[Cole Price] describes himself as a photographer and a space nerd. We’ll give that to him since his web site clearly shows a love of cameras and a love of the NASA programs from the 1960s. [Cole] has painstakingly made replicas of cameras used in the space program including a Hasselblad 500C used on a Mercury flight and another Hasselblad used during Apollo 11. His work is on display in several venues — for example, the 500C is in the Carl Zeiss headquarters building.
[Cole’s] only made a detailed post about 500C and a teaser about the Apollo 11 camera. However, there’s a lot of detail about what NASA — and an RCA technician named [Red Williams] — did to get the camera space-ready.
“If you wish to make an apple pie from scratch, you must first invent the universe.” [Carl Sagan]. If you wish to make preserved lemons the same way as [Uri Tuchman], you have to start with that mentality. Video also below. The recipe for [Uri]’s preserved lemons involves two ingredients see sea salt, and sliced lemons, but we don’t expect you came here looking for a recipe and the food is less important than the journey.
Recipes take for granted that we have all the necessary utensils on hand, but what if you are missing one? What if you are missing all of them? Life’s lemons won’t get the best of us, and if we’re utensil-poor and tool-rich we will make those lemons regret trying to take a bite out of us. The first fixture for cutting lemons is a cutting board, then a knife, and finally an airtight container. We see him make all of them from stock material by hand. Does that seem like a lot of work? You forgot that if you’re going to eat up, you’ll need a serving platter and fork. If he ever opens a restaurant, don’t expect it to be fast food.
The photographic hire company Lensrentals had a $2k Sony FE 135mm f1.8 GM camera lens returned with a problem: it was having issues focusing. So, they decided to do the obvious thing and take it apart. It’s a fascinating insight into some of the engineering that goes into a high-end camera lens.
That is perhaps a rather scary thing to do, because this is a very new lens that doesn’t even have a service manual yet. That’s akin to rechipping a Ferrari when you’ve never even opened the hood before.
One of the interesting things inside is the presence of a number of shims that adjust the placement between the groups of lens elements. It seems that however good their manufacturing tolerances are, sometimes you just have to put a shim or two in there to align things.
[Dr. Suess] created memorable books with minimal words and bright artwork. He inspired children and adults alike, and one of them, [Len], grew up to create wind instruments for the Bellowphone channel on YouTube. Behind the whimsy of his creations is significant engineering, and this time, we get to see the construction of a fipple. The video is also shown after the break. Even though fipple sounds like a word [Dr. Suess] would have coined, it is a legitimate musical term that means a whistle-like mouthpiece. In this case, it blows air across glass jars to create the sound for [Len]’s bottle organ. Check out the second video below for a performance from The Magic Flute.
[Len] uses clear rigid PVC for the fipples and a custom forming die to shape them while they are soft. The rest is precision hand-tool work with a razor saw, hand file, and wet-dry sandpaper. Once complete, the fipple looks like any musical instrument part produced by exacting construction techniques. Making a mouthpiece is one thing, but if it is not directed correctly it will not make any sound, so we also learn how to turn steel strapping into an organ bottle assembly. If you add some tubing and rubber squeeze balls, you can make your own instrument.
Let’s say you’ve watched a few episodes of “The Joy of Painting” and you want your inner [Bob Ross] to break free. You get the requisite supplies for oil painting – don’t forget the alizarin crimson! – and start to apply paint to canvas, only to find your happy little trees are not so happy, and this whole painting thing is harder than it looks.
[Saint Bob] would certainly encourage you to stick with it, but if you have not the patience, a CNC painting robot might be a thing to build. The idea behind [John Opsahl]’s “If Then Paint” is not so much to be creative, but to replicate digital images in paint. Currently in the proof-of-concept phase, If Then Paint appears to have two main components: the paint management system, with syringe pumps to squeeze out different paints to achieve just the right color, and the applicator itself, a formidable six-axis device that supports tool changes by using different brushes chucked up into separate hand drill chucks. The extra axes at the head will allow control of how the brush is presented to the canvas, and also allow for cleaning the brush between colors. The videos below show two of the many ways [John] is exploring to clean the brushes, but sadly neither is as exciting as the correct [Bob Ross] method.
It looks like If Then Paint has a ways to go yet, but we’re impressed by some of the painting it has produced already. This is just the kind of project we like to see in the 2019 Hackaday Prize – thought out, great documentation, and a lot of fun.
At the top of the British electronic intelligence agency is the Government Communications Headquarters (GCHQ), a very public entity whose circular building can easily be found by any inquisitive soul prepared to drive just off the A40 in Cheltenham which is about two hours west of London. But due to the nature of its work it is also one of the most secretive of UK agencies, from which very little public information is released. With over a century of history behind it and with some truly groundbreaking inventions under its belt it is rumoured to maintain a clandestine technology museum that would rewrite a few history books and no doubt fascinate the Hackaday readership.
Perhaps the most famous of all its secrets was the wartime Colossus, the first all-electronic stored program digital computer, which took an unauthorised book in the 1970s to bring to public attention. Otherwise its historical artifacts have been tantalisingly out-of-reach, hinted at but never shown.
A temporary exhibition at the Science Museum in London then should be a must-visit for anyone with an interest in clandestine technology. Top Secret: From ciphers to cyber security occupies the basement gallery, and includes among other exhibits a fascinating selection of artifacts from the Government agency. On a trip to London I met up with a friend, and we went along to take a look.
Many a budding maker has experimented with invisible inks, with a wide variety of solutions having a viable set of properties for this purpose. However, [Ben Krasnow] stumbled upon a different method entirely when tinkering with a UV laser.
The laser in question was a MNL100 UV laser, configured to produce nanosecond-scale 20 kW pulses at up to 24 Hz, operating at wavelength of 337 nm, deep in the ultraviolet. After piping the laser light through an optical fiber and aiming it at some regular white paper, dark marks were observed, which disappear without a trace over the course of a few minutes.
Upon investigation, the dark marks seemed to be the result of fluorescent whitening agents in the paper. It appears they are overloaded or otherwise changed chemically by the laser, and slowly return back to normal over time. Further experiments showed that hydrogen peroxide was able to remove the marks instantly, and an argon atmosphere slowed the rate at which the marks faded.
It’s an interesting look at an odd chemical effect, with the benefit of a well-equipped optics lab to analyse what’s going on. Following the phenomenon down the rabbit hole leads to some tips on how to extract fluorescent additives from common laundry detergent. Be it paper, plastic, or textile, if it looks really bright white to your eye it probably contains stilbene organic compounds as optical brighteners, a hidden trait you never actually thought about before. Video after the break.