Strange Oncidium yellow black spots on leaves issue

[braxtonds]

For me, last year was pest issues, this year are leaves issues. Sorry picture heavy post incoming.

It's time for me to begin to make room in the next few weeks to bring all my orchids back inside for the winter. This year I've expanded my collection to include many different types that I've never grown before oncidiums and their hybrids. These soft leaved types are bringing me issues that I need help on.

This is probably my worst offender. I began seeing these spots all over the new growth and they are driving me insane. I've tried Physan but I have to admit that I do not know many of the signs of bacterial or fungal infections and have been searching the forums for help.







These are photos from 3 different plants, all next to each other, all with the same issue. They all receive similar light, which is fairly high, full to dappled light till around 2pm. It is affecting only the new growth leaves, the older leaves are fine.

I need help to identify if its too high light, or a fungal/bacterial issue. It was also suggested by a friend that it might be a fertilizing issue. I normally use time released fertilizer to ease my watering regimen. But this year I used a different brand than I normally used to, Osmocote, 19-6-12. I used it mainly because I was given a large amount of it, should I get something else? Or did I put too much in the mix?

Also, these spots showed up on my C. Green Emerald 'Queen' sitting right next to these plants. Is this related? I fear I might have a serious cross contamination issue and would love some expert advice. Thanks!