Thanks. They are in full sun outside my southern window. Hanging on fire escape railing facing east. so they get full sun from morning to mid afternoon.
The dendrobium has some sunburn marks so does my Ansellia africana, but mostly on old leaves. I have some plants on the roof which is always breezy and sunny and with the black tar and metallic adjacent roof really hot and bright. I put sugarcane and hot peppers there and Arundina graminifolia.
I think the Vanda may need more fertilizer. I usually just water it with the pump sprayer.

Maybe will add some nutricote-type pellets. But I have 16-3-14 slow release. Fert I use is better gro 15-31-15. I wonder if the media is loose the fert may not stay there long enough.