New FW8G-STXL black frames

Discussion in 'Filter Wheels' started by letteri, Jun 17, 2017.

  1. letteri

    letteri Standard User

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    I have a new FW8G-STXL, and I am getting black frames (ADU = 0 across all pixels).

    The issue seems similar to the one in this post:

    http://forum.diffractionlimited.com/threads/new-fw8g-stxl-guider-not-working.2827/

    I have tried all of the Maxim DL 6 settings recommended in that post, and am testing with a direct connection to the camera for both power and USB. I have also tried swapping the HDMI cable with one that I know works. And I have tried all the combinations of binning and auto dark on/off.

    I can also verify that the autoguider shutter is working.

    FYI, these same settings work fine with my FW8G-STT.

    How do I proceed from here?

    Cheers,
    Joe
     
  2. Tim

    Tim Staff Member

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    Please zip and send us your "Settings" folder located in "My Documents/MaxIm DL 6", so we may see what options you have set.
     
  3. letteri

    letteri Standard User

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    Setting folder attached.
     

    Attached Files:

  4. Tim

    Tim Staff Member

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    On the "Setup Camera 1" window, ensure you have "External Remote" set as the guide camera.
     
  5. letteri

    letteri Standard User

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    Yes, I have tried setting the guide camera to External Remote, as per the recommendations in the earlier post that I was following. If the settings file indicates Internal, it would be because I tried both settings and that was the state that I left it in.

    By the way, on my FW8G-STT, it doesn't seem to make a difference if I set it to Internal or External Remote. Both settings work. Does the FW8G-STXL have a different logic than the FW8G-STT?
     
  6. letteri

    letteri Standard User

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    Anything on this?
     
  7. Tim

    Tim Staff Member

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    They should be very similar.

    Just so I am clear on what is happening, if you directly swap the STXL for the STT filter wheel without changing any setting, STT works, but the STXL filter wheel does not?
     
  8. letteri

    letteri Standard User

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    Correct. The STT works, but the STXL filter does not. The shutter is triggering, but the images coming out are black.

    I received some instructions from William B on how to completely re-install the drivers, related to the memory problem I am having, so I am going to try that next and see if it affects the STXL filter wheel as well.
     
  9. letteri

    letteri Standard User

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    I did a clean reinstall of all drivers, and I can confirm that I am still getting black frames out of the STXL filter wheel. The STT filter wheel has no problems with the same settings (guider set to External in Maxim DL 6).
     
  10. letteri

    letteri Standard User

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    Forgot to mention that I also tried swapping the HDMI cable from the STT-8300, but the problem was still there.
     
  11. Tim

    Tim Staff Member

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    Have you tested the filter wheel with CCDOps software to see if it is an issue with MaxIm DL?

    To eliminate the STXL HDMI port as a cause, have you tried taking a guider image using your FW8G-STXL, but plugged into your STT?

    Are the images black but contain data, or is it a zero data frame? Can you send me a FITS guider image to examine?
     
  12. letteri

    letteri Standard User

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    I have tested with Maxim DL and TSX, but CCDOps is not working for me. The images are zero black in both cases. Attached is an example taken with Maxim.

    I will try to plug the FW8G-STXL into the STT to see if that works.
     

    Attached Files:

  13. William B

    William B Cyanogen Customer

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    How are you testing the camera Joe?

    When I look at your image in Fits Liberator and PixInsight using image analysis tools I see a 100% saturated frame. In Fits Liberator a 100% saturation displays as white, in Maxim and PixInsight it displays as black which is normal when all pixels have a max value.

    When I test my cameras off the telescope I use the pinhole lens method to cut down the light, place a piece of aluminium kitchen foil over the camera optical port and secure with a rubber band etc, make a pinhole in the foil at the centre of the camera optical port then take daytime exposures with the camera pointing at a brightly lit scene. With auto dark disabled, it usually produces some kind of blurry image with exposures in the 0.5 second range.

    William.
     
  14. letteri

    letteri Standard User

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    I have the camera covered for these tests, as I am only trying to produce noise to verify that some signal is being sent out of the autoguider.

    I usually inspect the images with CCDStack, which in this case is reporting zero ADU because it is automatically subtracting the pedestal that got added to the image.

    Here is a dump of the raw image data from the FITS file:

    array([[100, 100, 100, ..., 100, 100, 100],
    [100, 100, 100, ..., 100, 100, 100],
    [100, 100, 100, ..., 100, 100, 100],
    ...,
    [100, 100, 100, ..., 100, 100, 100],
    [100, 100, 100, ..., 100, 100, 100],
    [100, 100, 100, ..., 100, 100, 100]], dtype=uint16)
     
  15. William B

    William B Cyanogen Customer

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    Joe,

    Looking at the fits header it states a simple auto dark was subtracted and that -100 was the correction to add for zero based ADU.

