Hi, I have an ST-i bought new about 4 months ago which just stopped working without error. By that I mean, it connects without error, images can be taken, but regardless of expsoure time, auto/no darks, etc. images end up with no signal. The shutter seems unresponsive and can be opened/closed by simply rotating the camera (out of the box behaviour). But now remains this way when powered. Starting the camera no longer makes the ticking noise as the shutter resets. If you open the shutter manually by rotating the camera (let it fall open), then take a dark, the shutter stays open. Rotate the camera to close the shutter and take a light, the shutter stays closed. Even taking a light frame with the shutter manually opened, results in a blank image. (or say 300 or so counts). So it doesn't seem like a shutter (only) issue. I used CCDOps on two different machines with identical results. The camera had been tested when previously working on both machines. Tried two USB cables on both machines and updated to the latest SBIG drivers. No difference. It's looking a lot like a hardware failure. Suggestions are most welcomed. Thanks Eddie astroshed.com