Periodically noisy guider images with STT-8300M

Discussion in 'STT Series (retired)' started by Shawn Dvorak, Oct 20, 2016.

  1. Shawn Dvorak

    Shawn Dvorak Cyanogen Customer

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    There's a long-running thread about this problem, but it doesn't seem to be getting any attention so I'll repost my question in a new one. Does 6.13 fix this problem? I updated to the latest firmware and drivers that came out earlier this year but that did not help at all. It's been over well over a year since I reported this problem, and since everything else about 6.11 is great I'm reluctant to pay for an update to fix this long-standing bug unless it's really dead.
     
  2. Owen Lawrence

    Owen Lawrence Retired Staff

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    Hi Shawn,

    Until very recently we were unable to determine the cause, but now we think we know what it is. This issue is in active development at this very moment. V6.13 does not fix it, though we do have a patch that fixes quite a few other problems relating to the SBIG w/AO7 plugin. More work is being done to the general autoguider algorithm, too, but it's a big job and is taking quite awhile to get through. Both of these changes will make their appearance in V6.14.

    - Owen -
     
  3. jerryyyyy

    jerryyyyy Cyanogen Customer

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    Guys, I am running 6.14 Beta 11 and have been searching for a solution for this. Here is some more documentation. The attached excel file is a plot of my guiding when these I call them "Salt and Pepper" guider images show up. See the Offsets? They are both positive and negative (check bottom of file- it is sorted on the offsets column). Notice the corrections that are sent to the mount! Quite a jolt! At least if you could set limits on these, it might help. I can watch these occur in real time monitoring.

    I did notice that the multi-star limits this. I went back to single star because I had filter wheel problems and had to re-calibrate everything after fixing the wheel. I think I have to go back to multi-star but the reality is that the guiding was not much better and probably the eccentricities were worse that the single star on a good night.

    It would be nice if there were some idea of what is causing this? It is indeed a hardware issue. Maybe at least in the drivers or in maxim you could set a limit and not use such bogus data in guiding. [I am saying this twice]....

    Happy Imaging in the New Year :)
     

    Attached Files:

  4. Doug

    Doug Staff Member

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    Thanks for the data - Owen will review next week. In the meantime, please update to 6.16.
     
  5. jerryyyyy

    jerryyyyy Cyanogen Customer

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    Where is 6.16 located? Change log? I am running the Beta so not sure how to install.
     
  6. Doug

    Doug Staff Member

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    Help menu Check for Updates.

    Release notes as always are in the Help.
     
  7. JoshuaHufford

    JoshuaHufford Cyanogen Customer

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  8. jerryyyyy

    jerryyyyy Cyanogen Customer

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    Hi, I upgraded to 6.16 yesterday and the guiding was not affected. Here is the tracking data from last night for a couple images. These were testing images and were 100s Ls.

    Now that I know what the phenomena looks like I sorted on the column, changed the color to yellow at top and bottom to identify the aberrations. I then resorted the file by time. Then I looked back in the file to see what happened. The aberrations hang up the CCD for almost a minute.... the guiding images at 7s images with a 3s filler at the end (1 image/10s given the low PE on my mount and seems to best stabilize guide star scintillations).

    Again seems you could filter out these aberrations in Maxim and never send them to the guider. We are not going to fix the chip.
     

    Attached Files:

    Last edited: Dec 29, 2017

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