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Joined 2 years ago
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Cake day: June 12th, 2023

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  • It was the 90s… rules were different then ! I still have my white pants deep in the closet somewhere… they haven’t seen the light of day in a while though :)

    I worked at Bell Labs back when this photo was taken - my office pretty much looked exactly like this, chair, furniture, Sun SPARCStation on the floor…

    Bjarne still rocks white pants sometimes to this day though ! And the same haircut - he really committed to the look :)



  • Didn’t the original full body scanners used at airports use backscatter X-rays, which are ionizing radiation ?

    I believe these were mostly replaced by millimeter-wave scanners, and are not used anymore (even banned in some countries) but a lot of the initial pushback and debate surrounding the scanners when they were first introduced was about potential health risks of repeated X-ray exposure from those scanners, and so the idea of ionizing radiation exposure persists to this day in many people’s minds.







  • photography might be an area where digital hasn’t caught up, since film’s resolution is down to the molecular level

    Film resolution is limited by the size of the silver halide crystals that make up the light sensitive layer of the film. Crystals can come in different sizes, but their sensitivity to light depends on their size - generally you need pretty large crystals for usable photographic film, somewhere between 0.1 and 10 microns (depending on the film ISO rating) - about 3-5 orders of magnitude larger than what you would consider molecular scale.

    When the film is developed the crystals are visible as film grain limiting the resolution in some ways similar to pixel size of a digital camera (although there are differences, since the crystal size is not completely uniform but rather has a specific distribution, creating a more random effect than the regular pixel grid of digital cameras)

    The pixel sizes on modern high resolution digital camera sensors are actually similar, down to 0.5 micron. It’s hard to make an exact comparison, but I have seen estimates that you need a full frame digital sensor of somewhere between 10 to 50 megapixels to equal the resolution of 35mm ISO 100 film.

    And modern sensors are much more light sensitive than film, which allows you to shoot more optimally and give you more flexibility (less exposure time, potentially higher f-stop with better lens resolution, lower ISO, less light, etc.) and therefore achieve potentially better results in more conditions. Add to that the hassle and costs of working with film, and most professional photo work is now done in digital as well. Film is generally only used for stylistic purposes, by purists who are not satisfied with digital simulation.











  • Pretty sure she is on a petrol one - there is a fuel tank above the front wheel, and you can see the fuel line going into the throttle body above the single piston engine. You can also see the exhaust and muffler below and behind the piston.

    Also looking into it more, I don’t think the Autoped was ever offered with an electric motor. Apparently the confusion comes from the fact that the company was bought out by the battery manufacturer Eveready, and sold as Eveready Autoped. Eveready modified the Autoped by adding a battery and ignition coil, replacing the original magneto system, but propulsion was always by means of a petrol engine.

    I don’t think the one in the photo has the battery and coil however - the coil can be seen here in front of the gas tank, but is missing in the OP photo.

    Edit: looks like the batteries and coil might have been separate - here is an article from 1917 that describes the Autoped as having a magneto ignition system (no coil) and also a battery box to operate the front and rear lights. And here is an example with an ignition coil powered from the wheel, but no battery box and no lights (which were probably optional) The one in the OP does appear to have the battery box and lights, but uses the magneto ignition, so it’s the same model as described in the article.


  • Fast film (you can see how grainy it is when you zoom in a little) and shooting in full bright sun = you can shoot very short exposure and freeze motion. There were already cameras in the 1930s with mechanical shutters that could do 1/500th and even 1/1000th of a second exposure, which is plenty fast for this type of shot.

    The lens looks pretty fast too - depth of field is very shallow, although part of that is also due to possible use of medium or large format - faster lens (lower f stop) and larger film both allow more light capture, and therefore faster exposure as well, but at the cost of less depth of field.

    Edit: here is a good print of the full frame - looks like ~1.50 ratio, so probably 35mm film (not medium or large format) - I can’t find a lot of information about what cameras Max Alpert used in the 30s, although he did use a 35mm Leica on at least some photos from that era. A Leica III could do 1/1000 in 1935 for example. The early Soviet cameras from the 1930s were also basically direct copies of Leicas. The frame also looks a bit underexposed, which could be due to pushing the exposure for more speed.