[HOWTO-WIP] Infrared photography
 

So I decided a few weeks ago to try my hand at removing the IR filter on the N900, because IR photography is awesome.

I ordered a module on ebay, so I wouldn't break my current one.
I broke the one I bought, and broke my original one when I was removing it from the phone.

45 minutes later, disassembling and reassembling the phone twice (because after doing it once, the N900 doesn't turn on until you disassemble and reassemble again), I have a working infrared camera on my N900- other than the broken autofocus and damaged sensor from scratching it when removing the IR filter.

http://i.imgur.com/sOxpo.png

The light (in the "Light off" image) is from a 1.2v 20mA IR LED. I'll take some day pictures tomorrow, when it's day. Once my new module comes in, if I don't break it again I'll have nicer focused pictures.

Re: [HOWTO-WIP] Infrared photography
 

great thingy dude .

Re: [HOWTO-WIP] Infrared photography
 

http://i.imgur.com/2rIUw.jpg

Found a piece of broken filter from where I took it out to compare before/after, top is holding piece of the filter infront of the LED and the bottom is without it.

Re: [HOWTO-WIP] Infrared photography
 

It would seem not many people find IR too interesting.

Re: [HOWTO-WIP] Infrared photography
 

Is there a reason you are using 940nm LED's?
You should get a better night picture with a lower frequency.
The only benefit of using higher frequency IR is to make it more invisible to humans.

Re: [HOWTO-WIP] Infrared photography
 

How much was the spare camera?

Re: [HOWTO-WIP] Infrared photography
 

isn't it the other way round? Seems more intuitive to assume a frequency higher on a band below visibility is more visible than a frequency far off the visible range.

/j

Re: [HOWTO-WIP] Infrared photography
 

IR photography is awesome.Used to have an old camera and hacked it for this purpose :)

Re: [HOWTO-WIP] Infrared photography
 

No, although I do apologise were I said frequency I actually mean wavelength.
I deal with infra-red and cameras as part of my job.

Humans can see light between ~380nm and ~740nm.
IR covers from there to about 1mm.

IR LED's come in different wavelengths
I install these at work, the 850 is slightly visible (has a glow) whereas the 940 is invisible to the naked eye.

Using 850nm compared to white light reduces camera efficiency by ~25%, whilst at 950nM it can be reduced by over
60%.

Also less applicable here is the problem of focus shift, which is were a fixed lens camera becomes blurry while using IR.
The lower wavelength IR's reduce this effect.

Re: [HOWTO-WIP] Infrared photography
 

So actually "yes", since higher wavelength means lower frequency ;-)

/j