Resolved AO-X Problem?

Discussion in 'Guiding and Adaptive Optics - StarChaser and AO' started by mike m benjamin, Aug 16, 2021.

  1. mike m benjamin

    mike m benjamin Cyanogen Customer

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    I picked up a used STXL11k/ FW8G/AO-X recently, I have this mounted on my pier to a CEM120, /Meade 12" F8 (2438mm) and a Moonlight Litecrawler. The polar alignment is excellent and just checked. The problem is I keep getting oblong stars in dec, even running bin 2x. Doesn't seem to matter how many hz I get the AO to operate at either. Running current 6.27. I can see the issue in the correction box, the second number will occasionally ( once a minute?) jump to (2.4-3.0) for a few seconds before it drops to .2-.4. To have any effect I have to run crazy aggressiveness (17-18) which hurts the ra. In the past I've run on the same equipment a STT 8300 and 3200 with an AO-8 with no issues. I should add I had no issues during calibration.
     

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  2. Colin Haig

    Colin Haig Staff Member

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    Hi Mike, I'm going to ask @Brian Brown to chime in - he has been tweaking AO operation a bit.
    The scope's an ACF, right?
     
  3. mike m benjamin

    mike m benjamin Cyanogen Customer

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    Yes, it is an acf model.
     
  4. Colin Haig

    Colin Haig Staff Member

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  5. mike m benjamin

    mike m benjamin Cyanogen Customer

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    I'll give it a try Colin, the weather should cooperate tonight.
     
  6. mike m benjamin

    mike m benjamin Cyanogen Customer

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    No luck with my issue Colin. The plug in had no effect. I did notice tonight during calibration of the AO, I always got the message " Star moved less than five pixels in the Y direction". I tired different stars, binning, exposure lengths etc., no difference. While tracking with the AO I noticed as well the second number (Y) always would move between 0 and 100%, if it started at 0% the numbers would rapidly rise until it hit 100, stay there for a couple seconds and do the opposite, rapidly descend to 0%.
     
  7. Colin Haig

    Colin Haig Staff Member

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    That makes me suspect a configuration or hardware issue.
    Does regular guiding move properly in Y+/- (normally that's declination) ?
    e.g. if you switch from SBIG w/AO to SBIG Universal, and do regular guiding
    Often when we see that, it's incorrect wiring on the guider cable (ST-4 port). (e.g. straight instead of flipped RJ12).
     
  8. Colin Haig

    Colin Haig Staff Member

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    I should add it might be a good idea to run the CCDOps exerciser function on the AO-X to make sure it is moving in both axes properly. The Y side may be "stuck" mechanically or a damaged voice coil / broken wire could be preventing it from pulling in on one side.
    The exerciser will allow you to test both axes. It should thunk with some authority. Worst case, remove from telescope, and bounce a laser pointer beam off the optic, and see if the reflected beam moves.
     
  9. mike m benjamin

    mike m benjamin Cyanogen Customer

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    Colin, I have the mount controlled using "telescope", not guider relays. I didn't try regular guiding with this set up. Although during mount calibration a very nice L pattern is made. I have exercised the AO in ccdops with the camera sitting on my bench so I could watch the lens move, it moves fine.
     
  10. Colin Haig

    Colin Haig Staff Member

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    Last thing: If you launch SBIG Driver Checker, can you confirm that it has sbigudrv.dll 4.99 build 7, and not something else like 5.0.2.0.
     
  11. mike m benjamin

    mike m benjamin Cyanogen Customer

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    Yes somehow I reinstalled 5.0.2.0. I rolled it back to 4.99 build 7. I'll give it another try tonight, thanks.
     
  12. mike m benjamin

    mike m benjamin Cyanogen Customer

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    Colin trying it out now, really don't see much of a difference. It took many try's but I did get to calibrate the AO, although it still not correcting correctly in the Y axis, moving regularly between 0 and 100%. I also see when calibrating the drive the box will often lose the star. I did notice that the AO tracking speed after I did it to calibrate where much lower than the manual says it should be, X-34 and Y-15.
     
    Last edited: Aug 18, 2021
  13. Colin Haig

    Colin Haig Staff Member

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    Ok, thanks for the feedback. @Brian will have to look at this when he's back on Monday.
     
  14. mike m benjamin

    mike m benjamin Cyanogen Customer

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    It might be comparing apples to oranges but I seem to remember with my Ao-8 the tracking speed number in the X and Y were in the 50-60 range. Also, I recall while doing the calibration procedure with the AO-8 a cross being formed, no cross to be seen while trying the same with the AO-X.
     
    Last edited: Aug 19, 2021
  15. mike m benjamin

    mike m benjamin Cyanogen Customer

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    Colin, I resolved this issue. Not the software or the AO-X fault, it was (is) my mount. My guiding without the AO is bad as well, far worse than before. I put the CEM120 into the pier a number of times over the years and the latest time did some damage internally that I need to get repaired.
     

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