Hi, a few years ago when I just got started with orchids I had ago similar problem , now I with as only using natural light though.apparently it easy ago fungus that with as as spreading a got the time and after talking to some fellow orchid growers it learnt they had the same problem.it with as as as in our rainy season.anyways I learnt about Phyton 27 and it has proven to be very effective.now I was also thinking about the light but think light damage would not be so spotted.do you use any kind of spray regime with your plants? Velleta

That message was posted incorrectly.my point is maybe you have a fungus problem.i use phyton 27 and has had good results.do you use a regular spray regime on your orchids? Velleta

Did you mist them in direct sunlight? Water droplets can magnify the light and cause burns if it's hot enough.

I have seen that when a sucking bug like scale was on the exact other side. Show a picture of the bottom side of the leaf.