spots on leaves

[Earthsong]

Hi,
I recently bought a Burrageara Nelly Isler (between flowerings to minimise postal damage) as companion for my Phal. They are in my bathroom on a North facing windowsill. After a couple of weeks I notice some brown spots and some "transparent" on the Burrageara. Could this be too much light/water (it also has a "pleated" leaf)? Or have I got a sick plant, and if so, how do I help it? Meantime, I notice the aerial roots on my Phal have dug themselves into the pot and are now green. The plant looks strong, although several blooms have dropped (after 2 months). Is this ok?
Also can you advise if a "daylight" bulb will help in winter, as my house gets quite dark? Thank you

[mayres]

North facing windows for us in the northern hemisphere are the least preferable directed windows to grow orchids - in general not enough light. Pleated leaves are usually caused by not enough water and/or humidity. Both of your plants are going to "sulk" with not enough light during the winter months - but especially miss nelly. A supplemental light would be a great idea if you have not much natural light - since you will need to get it fairly close you might want to consider a good strong compact fluorescent (efficient and little heat to be concerned with). Enjoy!

[Earthsong]

Many thanks. I will move them to face south in winter, but was worried about sunburning them during the summer months.