Hi, about 15% of images recorded last night show a dark band across the top with a bright band immediately below (see uploaded screen capture). These bands are in the same place in each affected image. The rest of the image seems fine. This has appeared since starting to guide with the self guiding cover on a FW8G-STT filter wheel. I'm using TheSkyX pro to control both the STT-3200 and guide cameras. Any suggestions as to what the problem is and how to fix it? Cheers, Mark
Hi Mark, while you wait to hear back from the Diffraction folks, there's a couple things that might help. First off, suggest you might want to post this over on the Software Bisque forum. Are you using TSX Pro latest daily build? eg 10.5.0 11360 on Windows? You might want to download the latest SBIG Driver Checker, run that, check for driver updates, and check the camera firmware tab for updates too. Have you tried using CCDOPs or MaxIm to control that camera - do you get the bars? I'm sure other folks will weigh in.
Uploading a FITS image would be helpful. I see you have MaxIm DL... does it occur if you run the camera with it? Or CCDOPS? That will help narrow down the source of the problem.
Hi Doug, FITS image attached. Last night I collected 105 images without autoguiding and all were good. Then I recorded several hundred more images with autoguiding and about 25% of them had the dark and bright band. I'll try MaxIm DL tonight if its clear. However I haven't been able to get MaxIm DL to control my paramount MX+, which is why I've been using TSX. So I'm not sure if I'll be able to test the autoguider. Cheers, Mark
Hi Colin, I currently have TSX 10.5.0 11086 so I'll update the daily build. The Software Bisque site seems to be down at the moment though. I'll try your other suggestions when I go out to the observatory later this afternoon. Cheers, Mark
Hi Doug, the attached image was from the same set as the previous image, but does not have the artefact. I couldn't test with MaxIm DL last night. I'm going to be away from home for the next week or two so testing will have to wait until April. Cheers, Mark
Okay, so below the artifacts the images are consistent - same hot pixels, same average level and background noise, and same sensitivity. This suggests some large upset happened to the analog chain at the start of readout, and then it settled out after a while. I'm not sure what the cause is yet. It might possibly indicate that an improper command sequence was sent to the camera. Do I understand correctly this only happens while autoguiding? Please let us know the results of your testing when you return. It would be really helpful to determine whether this is specific to a particular software or not. If it is then we can probably use logging to narrow things down.
Then it could be caused by improper sequencing. The guider needs to be stopped while the main camera is read out.
If you are not aware there is another thread running over on the Software Bisque forum at this time showing exactly the same image artefact problem only with the SBIG STT1603ME and STT 8 pos self guiding wheel, so different main camera to you but same combined filter/guider. The link to the Software Bisque thread is below though you will need to log in to the SB site to read it, the SB user name of the OP for that thread is ’njscope’, first name Kevin. http://www.bisque.com/sc/forums/t/32138.aspx
