶𝓌𝒶𝓎
    • 𝒪𝓃𝓁𝓎 𝒹ℴ 𝒶𝓃𝓎𝓉𝒽𝒾𝓃ℊ 𝒾𝓃𝓉ℯ𝓇ℯ𝓈𝓉𝒾𝓃ℊ 𝓌𝒽ℯ𝓃 𝓉𝒽ℯ 𝒸𝒶𝓂ℯ𝓇𝒶 𝒾𝓈 𝓅ℴ𝒾𝓃𝓉ℯ𝒹 𝒶𝓉 𝓈ℴ𝓂ℯℴ𝓃ℯ ℯ𝓁𝓈ℯ

    …𝒜𝓃𝒹 𝒹ℴ 𝒾𝓉 𝒶𝓁𝓁 𝒷ℯ𝒻ℴ𝓇ℯ 𝓉𝒽ℯ 𝓉ℴ𝓌𝓃 𝒸𝓁ℴ𝒸𝓀 𝓉ℴ𝓁𝓁𝓈.




  • This is probably a poster child for an HDR photo: A large disparity between the highs and lows, stationary subjects, and most of it probably beyond the hyperfocal distance.

    Poke around in your camera’s settings and you may find the option. It probably has it built in, but in the unlikely even it doesn’t you can still brute force it by exposure bracketing manually (i.e. take a couple of shots of the same thing at bright/medium/dark exposure levels via fiddling with your shutter speed) and smash the resulting photos together on your computer in software, e.g. HDRMerge or similar.





  • It’s the same line of logic as when you see people post on a forum something like [img]c:\Users\Bob\Documents\My_Image.bmp[/img] and then wonder why it doesn’t work.

    “But I can see it on my computer!”

    Over the internet, the origin of all data is on someone else’s computer. All means all. And all of it needs to come down the wire to you at some point.

    You’re on the right track in one regard, though, in a roundabout way with caching: Browsers will keep local copies of media or even the entire content of webpages on disk for some period of time, and refer to those files when the page is visited again without redownloading the data. This is especially useful for images that appear in multiple places on a website, like header and logo graphics, etc.

    This can actually become a problem if an image is updated on the server’s side, but your browser is not smart enough to figure this out. It will blithely show the old image it has in its cache, which is now outdated. (If you force refresh a webpage by holding shift when you refresh or press F5 in all of the current modern browsers, you’ll get a reload while explicitly ignoring any files already in the cache and all the images and content will be fully redownloaded, and that’s how you get around this if it happens to you.)








  • The Hubble is also in a rather low Earth orbit (340-ish miles), which enables it to use magnetic brakes which allow it to ditch the excess energy from its reaction wheels into the Earth’s magnetic field so it can stop pivoting when it aims. The further away you get from the planet the less effective that becomes. The bigger your object is, the bigger your reaction mass needs to be.

    And the Hubble doesn’t inherently roast or blind innocent bystanders as it swings its point of aim across all of the intervening space between its targets. Maintaining a steady shine on one particular point on the surface is one thing, but these idiots seem to be implying that they will sell sunlight-as-a-service via some kind of subscription model to multiple customers, so they would presumably be changing targets all the time.

    The Hubble can only rotate very slowly. Per the article, 90 degrees in about fifteen minutes. Its advantage is that it only looks at targets that are very far away and hold still relative to the Earth, so there is very little parallax to worry about. If you wanted to go faster you probably can’t use the reaction wheel method that it does; you’d have to use thrusters which would consume finite fuel that’d eventually (or quickly) run out, and at that rate there’s no way you could do it as accurately. For the Hubble specifically, the amount of time it takes to get on a target is broadly irrelevant, only that it can keep itself there once it eventually achieves targeting. This would not be so with the hypothetical solar reflectors, regardless of what altitude they were flown at. And low altitude orbits would be the worst, because they’d be flying over the target’s head at tens of thousands of miles per hour in terms of ground speed and would have to rotate very quickly in order to remain even vaguely pointed in the right direction.