This was a fascinating read. Thanks for sharing.
Artem vs. Predator
51–60 of 69 posts
Re: Artem vs. Predator
#52Earlier quoted context omitted.
Artem here, that's a strange idea. Right now the sensor got a fixed gain, and so exposure time is meaningless. It won't be too hard to add, but what sort of image would there be, with the frame time of many hours, line by line as the planet rotates? Sounds curious enough to try. :) I anticipate a distorted starfield - every star as a bright point, but all of them shifted in position.
Just star trails, probably: https://upload.wikimedia.org/wikipedia/commons/f/f8/Star_tra...
Yes, but distorted because of the way the sensor is also moving.
Re: Artem vs. Predator
#53Earlier quoted context omitted.
https://en.wikipedia.org/wiki/Infrared_sensing_in_snakes They can sense radiation between 5 micrometers and 30 micrometers.
Wow, so instead of a photochemical or photoelectric effect, it's actually literally a heat sensor - as in, radiation from the environment heats the interior of the heat pit (which is cooled by the snake's blood to maintain a baseline) and it is this change in temperature that is detected? I wonder if the ribbonfarm guy could use a variant of this for his pixel scanner thing?
That is the operating principle of a bolometer.
Re: Artem vs. Predator
#54So is the future wavelength project something like radio waves? It would be fascinating to see an image lit by radio waves. Imagine a wifi router being lit up like a lightbulb, casting shadows around a room, or a room lit by FM radio passing through walls and windows, etc.
Unfortunately the resolution of your image will decrease with an increasing wavelength so you might end up with a pretty fuzzy radio-picture.
Re: Artem vs. Predator
#55 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.
Re: Artem vs. Predator
#56This guy is spectacular. Check out his other work: http://orbides.org/ Here is a nice concept of an interstellar ship http://orbides.org/concepts.php?lng=eng
Re: Artem vs. Predator
#57Forgive my ignorance, but if this system would require liquid nitrogen cooling to detect heat from a human, how do commercial (now almost cheap) thermal cameras work? Are they not sensing IR? The can certainly distinguish the different temperatures of different people, without needing to be cooled themselves.
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...
Re: Artem vs. Predator
#58"..when I started there were no 3D printers. Eventually I made one, and all the clumsiness of the old rig got replaced with modern, 3D printed, well-fitted parts." When I read this I thought, "nah"... but some digging later and http://orbides.org/page.php?id=703&lng=eng
I've seen a lot of hacky DIY 3D printers, but this is the roughest. Love it!
Re: Artem vs. Predator
#59Have you tried zone plates instead of lenses? Feature sizes should be larger for IR than for visible light, so it's should be possible to fit enough zones to get some focusing.
Re: Artem vs. Predator
#60Have you tried zone plates instead of lenses? Feature sizes should be larger for IR than for visible light, so it's should be possible to fit enough zones to get some focusing.
To expand a bit on construction: it's possible to take a long tube, put a fresnel lens at front, pyroelectric sensor with rotating shutter at the other end. Scan by rotating it with reductors/steppers as a whole. It's also possible to cool tube with contents down to -70 with dry ice to cut on background heat radiation. Maybe it'll lessen noise in pyroelectric sensor, maybe not (and it's quite easy to buy dry ice in Moscow).