31–40 of 69 posts
> But for our goal it’s important to remember, because infrared light does not pass through glass 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.
Earlier quoted context omitted.
Snakes are seeing in the closest to visible specter IR IIRC. Also they have evolved a lot of other sensory mechanisms to detect pray - sounds, vibrations, taste
https://en.wikipedia.org/wiki/Infrared_sensing_in_snakes They can sense radiation between 5 micrometers and 30 micrometers.
I wonder if the ribbonfarm guy could use a variant of this for his pixel scanner thing?
This is a great story, but the original title of "Artem vs. Predator" is much better than the submitted one.
The title is artem v predator, but gives zero information of the content. I clicked out of curiosity but usually avoid vague titled links.
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!
When I read this I thought, "nah"... but some digging later and
Nice way to start the day ;) Can't someone send this guy a box of gently used CCDs and some wideband lenses already or maybe an old copy of labview... 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!
A cool property of NIR filters is that they are able to produce a relatively recognisable picture of the world with all screens (TFT, projected) filtered out. I've used this in the past for computer vision to do object recognition on top of a projected display without having to programmatically filter out the projection. It's also pretty easy to make a rudimentary NIR filter by layering a red, green and blue filter o…
I assume the distortions at the edge of the 'photos' is due to the X Y scanning rig. Moving the sensor around the edge of a sphere (on a curved X Y (and a little bit of Z) rig, the focal point being the center of the sphere) would sort that right out. 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 s…
No it's a property of pinhole diffraction: https://en.wikipedia.org/wiki/Airy_disk
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.
It is possible to see in near infrared - just use a IR filter (used for photography), and stick it to your eye. Everything should look dim and reddish, but what is characteristic (and different from a red filter) is that leaves are very bright. Also, many black t-shirts are not-dark. Also, it's fun to make such photos: http://migdal.zenfolio.com/ir-old
Infrared film used to be available commercially with sensitivity up to 900nm. It was quite useful for aerial photography work – forestry, surveying, spying. Very little of it is still around. Kodak Ektachrome was what one could get for your high school dark room. Aerochrome for surveying work. It was discontinued in 2009. Ilford however still makes some. Be forwarned, finding someone to develop the stuff is a nightma…
Do you have do develop those films in the freezer? A normal dark room is not really dark at those wavelengths, even if you turn the red lamps off, right?
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.