Why do my ENVY 14's webcam become so dark?

After I used recovery function my laptop for about 3 times, the webcam become so dark in the afternoon and night! But in the morning, it work normally (in fact, it's a little brighter before the recoveration) , these pictures were taken at 15:45, the dark one is from the envy's webcam, the bright one is from an usb 2.0 camera. The last one was taken by envy's webcam at 9:00 (in the morning). Do you know why is it?

 

I had the same problem with my HP Pavilion dv6t. The way I worked around it is to play around with the settings.

To do this:
1. Click on the button with the film and a bulb-looking thing. This is the settings button. A new window should appear next to the main window.
2. Click on Advanced. This should pop-out another window. This is where you can play around with the settings.
3. What worked best for me is increasing 'gamma' to max (500).
4. Click on the 'Camera Control' tab. Set 'Exposure' to auto.

5. (Optional) You can also play around with the 'Low Light Compensation'.

 

THank you so much men, i'm very need it for my conversation with my family