Using camera to detect IR radiation?

How to? I have a digital camera.... Thanks.

Most digital cameras have IR blocking filters, but some IR light still goes through. All you need is to point your IR source towards the camera.

Older models tend to work better. Use a remote control to test how sensitive your camera is to IR. I believe remotes use 980nm, so if your camera can see that, it's certainly going to see 808nm .

Very simple

What camera do you own?

All of the point and shoots I have owned have been IR sensitive. Some more than others. Sony's with the Night shot mode are most sensitive. My Nikons were second and Cannon was last. Some Nikons have the internal blocking filter so they see no IR.

If yours can see the IR from a remote then an expensive filter can block all but the IR light. Then you can do some IR photography. Of course you need your camera to be able to mount the filter and focus is going to be manual if possible or set your controls on Infinity (mountain or scenic setting). With such a small lens to start with depth of focus is pretty good most of the time.