4.19 Camera settings

Hello,

4.19 been out for a while now, still can’t figure out proper settings for new Camera Settings under PPV.

Documentation doesn’t explain anything useful for artists. Default values result in completely dark image.
As a person who never had anything to do with professional photography it’s a little confusing to find out what to do with those values.
I can only crank them up or down to make the image visible, but still have no idea what values are “correct”.

Some explanation on that would be very appreciated.
Thanks.