Additional light for window

[nross]

I have orchids in a southwest window with afternoon sun.Brooklyn, NY. On the sill itself keep the higher light plants that I put outdoors in the late spring. Behind that is a table I keep mostly Phals. and Paphs. on. They do okay but think they would benefit from some additional light. Attached some photos that show the window and table. Was thinking of suspending a fluorescent fixture above the table. I would like to keep the fixture as high as possible. The table itself can be raised about 8 inches more.
We are on a budget and wanted to know if should use a four bulb fixture with reflector and how close to the plants it should be. As I said, the light is okay and I think sufficient for the sill plants but want to help the others. Any suggestions as how to do this and what bulbs. The first photo is from outdoors looking in. The other shows the table.Probably a pathetic setup but don't have a great many options.