Photoshop :: Epson 9800 Laying Down Way Too Much Ink

I use a MacBook Pro to print to an Epson 9800 roll printer.All of a sudden, the Epson is laying down huge quantities of ink, especially when I print onto film (for screen printing). It puts down so much ink, the ink dribbles down the film and drips off the printer, pooling on the floor, until I leap up and cancel the job. What's more, the printer is printing a light-colored background to images that had no background to begin with.
 
Here's the catch: *this only happens in Photoshop.* (I'm using CS 5.1.) If I take the same image file, place it in Illustrator, and print it, it comes out just fine. So the problem lies in Photoshop's print options.