Humor Random Comments Thread

[jedidia]

Just spent over 30 minutes watching various slinky videos... XKCD what if is becoming just as evil as TVTropes...

 

[Artlav]

Good news: There are SWIR photodiodes on sale now, and they are much less sissy than InAs MWIR ones.
http://www.digikey.com/product-detail/en/MTPD1346-010/1125-1027-ND/2798893

Bad news: In 1300nm SWIR light the things look about the same as in 800nm NIR one. The clouds seem denser, but only a little.

Outdoors:

Indoors:

Sunset:

There should be a water absorption region around 1300nm-1400nm.
I'd love to get a notch filter for that and see what the world is like in there.
No clue where to get it, however...

 

[kamaz]

A photodiode is a 1 pixel detector... how do you scan the image?

Re: filters...
http://www.alluxa.com/optical-filters/custom-oem-filters
http://www.evaporatedcoatings.com/custom-optical-filters
http://www.omegafilters.com/capabilities/infrared-filters/
http://www.newport.com/Custom-Bandpass-Filter-Capability/372584/1033/content.aspx

 

[Artlav]

A photodiode is a 1 pixel detector... how do you scan the image?

With a cartesian scanner in a box:
http://hackaday.com/2015/01/21/diy-single-pixel-digital-camera/
http://orbides.1gb.ru/photobot.php?lng=eng

Re: filters...

Thanks, might come in handy.
There are some local manufacturers as well, but it's often an issue of price or minimum order size.

 

[BruceJohnJennerLawso]

With a cartesian scanner in a box:
http://hackaday.com/2015/01/21/diy-single-pixel-digital-camera/
http://orbides.1gb.ru/photobot.php?lng=eng

Thanks, might come in handy.
There are some local manufacturers as well, but it's often an issue of price or minimum order size.

So you just take the one photodiode and have it "crawl" along the image projected into the pinhole camera to scan the whole image?

 

[Artlav]

So you just take the one photodiode and have it "crawl" along the image projected into the pinhole camera to scan the whole image?

Essentially, yes.

Add a box of filters, and you can get colour images as well.
Visible:

NIR+G+B:

NIR+R+G:

But what i really wanted to, what i have started the whole project for, is to see in light no cameras on free sale can see.

3400nm:

2000-3500nm:

1000-1500nm:

I also tried to image sound, and some other weird experiments like that, with no success.

 

[Andy44]

I also tried to image sound, and some other weird experiments like that, with no success.

There is a smartphone app called "Phonopaper" which actually "images" sound, and if you print the image out, and scan it with your phone it will read it back to you out loud. It's a neat toy, although probably not exactly what you're talking about:

https://play.google.com/store/apps/details?id=nightradio.phonopaper

[ame="http://www.youtube.com/watch?v=-GAJ9e8ifYU"]PhonoPaper: Play Music from Paper - YouTube[/ame]

 

[Linguofreak]

There is a smartphone app called "Phonopaper" which actually "images" sound, and if you print the image out, and scan it with your phone it will read it back to you out loud. It's a neat toy, although probably not exactly what you're talking about:

That's an app to do a sound spectrogram, which is indeed quite fun. I think what Artlav is talking about is more along the lines of passive sonar. Thing is, the sound environment in the average human habitation is probably too variable for a pixel-at-a-time passive sonar, and there are probably issues with diffraction, insulation, and the fact that the box and the ground it's sitting on are more transparent to sound than the air it's trying to image through.

 

[Artlav]

There is a smartphone app called "Phonopaper" which actually "images" sound, and if you print the image out, and scan it with your phone it will read it back to you out loud. It's a neat toy, although probably not exactly what you're talking about:

Neat, but an entirely different thing.

What i meant is to have a microphone on the scanner rig, a "pinhole" in the box, and an ultrasonic "light" to see.
Imaging in sound waves, literally.

Long story short, i wasn't able to get out of the noise floor.
It's like imaging with a camera made out of glass and mirrors, and with parts making light inside of it.

