In 2015 I started reading about "The Harris Shutter" (look it up, it's interesting) and started thinking "what else could I do with this technique?" I started doing my own version using a full spectrum modified camera, a square hot mirror filter and a square infrared filter (somewhere around 800nm it seems). I would set up a tripod , take a photo with auto white balance and the hot mirror filter to get a normal color image then quickly change to a custom white balance for IR and replace the filter for the IR one. In Photoshop I would layer the images and blend accordingly.