Small orange blisters on Den spectabile

[MrsSky]

Hello,
I am having problems with another dendrobium. It is my large spectabile. I noticed some small orange blisters on new leaves today. I cut them off and sprayed the plant with a sulfur based fungicide. I checked Orchid Species Culture Dendrobium by Baker and Baker and it seems to be a form of rust?
I did let the night temp drop to 60 for 2 nights but it was dry (since this leaves were new and perfect just a few days ago I think that it is the cold). I have had a problem with a black spore fungus since I purchased it. Could the blisters be a part of the the fungus cycle?
I am going to try to read through the pathogen section at the back of the Baker book tonight. Any help is appreciated.

[WhiteRabbit]

Hmm ... my spectabile gets down into the 50s at night, and haven't had issues.

Hopefully someone can help out!
If you can post a pic or two, it may help others identify the problem.

[AussieVanda]

There are many types of rust. The ones I mostly encounter are as a result of warm humid air with poor circulation. They are not on my orchids but occasionally on my frangipanis. The leaves are removed put into plastic bags and then tied off and left in the hot sun all day. Do not compost them. I then treat the plant and foliage with copper based applications.

[MrsSky]

Thank you for the advice. I cut all of the small blisters off and I have not had anymore pop up. I'm keeping it quarantined for now.