Den phals black mold?
 

I have a dendrobium phal or two with this weird black stuff on canes don't seem to spread to new growth just the old canes any ideas

Looks like mildew to me.

Tell us about your growing conditions.

Wire shelf on east facing side behind an apartment building with two sheer curtains providing sun filter I work 40 plus hours a week so more often than not I air on the side of caution keep them on the dryer side when it gets too cold I planned on moving them in I just wanted to know if this was something I should or could take care of before I do that

The 'air' ----- air-movement could be a consideration. If there's adequate air-movement in the growing area ------ then I think that chance of black stuff growing on stems etc becomes small, or maybe even can stop that kind of thing completely.

On the other hand, if there is a fair bit of air-movement already ------ then assuming it is mould/mildew ---- could maybe spray some mancozeb all around those regions.

Sweet ty I work in a garden center so I have access to almost any chemical I'll get some of that and give it a try this is my first time with a issue usually my systemics do the trick but we have only been at this new place for 3 months and this happened that's why I wanted to get a few more opinions before I made a decision .

What has your humidity been like? Temperatures? Mildew on plants is usually a disease of cool temperatures and low humidity. It can easily be treated by spraying the plant with a good jet of water.

The shoot with black spots looks different. Are you watering enough? Dendrobiums making growth shouldn't dry completely.