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Artem vs. Predator

ribbonfarm.com

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Re: Artem vs. Predator

#41

Post by Artlav »

monk_e_boy wrote: post #16

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…

About half of the pictures in the article are taken with the lens assembly. Pinhole is good for outdoors and sunshine, but is useless for MWIR/SWIR and indoors scenes, even with my 600W Metal Halide lights.

The lenses give the radial blur at the edges effect, pinhole gives the darkening at the edges effect.

Re: Artem vs. Predator

#42

Post by AnkhMorporkian »

sangnoir wrote: post #25
panic wrote: post #24

Earlier quoted context omitted.

Yes, I think this is a common misconception: infrared light is "heat radiation" in the sense that it's emitted from hot things, but any wavelength of light you absorb (not just IR) will heat you up.

> but any wavelength of light you absorb (not just IR) will heat you up Thanks - this is the bit I was un-/miseducated about. When we were taught about radiation in high school, I suspect my young mind concluded that since infrared and visible light were mutually exclusive on visibility, the same applied to heating. To this day, I thought infrared → heat and heat → infrared.

I just happens that at everyday temperatures familiar to humans, the primary wavelengths emitted are infrared. Heat something enough, and that curve will shift to predominantly visible wavelengths; think about an electric oven.

Re: Artem vs. Predator

#43

Post by Artlav »

gregorkas wrote: post #12

You know those black and white photos? I thought Russia looked like that with regular cameras :P. Just kidding, this has to be one of the coolest projects I've ever seen. To make all this by yourself is just ... awesome.

Here is one of the more apocalyptical ones (i call it "The storm is coming"): http://i.imgur.com/zFD4znl.jpg

Re: Artem vs. Predator

#44

Post by alex_c »

t_fatus wrote: post #3

Never Give Up.. This should have take SOOOOO long, with so many disaopointment ! Really nice job

This is probably my favorite line from the entire post:

"Okay. The purpose of the problems is to be solved."

Re: Artem vs. Predator

#45

Post by StavrosK »

Artlav wrote: post #36
fitzwatermellow wrote: post #34

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!

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...

Re: Artem vs. Predator

#46

Post by sdfjkl »

mmastrac wrote: post #2

This is a great story, but the original title of "Artem vs. Predator" is much better than the submitted one.

I amuse myself with the thought of this contraption being fitted inside the Predators face mask. I'm easily amused.

Re: Artem vs. Predator

#47

Post by [deleted] »

d--b wrote: post #18
monk_e_boy wrote: post #16

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

[deleted]

Re: Artem vs. Predator

#48

Post by cma »

monk_e_boy wrote: post #38
d--b wrote: post #18

Earlier quoted context omitted.

No it's a property of pinhole diffraction: https://en.wikipedia.org/wiki/Airy_disk

The buildings at the edge of the photos look warped. Like an extreme fisheye lens would do. 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.

Yes, it is proably more petzval field curvature than diffraction limiting: https://en.wikipedia.org/wiki/Petzval_field_curvature

Re: Artem vs. Predator

#49

Post by haddr »

Cool stuff!

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).

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