It sometimes happens with cheap webcams, that as images taken inside (in the room) are well exposed, the images taken outside (eg from window) are far too bright. They are overexposed. This is because those webcams have fixed aperture, which is set for low light environment (like room). When we want to take photo outside, especially during sunny day, too much light gets into the sensor and image is too bright:
The solution could be disassemble the camera and install new aperture, with smaller hole (like here). But there is simpler (and probably better) solution.
Our cheap webcam needs sunglasses. Yes:
After this operation, the images are better exposed:
Of course, the best solution would be obtaining camera with adjustable aperture :)