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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Joined 2 years ago
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Cake day: July 20th, 2023

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  • I do a lot of focus stacking.

    Like, a lot. These days basically every one of the, erm, still life objects pictures that I post (okay, okay, knives) are stacked. The closer you get to your subject the shallower your depth of field becomes, and even with a pinhole aperture it’s often impossible to get all of an object into focus in one go.

    I will say this about that: I do all of my stacking outboard, not in my camera. That’s because my Canon R10’s inbuilt focus stacking (and bracketing) is profoundly stupid in both the way it produces results and how you have to operate it. I can deal with the clunky bracketing interface because I can set it up once and I leave it on all the time, or at least all the time I’m taking object photos.

    But if you don’t perfectly appease the camera’s built in algorithm and ensure that all of your frames have at least something with sharp enough contrast on it for the camera to decide it’s “in focus,” it throws a hissy fit and produces an error message, and deletes the entire stack of photos it already took. You can’t specify the range to bracket through in any real world units, only in arbitrary steps of “less” or “more,” and then you get to guess how many steps the camera should do. You don’t get to try again with the images or a subset of the images it’s already taken. Ye gods forbid you undershoot – not all of your object will be in focus, so do it again, stupid – or overshoot – hissy fit error message, see above. You don’t get to tune which shots are included in the stack and which aren’t, and it makes dumb compositing decisions that tend to result in putting hazy, fuzzy clouds around edges that should otherwise have been in focus and doesn’t deal with reflective objects in any meaningful capacity at all.

    The best way I’ve seen it implemented from a UI perspective is how Open Camera on Android does it, which allows you to set a specific focus depth for the start and end of your stack, and then you specify how many photos to take in the middle. It evenly divides the automatic focus adjustments between that range. You get a preview of each focus depth as you mess with the sliders, so you can ensure that the range is actually where you want it without having to guess. This is fast, easy, and intuitive, and you don’t have to dig through any submenus to make it do what you want.

    So what I do instead with my R10 is take an absurd number of shots with tiny steps, and deliberately both under- and over-shoot the focus range, typically from an inch or so in front of my subject all the way out to infinity. I use Helicon Focus on my PC which seems to give me the best results with a minimum of having to fight the user interface, and I simply discard the shots that are outside of usable range. Using this method you can also intentionally exclude images that actually were in focus but you’d still like not to be in your final picture, while still maintaining a greater depth of field than any single photograph could have provided. Helicon seems to do a pretty decent job of not making this look natural and not like an uncanny Blender rendering, or something.

    The bad news is that Helicon is not cheap. The good news is, you can always fly your Jolly Roger and lay your hands on a copy of it anyway.



  • I’ve never seen naptha (i.e. Zippo lighter fluid) do anything to any painted or finished surface, nor any of the plastics I’ve ever tired it on. I’ve been using the stuff in that context for decades, to the extent that I literally purchase it by the gallon. (I also use it in my lighters, because painter’s naptha is like 2% of the cost per volume of brand name Zippo fluid despite being the same stuff.)

    WD-40 contains nonvolatile oils that will leave a difficult to clean off residue behind and if you use it on anything porous it will soak in and possibly stain the surface while being functionally impossible to remove without using yet more solvents. For that reason it’s not really a great way to get stickers off of things, especially things that you’d like to remain non-greasy or may need to stick something to again at some point in the future (paint, tape, etc.).

    Naptha will evaporate entirely on its own given enough time, and you can even use it on paper and printed surfaces (excluding inkjet printed things, in my experience, which it will smear) with no harm done after it fully dries.



  • I personally do not trust ISP provided routers to be secure and up to date, nor free of purposefully built in back doors for either tech support or surveillance purposes (or both). You can expect patches and updates on those somewhere on the timescale between late and never.

    Therefore I always put those straight into bridge mode and serve my network with my own router, which I can trust and control. Bad actors (or David from the ISP help desk) may be able to have their way with my ISP router, but all that will let them do is talk to my own router, which will then summarily invite them to fuck off.

    Likewise, I would not be keen on using an ISP provided router’s inbuilt VPN capability, which is probably limited to plain old PTPP – it has been on all of the examples I’ve touched so far – and thus should not be treated as secure.

    You can configure an OpenWRT based router to act as an L2TP/IPSec gateway to provide VPN access on your network without the need for any additional hardware. It’s kind of a faff at the moment and requires manually installing packages and editing config files, but it can be done.


  • You don’t necessarily have to stop your aperture down that far, but I suspect you should be able to use a much shorter shutter time. That’ll cut down your overexposure and possibly also help with the color fringing around the edges.

    There will be a sweet spot of aperture for your lens where the sharpness and chromatic aberration (color fringing) are at their minimum. This is unlikely to be at the extreme open end (low ƒ number) or far down into the extreme closed end (high ƒ number). You can experiment to find where this is for your particular lens, though. The beauty of shooting digital is that film is free and you can review your results right away.

