Catch?
 

NFHS, Varsity night game. Outfield fence is around 6 feet tall completely covered with black cloth or netting.

Deep fly ball is hit to right field. Right fielder turns and runs to the fence. The ball comes down inside, right next to the fence, as the fielder arrives, chest high.
The fielder, still with her back to the infield, standing by the fence, holds the ball up with her open hand.

Catch or no catch?
How would you rule on such a play?

Do you have any evidence, sight, sound etc that it hit the fence or any other object or ground? You simply have to rule on what you saw and/or heard. If nothing tells you it hit anything but the fielder then you have a catch.

Or, if you did not see a clean catch, it wasn't. An out has to be for sure.