    What is the image like when simple auto dark is disabled?

    I am wondering if the Auto dark is actually 100 for all pixels.
     
  16. letteri

    letteri Standard User

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    With simple auto dark disabled, the images are all zero ADU.
     
  17. letteri

    letteri Standard User

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    Tim,

    I have tried plugging the FW8G-STXL into the STT, and I still get zero ADU from the autoguider.
    In fact, it is worse than that, in that I have also tried plugging the FW8G-STT into the STXL, and that also gives me zero ADU.

    So here is the matrix:
    STT into FW8G-STT : Autoguider is OK
    STT into FW8G-STXL : Autoguider is zero ADU
    STXL into FW8G-STXL : Autoguider is zero ADU
    STXL into FW8G-STT : Autoguider is zero ADU

    Do you have any idea how this could be happening? To me, this seems to imply that the HDMI port on both the STXL and FW8G-STWL are bad, but that seems highly unlikely. Is there any other way to test those ports?

    I ran all these configurations and got the same results using Maxim DL 6, TheSkyX Pro, and CCDOps for OS X. I removed and did a clean install of SBIGDriverChecker64 and all SBIG drivers before running these tests. I also did a clean install of CCDOps for Windows, but it still crashes when connecting to either camera. I also powered the cameras off before switching the connections. AO was bypassed for all the tests.
     
  18. Tim

    Tim Staff Member

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    As William B pointed out, your image is saturated....not simply empty or blank. So it does contain data from the sensor...it's simply saturated.

    So you are certain there are *zero* light leaks during testing? Does reducing exposure time to, for example, 0.2 seconds do anything?

    This is very unlikely. And the fact that the STT filter wheel works with both STT, and STXL cameras essentially confirms that.

    CCDOps has been around for a lot of years. These kinds of bugs have been resolved years and years ago if there were any...so crashing when connecting typically indicates a problem with Windows system files, or driver problems. The only thing I can recommend here is try a different PC. Budget USB hubs are also known to cause crashing in some software. If you are using a USB hub, try bypassing it for testing.
     
  19. letteri

    letteri Standard User

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    If by saturated you mean all pixels = 65535, then which image are you referring to? I only see zero or 100 ADU in the images that I sent, because some of them had the auto pedestal turned on. In one of my responses above I loaded the images with astropy and dumped out the numpy array to verify this.

    I did another series of tests last night with all four nominations of STT and STXL to FW8G-STT and FW8G-STXL. For each one, I did an exposure of 0.01 secs with everything absolutely covered (no light leaks). And then I did a series of 10 second exposures with the covers off and a flashlight shining directly on the autoguider sensor. That should produce a saturated image. The tests were done using Maxim DL 6 with autodarks and pedestal turned off.

    The only combination that behaves as expected is the STT to FW8G-STT. At 0.01 sec, the image has noise centred around 1000 ADU; and at 10sec all pixels are fully saturated at 65535.

    The STXL connected to either filter wheel only produced images with zero ADU, even at 10 sec exposure with a light shining on the autoguider.

    Now I did see something different from the STT connected to the FW8G-STXL. The last time I did this test, I got zero ADU for this combination as well. But in the current test I am getting noise centred around 100 ADU. So thinking that this looked promising, I took the cover off and did the 10 sec exposure with a flashlight shining on the autoguider. But I only got the same low-level noise pattern. That made no sense to me, since I was watching the shutter open and shining a light directly on the autoguider, but there did not appear to be any signal gain.

    Regarding your comment about CCDOps, yes I am willing to scrap this computer and try a new one if that would help. But as I mentioned in my last post, I did try a fresh install of CCDOps Lite on a Mac, and got the same results.

    All these tests are done with a direct connection to the PC, using the USB cables and power supplies that came with the cameras. No extenders or hubs.
     

    Attached Files:

  20. Tim

    Tim Staff Member

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    The symptoms surrounding this issue are confusing and inconsistent. I can not make sense of it. The only other thing I can think of that may cause this is the HDMI cable is not plugged all the way in. Otherwise, it must be a hardware component issue, and you should contact Bill Lynch in repairs, and he should be able to help:

    --------------

    Bill Lynch – SBIG Service & Repair Center

    3769 Constellation Road, Unit D
    Lompoc, CA 93436
    Bill Lynch – email
    Phone: (805) 308-6979

    Note: Please contact our authorized service & repair center for an RMA number prior to returning your equipment.
     

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