    ƒ-16 was probably actually too small an aperture for my shot, but it worked well enough.


  • Moooooon!

    Before I get into the usual kibitzing-on-the-internet thing: Great shot!

    Something to bear in mind about the moon specifically is that you can throw away most of your astrophography habits, and along with all of their damned complexity.

    The moon can be shot at using exposure settings pretty close to what you’d use for sunlit terrestrial scenes. That’s because the moon is… lit by direct sunlight.

    I took this one at 800mm using my telephoto extender, hand held (!) at ISO-100 and a mere 1/50 sec, and through a veritable pinhole of ƒ/16 because I was vainly attempting to get it as sharp as possible. Although come to think of it, extended that far I’m not sure my current lens can get much more open than that anyway. Whether or not I succeeded at this is up for debate, but as long as your arms don’t get tired holding up your camera and lens you can use a short enough exposure to leave your tripod and remote release and all behind.


  • PC operating systems are, at least to a broad degree, generic. That’s because a huge amount of backwards compatibility is built right into the PC architecture, much to the delight or chagrin of everybody depending on who you ask. There’s silicon on your processor’s die right now that’s doing fuck-all except ensuring that if you were struck by the perverse urge, you could boot MS-DOS 1.0 onto it even though it’s virtually guaranteed that you never will.

    Phone operating systems absolutely are not generic, because each phone model is basically unique unto itself in terms of what hardware is in it, and backwards compatibility is not in any way a design goal. Furthermore, the entire package has to be rolled into a single unified ROM image.

    There are proprietary core components in phones, notably their SoCs (systems-on-a-chip) and modems (which are often built into the SoC) which their designers jealously guard and are loaded down with patents and other IP restrictions. This hardware requires closed source drivers which must be updated or at the very least recompiled for new kernel versions if the OS is to be updated. That’s for Android, anyhow. It’s even worse for Apple devices, because they’re entirely closed and Apple is in total control of both the hardware and the software. At least they bother to support their own devices with updates for quite some time, but even they’re not absolved of fuckery – see, for instance, the deliberate slowing-down-with-updates scandal from a few years ago.

    If nobody is providing source code or compatible binaries for the core hardware your phone needs in order to work, at minimum it’s going to be impossible to update your device beyond the kernel version that was last supported on it, even with a custom ROM. And all of this is before getting into locked bootloaders and other chicanery that prevents you from running your own code outside of user space on the hardware even if you had the code to run.

    At the end of the day: The hardware vendors are absolutely not interested in providing driver support to end users or source code to anyone, and the handset makers and most especially the cell service carriers, at least in the US where the majority of people buy or lease their phones from said carriers, literally have a vested interest in dropping support as soon as they can get away with it. That’s because rolling out updates to oodles of individual phone models costs money to do, but they only make more money off of you by selling you a new phone.



  • Former professional driver here (and current avid rider of motorcycles):

    Driving absolutely isn’t for everyone. Some people can’t drive. Some people – arguably a lot more people than is currently the norm – shouldn’t. And that’s okay.

    If at the end of the day you can get to where you need to go regularly without driving, go for it. Nobody should be pressuring you into driving if you are not comfortable or prepared to do so. It’s not a “basic skill.” It’s a massive privilege, and one that most of the population of the world does not have access to. And it’s also a big responsibility with the potential, as you have observed, for injury or death of yourself or others, and property damage. That’s a responsibility that has to be taken seriously and the maddening fact is that most people don’t treat it with the respect that it’s due.

    If you don’t want to drive, don’t. And don’t let other people try to dictate that you should. Or if you want to get back to it later, other people don’t get to dictate your own timeline for that for you.



  • I’ll echo the GPD sentiment already on display here. I have a GPD Win Max 2 and it’s not exactly pocket sized per se, but it is just about as small as you can make a traditionally laid out (more or less) laptop while still keeping it usable. It’s also tiny little gaming monster which is neat, but might be overkill for purposes. I carry it around in a pistol case rather than a laptop bag, just to be an asshole.

    If you want to go smaller you can try the GPD Micro PC which is roughly the volume of an OG Nintendo DS although its proportions are a little different.

    If you want cheaper and don’t need the horsepower, one of my coworkers actually bought one of those little N100 based 8" micro laptop thingies, akin to this one, and I have some hands on experience with it. They’re sold under a myriad of non-brand names and I believe internally they’re all the same. It’s got about the footprint of a paperback novel although it’s much thinner, and could conceivably be put in a pocket if you wear Jncos, or possibly in a jacket. I was surprised at the build quality but the performance is rather dire, and using its little capacitive mouse nubbin for any length of time is an exercise in frustration.

    All of these are truly x86 compatible, i.e. real computers, and come with Windows by default. They can certainly be bullied into running some flavor of Linux if that’s what you prefer.