Found this on another board. They guy just started testing it to day. So far, it works well.


The lens he got was this one.

http://www.irprostore.com/produc ... c-21c1-6b1610bdfcac

I'm going to order one this week.

How are you going to fit that lens to the P4 ? You'd have to gut the camera, would the imaging chip need changing for mono ? Otherwise Bayer filter would likely block IR to a degree.  I can only think of one similar example, most DSLRs have an IR block filter, because all the imaging chips are sensitive to IR. And those into astronomy imaging might remove that filter.
And then how would the gimbal cope ?

Sounds like a bit of a mine field.

Just watched the whole video, it's a great experiment, and if IR is what you want then fine.

You'd be ripping up your warranty though, and trying to restore previous might be difficult, trying to keep lens orthogonal to chip, and getting focus right.

This is all wrong, most cameras have an IR filter attached directly to the sensor itself to block IR light, as it can damage the sensor. There is no mention of removing that filter in the video clip, but more importantly, I could not see IR hot devices in the footage shown, so I am calling BS on this one. It just looked like a monochrome clip to me.

Looks perfectly good for near IR, which is what is used for vegetation analysis, and what this lens is designed for. It is not designed for far IR, AKA thermal IR (like flir captures). Near IR is reflected IR, thermal IR is emitted. That is why the sunrise footage shows no "heat", because this product, and the sensor in the camera, is not able to capture the thermal IR EMI Spectrum.

You guys know about as much as I know about it, well, probably a LOT more. I have a Flir R series scope/camera. The images are not the same, but it is over $4000 for the one I have. A hot spot can be set to appear in numerous ways on the R. I am staying in touch with him to see how it goes.  It is hard to believe IR for $140. Geebax may be on to some thing. Curiosity killed the cat, hopefully not the drone. I have two P4's, so I have an extra one to play with. It is fun to experiment with in certain parameters. This is just a discussion, I am not recommending any one do this. One of the things I found interesting that you could change the lens. But, the sensor. That could stop the feasibility of changing the lens. That didn't occur to me. fansda6d458a mentioned vegetation analysis. I saw where there was the $150 option to add that to the lens.

If your looking for something like a Flir - then no, this lens won't work. It is designed to work in the near infrared wavelengths (0.75–1.4 µm), just beyond the visible spectrum. This is also the IR that the P4 camera sensor can "see". Near IR sensors (and photographic film) are designed to typically capture light waves reflected from the sun. Thermal iR sensors, like you get with a Flir unit, are designed to capture emitted radiation (heat) in the Far IR range (15–1000 µm). The sensors in the P4 (or any off the self RGB visible spectrum camera) can not capture images from light waves (or the electro-magnetic spectrum) in this range. It takes sensors designed to capture thermal IR, hence why Flir, or similar units are so expensive.
Hope this helps!

If you were after IR/FLIR imaging in the first place, wouldn't it be better to get a craft with a gopro mount and use one of the many go pro compatible solutions available? I can't see the point in tearing down a perfectly good camera to do this.

fansda6d458a Posted at 2016-12-6 03:23
Looks perfectly good for near IR, which is what is used for vegetation analysis, and what this lens is designed for. It is not designed for far IR, AKA thermal IR (like flir captures). Near IR is reflected IR, thermal IR is emitted. That is why the sunrise footage shows no "heat", because this product, and the sensor in the camera, is not able to capture the thermal IR EMI Spectrum.

+1, a great explanation.

Aardvark Posted at 2016-12-6 01:44
How are you going to fit that lens to the P4 ? You'd have to gut the camera, would the imaging chip need changing for mono ? Otherwise Bayer filter would likely block IR to a degree.  I can only think of one similar example, most DSLRs have an IR block filter, because all the imaging chips are sensitive to IR. And those into astronomy imaging might remove that filter.
And then how would the gimbal cope ?

In most of the recent Sony sensors, the red pixels are sensitive to both red and near infra red, but not far IR (thermal), the green pixels also pick up a fair amount of near IR.

Normally there is a IR cut filter on the back of the lens to block the IR from reaching the sensor, all you need to do to collect IR is to remove the IR cut filter, better than changing the lens as it is so light it will have no effect on the gimbal.  If you want IR only then you need to also add a visible cut filter so that the red pixels only see IR, but if you are only doing it to get interesting photos then you can leave it receiving both IR and visible colours.

These where taken with my Gitup Git2 Action Camera with the IR cut filter removed (very easy to do):

Near IR only, visible removed by visible cut filter, photo taken in sunlight:



Near IR + visible:

Couple more ??? GoPro has a IR set up? Why is near IR used for vegetation? I can't grasp the concept of near and far IR. IR is heat. If it is reflected it is still heat, or is it ?

AnchorageAk Posted at 2016-12-6 20:01
Couple more ??? GoPro has a IR set up? Why is near IR used for vegetation? I can't grasp the concept of near and far IR. IR is heat. If it is reflected it is still heat, or is it ?

Near IR is just another colour, just beyond red in the rainbow, one that our eyes are not sensitive to but many other animals are.   Most green vegetation happens to be very bright in this colour so it can make for interesting photographs if you convert them to monochrome so that we can see them, or swap the IR with red, green or blue so that we can see them.   Near IR is also used by IR remote controls and IR security lights so that an area can be lit without you being able to see any light.

Far IR is another colour, a lot further away from red, and one that all objects give off, the exact frequency depending on their temperature.   If you get things hot enough then the frequency they radiate gets up into the red and we can see things that are red hot.