I have a (black and white) handout from Dr. McMillan's talk at the Tamiami show earlier in the year about Orchid Diseases..could it be Pseudocercospora leaf spot? If so , the treatment would be Thiophanate methyl, Azoxystrobin, Dithane, Fungo or Clearys 3336.. another black and white photo that looks similar is of chemical stress..I'll have to dig out the DVD that he gave me with the color photos on it!
