It's also pretty easy to make a rudimentary NIR filter by layering a red, green and blue filter on top of each other: the resulting filter will not allow any visible light through (e.g. red, green or blue), only the "rest".
edit: and they make your eyes look really creepy too (not me in the picture btw): https://flic.kr/p/6CYzDZ
I expect the 3D printer could make a curved rail for the rig.
Or you could point the sensor at the center of the pin hole or lens using a mechanical linkage, then use some software to warp the resulting image.
The lenses give the radial blur at the edges effect, pinhole gives the darkening at the edges effect.
Airy disk affects brightness and sharpness, not warping.
You could put a camera lens where the pin hole is to negate this warping, but that defeats the point of a pin hold camera.
How is this system better than a commercial IR camera -- besides the very obvious and valid reason that this is DIY, and started long before those were cheap?
> "The most amazing part is not that it glows, but that it glows brightly enough to illuminate the stand. It’s not just the “temperature mapped to an image” of a regular heat vision camera, we see the actual long-wave light being emitted and reflected – a soldering iron turned into a lightbulb!"
How is that different from this image, which shows a duck's IR being reflected by water, made by a cheap-o "regular heat vision camera"? http://thermal-imaging-blog.com/wp-content/uploads/2012/05/d...
Higher-quality IR imaging equipment is photodetector based (as in, they operate on the photoelectric effect); these require very low temperatures to operate and need the sort of active cooling the author refers to.
See also https://en.wikipedia.org/wiki/Thermographic_camera , which goes into detail on the different technologies involved.
Just kidding, this has to be one of the coolest projects I've ever seen. To make all this by yourself is just ... awesome.
This was my first encounter with ITAR – the “how dare you
want interesting stuff?” restrictions. Before then I
never realized just how USA, uh…, loves the whole world.
When I read this I thought, "nah"... but some digging later and
They can sense radiation between 5 micrometers and 30 micrometers.
Oh and Artem, if you happen to see this, can you try getting out of the city on a cloudless night and taking a long exposure of the night sky? Thanks for your hard work and inspiring us all!
https://upload.wikimedia.org/wikipedia/commons/f/f8/Star_tra...
WiFi is closer. High microwave is probably what you want here.
And of course, this already exists. It's called radar. Haven't seen any radar "photos" though. Interesting if that's indeed possible.
FM Radio (100MHz) has 3m wavelength. You'll need a giant camera and will be able to see only very big structures.
Wifi/Microwave/Radar is in the Gigahertz range. 2.5GHz == 12cm wavelength. For radar photos, you'll need a very big camera, and a human would be only a few pixels big.
Some airport scanners are based on millimeter waves (teraherz radiation), and you can find sample photos online. They produce pretty blurry pictures, but clothes become partially transparent.
Oh, right, synthetic aperture radar. Duh. Should have thought of that. :)
I thought that was UV?! If that statement is true, how on earth am I able to busk in the heat of the sun behind a glass window, indoors?
It is what bodies at low temp (like a human being) radiates the most. Higher energie bodies also radiates higher energy light, such as visible light and UV.
Scientific infrared films, such as special formulations of AeroChrome I, II, II, approached sensitivity up to 1200nm.
In surveillance work, objects which were painted to look like their natural environment using various organic or inorganic paints may show up quite differently in the infrared spectrum.
In forestry work, old growth tree populations could easily be distinguished from new growth tree populations and were one of the primary uses for Nasa's version of the U2 (ER-2) for identifying old-growth redwood populations in northern California. [1]
A lot of work was done in the 1970's and '80's by astronomers and physicists to 'hack' Eastman Kodak scientific film, or plates as they were called. (Once you move past "point and shoot" film, you get into the realm of plates, 4"x5" trays similar to old-timey 1880's cameras.) Things like Kodak I-Z. One technique was to hypersensitize the film by bathing it in Ammonium Hydroxide [2]. Lawrence Livermore had such an appetite for IR-sensitive film with their laser work that they set up their own production process for hypsersentizing Kodak scientific plates. Another was to supersensitize them with acetic solutions getting film sensitivity in the >1500nm range [3]. This seems to be the limit of our knowledge for traditional chemical film processes.
Modern DSLR's have sensitivity up to 1600nm. Nikon worked with NASA for some of their special DSLR's [4].
One of the cooler things I saw was a University of Florida paper in Nature that used IR-OLED's to upconvert IR to visible light through a lens adapter achieving sensitivity from 400nm to 2000nm [5].
Beyond 2000nm you get into the MWIR range and FLIR devices take over.
[1] https://books.google.com/books?id=HZUTCgAAQBAJ&pg=PT129&lpg=...
[2] http://www.osti.gov/scitech/servlets/purl/4442636/
[3] https://books.google.com/books?id=nlftCAAAQBAJ&pg=PA259&lpg=...
And yes, it takes time to learn to navigate the room and work in pitch blackness. Gave me a lot of respect for the blind. At school, we could develop one roll at a time, allowing for the use of small containers which would let you work within a dark bag for a small period of time. At the photo shop, they had a machine for processing film in batches of 10+, which required the entire room to be dark while loading it.
Modern film processors frequently don't even require the dark box (unless the film canister is in really bad shape) - just stick it in, close the door, push a button. Remarkably slick.
Also, it's fun to make such photos:
http://amasci.com/amateur/irgoggl.html
He has some very interesting photos taken with them. He also cautions about the iris being opened wide when wearing them, although he claims that he's suffered no ill effects after using them for years (avoiding looking at the sun, of course).
No, it isn't. The "infrared light is heat" statement is casually-useful but technically-false, which means it backfires and harms people when they start learning more about physics.
IR radiation is not the intrinsic heat-content of the matter emitting it. Infrared is simply a particular set of wavelengths which happens to be prominent for temperatures which are "hot" for us just because we evolved on this small rocky planet which has a certain baseline temperature.
Go ask some icy crystalline aliens or ones powered by low-grade nuclear reactions what they think about "heat radiation" and you won't get the same answer.
I think that regarding the near infrared light a regular CCD element could be useful as well, as those are sensitive to infrared too. The only problem is to filter the visible light to leave the infrared spectrum only. Also be sure that the ccd doesn't have a IR filter (some does).
"This project spans years, and when I started there were no 3D printers. Eventually I made one"
"Okay. The purpose of the problems is to be solved."
