My club has a prochrono, ours will only work outside on sunny days. It has been back more than once with software problems !Frankly I am not impressed with it.
Surely some one can make one to work under any light conditions, indoors or outdoors. All we need is fps, we can do the rest, surely?
Yes, we couldn't use ours in the winter even midday for regional competitions, it just didn't register shots.
We've been using a CHRONO-R2 from https://chrono.lmbr.pl/products.html ever since in all weathers with zero problems.
I have a LMBR RA2, £147 from J.S. Ramsbottom. It works in ANY light conditions. Not the cheapest but imho one of the best.