DA Failure Report of OPS TEST #18 and SO's Reponses

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#18.modified:    28 Sep 98  14:30 (tab)

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#18: Comments:
   Wrong dither table was used for this test, may have caused dither time
      and amplitude violations.

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#18.01   NOT-CRITICAL : CLOSED

problem: no dithers in last frames
  The 2nd and 3rd (or more) frames from the end are not dithered.

obsid:  2d191100  2d192300  2d193900  2d194100  2d194900  2d195800
        2d196400  2d1a0100  2d1a1100  2d1a2300  2d1a2900  2d1a3900
        2d1a4100  2d1a4900  2d1a5100  2d1a5800  2d1a6400  2d1a6800
        2d1d2300  2d1d3300  2d1d4100  2d1d4900  2d1d5100  2d1d5800
        2d1d6400  2d1d6b00  2d1e1100  2d1e2300  2d1e3900  2d1e4100
        2d1e4900  2d1e5800  

explanation:
  This is not a problem.  See #20.04.

future:  No change.

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#18.02   IMPORTANT? : OPEN

problem: stim image on first frame
  Stim is not commanded but e-/s indicates stim flash image.

obsid:  2d194100  2d194900  2d195100  2d1a4100  2d1a5100  2d1d4900 
        2d1d5100  2d1e4100  2d1e4900  

explanation:
      Image injector or simulator problem.
      See #19.04 and #20.05.

future: Fixable? 

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#18.03   IMPORTANT? : OPEN

problem: stim image on third and/or fourth or fifth to last frame.
  Stim is not commanded but e-/s indicates stim flash image.  Following
  images usually not dithered.

obsid:  2d196400  2d1a0100  2d1a6400  2d1d6400  
       
explanation: Image injector or simulator problem.
           See #19.05 and #20.06.

future:  Fixable?


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#18.04   IMPORTANT? : OPEN

problem: Last image is commanded stim, but image is not stim.

obsid: 2d196a00  2d1a0900  2d1b0100  2d1d1100  2d1d3900  2d1e0900

explanation: image injector or simulator problem?
           see #19.10 and #20.09.

future: fixable? 

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#18.05    CRITICAL : PENDING

problem: Dither amplitude greater than 21 arcmin.
   This is during survey_lmc.  45<DA<51 arcmin.

obsid: 2d1d5800  2d1e5800  2d195800  2d1a5800  

explanation:
  This could be caused by wrong dither table because this problem disappeared
  after using correct dither table in Ops Test #19 and #20.

future: 
  Double check the next test.  Make sure GSFC uses the correct dither table. 

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#18.06    IMPORTANT? : PENDING

problem: Stim image in wrong place.
  Stim image appears on third to last frame, but commanded stim is at
  last image, and commanded stim does not show stim image.

obsid: 2d1e0100

explanation:  Image injector or simulator problem?
  See Ops Test #19 and #20 failure reports.

future: fixable?

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#18.07    IMPORTANT? : PENDING

problem: w: median e-/sec inconsistent.
  Median e-/s in images vary by 10-50% or more, and are usually negative on
  25 micron frames.  Sometimes negative on 12 micron frames.  Sometimes the
  image is all zero.

obsid:  (most of the obsids)

excuse: image injector problems?  See #19.0 and #20.14.

future: fixable?

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#18.08    CRITICAL? : OPEN

problem: bd: Dithered stim.

obsid: 2d1e5100

explanation: 2d1e5100 is survey_sls. Don't know why the stim flash is dithered.

future: Occurred in Ops Test #19 but not in #20.  Ignore?

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#18.09   CRITICAL? : OPEN

problem: dt: Bad dither times.
  Dither time is 4s with no dither, followed by a 11 arcmin dither with
  0.00 dither time on last frame (which is a dithered stim).

obsid: 2d1e5100

explanation: 2d1e5100 is survey_sls.  Don't know why.  See #18.08.

future: ignore?

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#18.10    CRITICAL : PENDING

problem: dt: Dither time longer than 20 seconds.
  Only on survey_lmc obsids.

obsid: 2d195800  2d1d5800  2d1e5800  

explanation:  Same as #18.05

future: Same as #18.05.

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#18.11   IMPORTANT : CLOSED

problem: Break in time sequence.
  A gap of over 3 hours occurred between 2d1b0900 and 2d1d1100.

obsid: 2d1b0900  to  2d1d1100

explanation: Data appeared later.

future: No time gaps seen in Ops #19.

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#18.12   IMPORTANT : CLOSED

problem: Break in time sequence.
  A gap of over 10 minutes occurred between  2d1a2900 and 2d1a3900.

obsid: 2d1a2900  2d1a3900

explanation: Data appeared later.

future: No time gaps seen in Ops #19.