[jazzyjackson]

With the use of a sensor or film sensitive to infrared light, and optionally the use of deep red/orange lens filter to block out all the other wavelengths.

Rollei still manufacturers infrared 35mm film, I think it used to be used for aerial surveying, because green foliage is also reflecting lots of infrared

For digital cameras a lot of sensors are already sensitive but it's undesirable because it shows up as false colors, red hot things will appear pink or purple, so digital cameras have internal infrared filters. Go on eBay and search infrared converted camera, lots to choose from, iirc it's a pretty simple surgery if you're the type to take things apart and put them back together

Here's a nice guide for more https://phlogger.co.uk/how-to-shoot-colour-infrared-film-by-...