I’m having trouble with the shutter of the guide camera that’s integrated in the FW8G-STT filter wheel—after an hour or two of use, it fails to open completely. I’ve seen some forum threads on this, but it isn’t clear to me how to proceed. For context, I’ve been using the camera/FW for a year and a half without problems (mostly). Observations: 1. The artifact has ocurred in the last four sessions, 1-2 hours into a session. There are no error messages. 2. Initially about 30% of the guide camera image is obscured, and in only about half of the exposures. Over the next hour, all exposures become affected and the the entire field is obscured. 3. If I cycle power, the issue resumes immediately. But if I power down overnight and then start the next day, the shutter works well for 1-2 hours before the artifact starts again. 4. It occurs with camera control by CCDOps, or by SGP/PHD2/SGP API Driver. The camera drivers are current, the firmware is ver2.62. 5. With the filter wheel cover off, I see the shutter moves freely. I can physically move it, and it springs back when released. 6. During normal operation there’s a tic…tic as the shutter opens and closes. With the artifact, the opening tic is notably softer. 7. The STT-8300M continues to perform well when this happens, and the green status LED glows/blinks as expected. No other LEDs are on. 8. I see the problem with either SBIG power cable, AC or DC. Also with the camera cooling, or at ambient temperature. Thanks for the help, David
