I'm working on a project where I need to use an infrared (IR) camera that's filtered to only see wavelengths around 850nm. I'm interfacing with the camera using a Linux machine running Python OpenCV code, so it needs to be a camera that connects over USB.
From what I've researched so far, an IR camera can basically be made from a regular digital camera by using a special lens filter which only allows certain wavelengths of IR light to pass through it. (https://expertphotography.com/infrared-photography-basic-camera-gear/) There are also IR-specific cameras, but they tend to be very expensive (https://www.edmundoptics.com/p/EO-1312-NIR-USB-30-Camera/37395).
I'd like to create my own IR camera by getting a mid-quality USB camera and adding/changing a lens filter to an 850nm IR filter. Does anyone know of any mid-quality USB cameras ($30 - $150 range) that have interchangeable lenses/filters or would work well for an IR application?