PBL: we have found a problem with slopes reordering...
We close a loop with LGSW only REC: 20151209_213200 w/o disturb.
Gains were 0.3 on all modes. Since we're closing the loop manually, w/o foreman config, the proper gain values and RECs are not displayed.
We load a disturb taken from FLAO directories, equivalent to 0.8" in double pass, 1kHz:
GOX finds a bug in the
numSubapsReadyVec that controls the number of subaps that are ready to be computed for slopes.
Another problem was due to the "isCameraRotated" setup: the dummy= False flag screws up all the
BCU configuration, so we force it to True...
After this debug we go back to IM acquisition, starting from scratch.
We select
CoG subaps: 20151019_233800
# modes |
IM REC |
IM |
LGSW REC |
COMBO REC |
10 |
- |
20151210_203840 |
- |
- |
10 |
- |
20151210_211144 |
amp calibrated x0.5 |
- |
10 |
- |
20151210_201057 |
shell crash, we move to x1 modal amplitudes |
- |
HEXA |
4.87 |
-0.03 |
7.8 |
215 |
-57 |
We try to home the swing arm, and to deploy it again, we are inside the LGSW
FoV...
PCT ON SX:
TN |
Plot |
('20151210_223719','20151210_23223851') |
|
Debug of slopes ordering
We acquire a serie of dark frames and we compare the slopes computed from these frames with the ones coming from
BCU: we can match slopes #11 with frame #0.
-> slopes reordering was wrong, "subapPixelPointer" we were starting to compute slopes from columns close to center wile the pixels are read starting from frame edges. This was causing the central stripe in the IM display shift...
We double check for the same effect in the DX system: TNs: 20151211_003905, 20151211_004620. Analyzing slopes #31 and the ones evaluated from frame #0 we have 10^-8 residuals w/o software modifications...
We also check for this effect using old snapshots: we consider data from 20150703_232010: just blue slopes are 0s while yellow and red are 0.3-0.6 level...
We acquire new data: 20151211_023107 it is good, subtractions gives all 0s.
Probably the analysis of old snapshots was wrong, indeed we had a dummy subaperture added at the bottom of the frame and the PC slope computer handles differently this subaperture wrt the
BCU. The PC slope computer adds this subaperture at the end of the subap list while the
BCU indexes the subaps accordingly to their column position. Hence the comparison is wrong.
--
MarcoBonaglia - 11 Dec 2015