How to turn off auto brightness adjustment on the WEBCAM

Hi there. I am lucky enough to have a desk in front of a window, so I have tons of natural light shining on to my face and room. With a properly adjusted camera, this looks wonderful. However, Windows has decided that their auto-brightness on the webcam is just perfect, and therefore there is no reason anyone would want to turn it off, so as far as I know, you can't turn it off in settings. It is not perfect. When I go into the camera app, into "Pro" mode, and adjust the brightness slider, the image looks perfect, the background not under-exposed, and my face not over-exposed. However, when I am in a zoom meeting or such, the camera is constantly fluctuating, zooming back and forth from me being a white blob to turning my brown hair black. I do not want this, this an artefact of the CAMERA auto-brightness, NOT the screen auto-brightness. Please, do not leave me a link on how to disable screen auto-brightness, that is all I am seeing on similar questions, and that is NOT what I am looking for.