Psychopsis: sunburn, bugs or virus?
 

Pic 1 is the effected area, it's like the leaf "delaminated". The brown areas do not flake off, no indication of pests of any sort.

Pic 2 is the front of the leaf with the effected area outlined.

The plant was getting about 2-3 hrs. of 3,500 fc of direct sunlight (through a window on a cloudless day), then 1,250 fc of indirect the rest of the day. It now has a filter bringing the direct down to about 2,250 fc. The effected area faced the direct light, no other areas of the plant are impacted, so I'm guessing I burned it.

It's growing well with new leaves, and has a nice little natural keiki.

These are not high light plants. That is sunburn. Where do you live? If you lived in Phoenix the plant would be burnt to a crisp even in a window.

You can minimize heat damage through windows by putting a fan on the plants. The moving air keeps leaf temperature down to ambient room temperature.

I do push my orchids with a lot of light (with fans), have been very successful, but I've burned a few. This is my first Psychopsis so I posted for other opinions, thank you. I live in the north, and with summer light is getting brighter faster than I was adjusting for. Putting up another filter today...

Pushing light intensity doesn't do much beneficial. Extending fall, winter and spring day length in northern climates is more important.

I also live far north (northern Europe) and a couple hours of direct sun is pushing it with Psychopsis. It's fine in the winter, but the rest of the year I would avoid it. When I first moved to my currect home I had to experiment with my south facing windows (only had north/east until then). Mine didn't burn with direct light, but the leaves became severely 'bleached' from excess light. I then started treating it like the other Oncidium types I have: very bright indirect light with ~30-60 minutes morning sun.

A few years back I sunburned the heck out of my Mendenhall 'Hildos.' Had in a south window on a ledge, and forgot to check the sunlight received as fall arrived and leaves fell off the bush in front of window. Resulted in two VERY scorched leaves that I still live with today. Ugh.

Fortunately, yours doesn't look nearly as bad as mine did. And I've also noticed fading of the marking on some leaves since then when I've left it in its summer place too long. It did regain some of the color after being in more appropriate lighting for a year.

Scoot it further away from the light source, and consider yourself lucky for catching it in a timely manner. :biggrin: