Nightvision on the cheap: Help me out.

Kurt_ · Post by **Kurt_** » Sat Jan 10, 2009 12:24 am

So I'm looking to make some sort of nightvision using a digital camera as a starting point.

I have two donated to me, and I'm currently screwing with the cheap 2 megapixel, no zoom model.

So far I've removed the infrared filter on top of the CMOS chip. However, what is displayed on the LCD is still very dark compared to what I can see with my naked eye. My question to you: Would amplifying the red line (where I assume the infrared is being absorbed, based on one graph I saw for a possibly similar CMOS sensor) create a clearer picture? Where would be the best place to put said amplifier? By the CMOS chip? By the LCD input?

I know none of you have done this, stabs in the dark are acceptable responses, they're good for ideas.

I was thinking an amplifyer using a simple transistor setup would work, but I'm also thinking It'd be nice to have the ability to adjust the amplification based on light levels (ie. a Pot/transistor setup?)

Help with that circuit?

Ben Cebhrem · Post by **Ben Cebhrem** » Sat Jan 10, 2009 12:42 am

I would assume right after where image processing would be ideal for clarifying and strengthening the red line; omitting the other line (or somehow blanking them out, idk). Of course, you'd need a way to strengthen and clarify it without boosting the voltage beyond anything that can safely display it (i.e., don't pump so much voltage in the line that you blow a screen).

Then again, it's the red sensors on the sensor-picture-taking-thingie that matter the most- a strong signal from them, and likely only them, would yield the most useful image, wouldn't you agree? In the end, that may not matter, but it could be a point of contention.

Kyo · Post by **Kyo** » Sat Jan 10, 2009 1:46 am

That amplifying circuit would be fairly simple.

I'd bother making a diagram, but I found one on google images for "adjustable amplifying circuit":

You can also use a 2n4401 in place of the 2n3904. As you can see this is similar to the circuit that ben uses in his atari and nes mods.

TAFKA_Cennar · Post by **TAFKA_Cennar** » Sat Jan 10, 2009 1:52 am

kurt what you need night vision for.

also the light level things a cool thing to play with.

Kurt_ · Post by **Kurt_** » Sat Jan 10, 2009 3:40 pm

Zombie apocalypse, night walks in a forest, a technical challenge?

I fail to see how that diagram is adjustable. Would more lenses capture more light? Obviously, but I mean, would it help more than the cost of buying the expensive lenses required.

Kyo · Post by **Kyo** » Sat Jan 10, 2009 3:42 pm

R2 is a pot

Kurt_ · Post by **Kurt_** » Sat Jan 10, 2009 3:50 pm

I KNOW that. Duh. Obviously.

What I mean to say is, adjustable as in like, yeah!

Kyo · Post by **Kyo** » Sat Jan 10, 2009 4:25 pm

not following you

Kurt_ · Post by **Kurt_** » Sat Jan 10, 2009 7:12 pm

That's the point.

Super Cameraman · Post by **Super Cameraman** » Sat Jan 10, 2009 9:29 pm

Wait, all you're doing is removing the IR filter?

That won't do anything to make the image brighter, you have to use IR lights now and wire them to a battery.

(sorry if that's what you are doing, but I couldn't find it in the thread)

Kurt_ · Post by **Kurt_** » Sat Jan 10, 2009 11:05 pm

I'm kind of going with the flow. That's all I've done SO FAR.

Doing that really sucks. Using an IR LED from a TV remote still sucks. I need to amplify the electrons converted by the CMOS sensor, and quite possibly slap an expensive lens on the front of the camera so more photons are converted in the first place.

hy phrend · Post by **hy phrend** » Sun Jan 11, 2009 12:09 am

There was a guy on instructables that made a homemade Night vision where he used some IR LEDs but they had essentially three LED's in each. He used 8 of these I believe, bought a IR camera and hooked it up to a view finder from an old video camera.

Since you took the IR filter off of your camera then that should work. and then just have a large IR LED bank that can put out a lot of IR light to light up things around you. Of course this would probably only work for things close to you but then again you could get a LED flashlight and replace them all with IR to shine longer distances.

I searched for the instructable but couldn't find it anymore... Google search brought up some stuff though but not the one I had seen.

Hope this helps.

timmeh87 · Post by **timmeh87** » Sun Jan 11, 2009 1:49 am

You arent going to do that much by amplifying the video signal coming from a camera in the dark.

Its kind of like turning up static on the radio.

You need to get an infrared lamp of some sort. Also image processing would help. If you take a picture with the lens covered, it will probably look pretty grainy. Subtracting that from the image will clean it up. The way the background noise in the sensor looks changes slowly over time and improves at lower temperatures...

Kurt_ · Post by **Kurt_** » Sun Jan 11, 2009 1:58 pm

http://www.howstuffworks.com/nightvision.htm

A lamp, like THE MOON?

Military night vision works on moonlight. I'm aware I'd need a light source in a house or something, but right now I'm trying to get something that will work with the light emitted by the moon.

Kurt_ · Post by **Kurt_** » Mon Jan 12, 2009 4:32 pm

Bump.

So. any flaws in amplifying the signal given a source as powerful as the moon?