I grow quite a few catts. They like strong indirect light. You can tell if they are getting enough as the leaves will be a lighter green. If they are that dark green then they need more light. I find they need the temps right too. They like warm or at least mine do. I don't know about screens as I grow all of mine outside on a patio and bring them in and out on a metal rolling shelf when too cold or hot. When they fry it is pretty obvious. I recently left a cattelya basket out in direct light (sun moved on me) and two of the leaves turned black in one day. Not good. I've removed them and lovingly shading the last leaf who looks very lonely. Her name is Irene.... pray she gets better lol.