Question Webcam image quality and fps

Hi, guys,
I want to create a marker detection function in hololens 2. Now I am using Logitech C920 to test the function. But I find when I use Webcam, the image quality is not good as it supposed to be, so I searched online and changed the webcam profile. I change the required texuture width and height. However, when I test in unity play mode, I found the fps is pretty low, I can notice the lag when I set 1280x720 resolution. When I change to 1920X1080, it is extremely slow. But the datasheet of C920 shows that it supports 1920x1080/30fps. So I was wondering how can I make it. In addition, when I want to set for hololens 2 camera, which profile I should change. I mean in webcamprofile, there are a lot of camera name, I am not sure which one is for hololens 2 camera.
Thank you very very much for your help!