Holograms are tricky to describe because science-fiction gives the name to any three-dimensional image. The science-fact versions are not as flashy, but they are still darn cool. Legitimate holograms are images stored on a photographic medium, and they retain a picture of the subject from certain angles. In other words, when [Justin Atkin] makes a hologram of a model building, (video, embedded below) you can see the east side of the belfry, but when you reorient, you see the west side, or the roof if you point down. Holography is different from stereoscopy, which shows you a 3D image using two cameras. With a stereoscopic image, you cannot tilt it and see a new part of the subject, so there is a niche for each method.
There are a couple of different methods for making a hologram at home. First, you probably want a DIY hologram kit since it will come with the exposure plate and a known-good light source. Far be it for us to tell you you can’t buy plates and a laser pointer to take the path less traveled. Next, you need something that will not move, so we’re afraid you cannot immortalize your rambunctious kitty. The last necessity is a stable platform since you will perform a long-exposure shot, and even breathing on the setup can ruin the image. Different colors come from the coherent light source, so getting the “Rainbow Holograms” advertised in the video is a matter of mixing lights. Since you can buy red, green, and blue laser pointers for a pittance, you can do color remixes to your content.
Another type of hologram appears on things like trading cards as those wildly off-color (chromatic, not distasteful) images of super-heroes or abstract shapes. They’re a different variety, which can be printed en-masse, unlike the one-off [Justin] shows us how to make.
If you’re yearning for volumetric displays, we are happy to point you to this beauty capable of showing a jaw-dropping 3D model or this full-color blocky duck.
Continue reading “Hello, Holograms”
Companies spend thousands developing a project for the market, hoping their investment will return big. Investing like this happens every day and won’t shock anyone. What may surprise you is someone who spends more than a decade and thousands of their own dollars to make an open-source version of a highly-marketable product. In this case, we’re talking about genetically modified yeast that produces spider silk. If that sounds like a lead-in to some Spiderman jokes and sci-fi references, you are correct on both accounts. [Justin Atkin] had some geneticist work under his belt when he started, so he planned to follow familiar procedures like extracting black widow DNA, isolating and copying the silk genes, and pasting them into a yeast strain. Easy peasy, right? Naturally, good science doesn’t happen overnight.
There are a few contenders for the strongest spider silk among which the golden silk orb-weaver gets the most attention, but the black widow’s webbing is nearly as strong, and [Justin] is happy to wear black widow inspired bling, whereas the golden orb-weaver looks like it crawled out of Starship Troopers. His first attempt to extract DNA starts with a vial of preserved
nightmare fuel spider specimens because that is a thing you can just go online and buy. Sadly, they were candied in alcohol, and that obliterates DNA, so he moved to dried specimens from breeders, which also failed to produce results, and those were just the landmark hangups.
Continue reading “Spider Silk, Spider Silk, Made Using A Strain Of Yeast”
We hope you have been good this year because we have a list to start your own biology lab and not everything will fit into Santa’s bag (of holding). If you need some last minute goodie points, Santa loves open-source and people who share on our tip line. Our friends at [The Thought Emporium] have compiled a list of the necessary equipment for a biology lab. Chemistry labs-in-a-box have been the inspiration for many young chemists, but there are remarkable differences between a chemistry lab and a biology lab which are explained in the Youtube video linked above and embedded after the break.
If you are preparing to start a laboratory or wondering what to add to your fledging lab, this video is perfect. It comes from the perspective of a hacker not afraid to make tools like his heat block and incubator which should absolutely be built rather than purchased but certain things, like a centrifuge, should be purchased when the lab is mature. In the middle we have the autoclave where a used pressure cooker may do the trick or you may need a full-blown commercial model with lots of space and a high-pressure range.
Maybe this will take some of the mystique out of starting your own lab and help you understand what is happening with a gel dock or why a spectrophotometer is the bee’s knees. There are a handful of other tools not mentioned here so if this is resonating, it will be worth a watch.
Continue reading “Biology Lab On Your Christmas List”