Pretty much the only meaningful result i could get is a wooden beam between the speaker and the camera (at 16Khz, AFAIR):

 

[MattBaker]

"And the term 'rickroll' you said it tries to make people go to a site where they think it's going to be one thing, but it is a video of Rick Astley, is that right?"

"Yes."

"He was some kind of singer."

"Yes."

"It's a joke?"

"Yes."

:lol:

 

[Andy44]

Neat, but an entirely different thing.

What i meant is to have a microphone on the scanner rig, a "pinhole" in the box, and an ultrasonic "light" to see.
Imaging in sound waves, literally.

Long story short, i wasn't able to get out of the noise floor.
It's like imaging with a camera made out of glass and mirrors, and with parts making light inside of it.

Pretty much the only meaningful result i could get is a wooden beam between the speaker and the camera (at 16Khz, AFAIR):

Ah, I see, basically making an image out of reflected sound waves. Very cool idea. Isn't that how fish finders work on fishing boats?

 

[jedidia]

Ah, I see, basically making an image out of reflected sound waves. Very cool idea. Isn't that how fish finders work on fishing boats?

I thought that was basicaly echo-location? (i.e. sonar...)

 

[Andy44]

I thought that was basicaly echo-location? (i.e. sonar...)

Yes, and if you take echoes from regular points on an X-Y grid placed over the scene in front of your sensor, you can form an image.

What I think Artlav is talking about is doing much the same, except instead of sending indicidual sound pulses, you "shine" ultrasound waves over the scene and read the return.

 

[Urwumpe]

Yes, and if you take echoes from regular points on an X-Y grid placed over the scene in front of your sensor, you can form an image.

What I think Artlav is talking about is doing much the same, except instead of sending indicidual sound pulses, you "shine" ultrasound waves over the scene and read the return.

Yes, but it would work better maybe, if he selects color on the phase shift.

 

[Artlav]

Hm, i might revisit it, now that the rig is more mature and i know more tricks.
Perhaps i should try to modulate the illuminating sound, or use some other feature than would make it unique enough.

I thought that was basicaly echo-location? (i.e. sonar...)

Yeah, only spatially resolved.
Direct analogy with light - you shine light, a lens focuses it, an (virtual) array of sensors produce an image.

You shine the sound, a hole focuses it, an (virtual) array of microphones form an image.

Essentially, Bat-vision.
Comic-book style.

 

[Athena]

http://rt.com/news/226279-robotic-car-autobahn-germany/

Woah, is this true? :blink:

 

[Urwumpe]

http://rt.com/news/226279-robotic-car-autobahn-germany/

Woah, is this true? :blink:

Yes, its true - A section of the A9 is considered to be opened for experimental robotic cars, within the project "Digitales Testfeld Autobahn".

http://www.bmvi.de/DE/Digitales/Dig...utobahn/digitales-testfeld-autobahn_node.html

http://www.heise.de/newsticker/meld...e-fuer-autonome-Autos-einrichten-2528191.html

The main research item though is currently just car2car communication, the section is getting equipped with communication and navigation gear for the research project this year. The robotic car initiative is not yet decided, but especially Audi and BMW want it, both companies are close to the test section.

The section close to Munich is one of the most crowded autobahn sections in Germany, with up to 184,000 cars per day on eight lanes.

 

[MattBaker]

I think I'll add "Drive to Zurich to see guys playing chess" into the list of "poshest things I ever did" this february. I feel like I'm turning into one of those people, please send help.

 

[Spacethingy]

Yes, its true - A section of the A9 is considered to be opened for experimental robotic cars, within the project "Digitales Testfeld Autobahn".

I think I'll add "Drive to Zurich to see guys playing chess" into the list of "poshest things I ever did" this february. I feel like I'm turning into one of those people, please send help.

How about driving to Zurich while playing chess?

 

[Athena]

"Drive to Zurich to see guys playing chess" into the list of "poshest things I ever did"

Hey, at least its not that bad yet...