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Doesn't work like that. Overexposing (with the same light) means having worse SNR due to higher gain. The choice to use typically terrible cameras in a proctor
by frostburg 5y ago
Doesn't work like that. Overexposing (with the same light) means having worse SNR due to higher gain.
The choice to use typically terrible cameras in a proctoring system disregarding that it might work ever worse than normally for a subset of people is suspect, yes.
- tshaddox 5y agoBut wouldn't it be just as easy to create a cheap camera that tends to correctly expose dark skin in normal lighting conditions, and cannot dial down exposure enough to prevent light skin from being blown out in normal lighting conditions? If that's possible but cheap cameras tend to not work this way, then why is that not the case?
- frostburg 5y agoYes and no, but mostly no. Lighter skin reflects more light (which means more signal), so it's inherently easier to image (it would be harder in extremely intense light, but getting fast shutter speeds is a lot easier than dealing with not having enough photons). Auto-exposure algorithms tend to work more accurately on lighter skin, too, which could be improved but is generally not something implemented at the hardware level in a webcam as far as I know (software can ask for different iso sensibility and shutter speeds).