SITCOMTN-148
LSST Camera Electro-Optical Test Results#
Abstract
‘This note collects results from the LSST Camera electro-optical testing prior to installation on the TMA. We describe the CCD and Focal Plane optimization and the resulting default settings. Results from eo_pipe are shown for standard runs such as B-protocols, Dense and SuperDense PTCs, gain stability, OpSim runs of Darks, and Darks with variable delays. We also describe features such as e2v Persistence, ITL phosphorescence in coffee stains, remnant charge near Serial register following saturated images, vampire pixels, ITL dips, and others.
Electro-optical setup#
Run 7 Optical modifications#
hello world.
This section describes run 7 optical changes to the CCOB, projector, etc.
refresh of setup with items the same as IR2 (CCOB, no narrow-beam)
diffuser install
projector
Projector spots#
hello world.
This section describes the spots and rectangles tested with the 4k projector
Projector background
Spots on many amps
Spots on one amp
Optical setup
Dark current and light leaks#
This section describes dark current and light leaks in Run 7 testing.
One of the first tests we attempted with the camera was measuring dark current and sources of light leaks in the camera body.
Light leak mitigation with shrouding the camera body#
Sources of light leak with the autochanger#
After completing the shroud of the camera, we proceeded with several long dark exposures using different filter and shutter conditions to establish our baseline dark condition for testing.
We acquired 900s darks with different shutter conditions and the empty frame filter in place.
We acquired 900s darks in different filters with the shutter open
Shutter condition impact on darks#
Filter condition impact on darks#
Final measurements of dark current#
Reverification#
Baseline characterization#
hello world.
This section describes baseline characterization and reverification
first B protocols and PTCS
comparison to IR2 metrics
new features in any baseline runs?
Camera Optimization#
Persistence optimization#
hello world.
Trying new voltages
impact on persistence
impact on full-well
impact on other parameters
Sequencer Optimization#
hello world.
This section describes sequencer optimization.
No-pocket conclusions
Overlap conclusions
Serial flush conclusions
Thermal Optimization#
hello world.
This section describes thermal optimization.
Background
Idle flush off & it’s stability
impact on other parameters
Characterization & Camera stability#
The final result of B protocol and PTC need to be presented here.
B protocol result and PTC result needs to be summarized here.
Guider operation#
hello world.
This section describes guider operation.
initial guider operation
power cycling the guiders to get to proper mode
synchronization
guider roi characterization
Defect stability#
hello world.
This section describes defect stability.
Bright defects
Dark defects with picture frame
Bias stability#
hello world.
This section describes bias stability.
Typical bias stability runs
dark delay
dark with bias delays
Gain stability#
hello world.
This section describes gain stability.
No temp variation, fixed flux
no temp variation, variation in flux
Temp variation, fixed flux
Sensor features#
Tree rings#
hello world.
This section describes tree rings.
Tree rings without diffuser
Tree rings with diffuser
ITL Dips#
hello world.
This section describes ITL Dips.
Vampire pixels#
First observations#
Vampire pixels were first observed in ComCam observations [need more info to properly give context] - Andy’s study on Oct. 8 - Agnes masking effort
LSSTCam vampire pixel features#
The vampire pixels have distinct features, both on the individual defect level, and across the focal plane
Individual vampire features#
General size
Radial kernel
uniformity
Vampire features across the focal plane#
sensor type
static or dynamic
higher concentrations? Particularly bad sensors?
Current masking conditions#
Bright pixels
Dark pixels
Jim’s task
Analysis of flats#
LED effect
Intensity effect
Analysis of darks#
Previous LED effect
Intensity of LED effect
dark cadence and exposure times
Current models of vampires#
Tony & Craig model
Others?
Serial remnants#
hello world.
This section describes incomplete serial flush.
Background
Mitigation with sequencers
discussion of different clears
Phosphorescence#
hello world.
This section describes phosphorescence.
phosphorescence background
phosphorescence on flat fields
phosphorescence on spot projections
Conclusions#
Run 7 final operating parameters#
This section describes the conclusions of run 7 optimization and the operating conditions of the camera. Decisions regarding these parameters were decided based upon the results of the voltage optimization, sequencer optimization, and thermal optimization.
Voltage conditions#
Parameter |
dp80 (new voltage) |
dp93 (Run 5) |
|---|---|---|
pclkHigh |
2.0 |
3.3 |
pclkLow |
-6.0 |
-6.0 |
dpclk |
8.0 |
9.3 |
sclkHigh |
3.55 |
3.9 |
sclkLow |
-5.75 |
-5.4 |
rgHigh |
5.01 |
6.1 |
rgLow |
-4.99 |
-4.0 |
rd |
10.5 |
11.6 |
od |
22.3 |
23.4 |
og |
-3.75 |
-3.4 |
gd |
26.0 |
26.0 |
Sequencer conditions#
Detector type |
File name |
|---|---|
E2V |
FP_E2V_2s_l3cp_v30.seq |
ITL |
FP_ITL_2s_l3cp_v30.seq |
v30 sequencers are identical to the FP_ITL_2s_l3cp_v29_Noppp.seq and FP_E2V_2s_l3cp_v29_NopSf.seq. All sequencer files can be found in the github repository.
Other camera conditions#
Idle flush disabled
Record runs#
This section describes run 7 record runs.
All runs use our camera operating configuration, unless otherwise noted.
Run Type |
Run ID |
Links |
Notes |
|---|---|---|---|
B protocol |
E1880 |
||
E2233 |
Identical to E1880. Acquired after CCS subsystem reboot |
||
PTCs |
E1886 |
Red LED dense. Dark interleaving between flat pairs |
|
E1881 |
Red LED dense. No dark interleaving between flat pairs |
||
E748 |
nm960 dense |
||
E2237 |
Red LED dense. Acquired after CCS subsystem reboot. |
||
E2016 |
Super dense red LED. HV Bias off for R13/Reb2. jGroups meltdown interrupted acquisitions, restarted |
||
Long dark acquisitions |
E1117 |
||
E1116 |
|||
E1115 |
|||
E1114 |
|||
E1075 |
|||
Projector acquisitions |
E1558 |
Flat pairs, fine scan in flux from 1-100s in 1s intervals. E2V:v29_NoP, ITL:v29_NoPP |
|
E1553 |
Flat pairs, coarse scan in flux from 5-120s in 5s interval.E2V:v29_NoP, ITL:v29_NoPP |
||
E1586 |
One 100s flat exposure, spots moved to selected phosphorescent regions.E2V:v29_NoP, ITL:v29_NoPP |
||
E2181 |
Flat pairs from 2-60s in 2s intervals. Two 15s darks interleaved after flat acquisition. Rectangle on C10 amplifier.E2V:v29_NoP, ITL:v29_NoPP |
||
E2184 |
10 30s dark images to capture background pattern |
||
OpSim runs |
E1717 |
Long dark sequence, no filter changes |
|
E2330 |
Short dark sequence, filter changes in headers through OCS |
||
E1414 |
30 minutes OpSim run with shutter control, filter change, and realistic survey cadence |
||
E2328 |
Flats with shutter-controlled exposure |
||
E1657 |
10 hour OpSim dark run, ~50% of darks were acquired properly |
||
Phosphorescence datasets |
E2015 |
10 flats at 10ke- followed by 10x15s darks |
|
E2014 |
1 flat at 10ke- followed by 10x15s darks |
||
E2011 |
20 flats at 10ke- followed by 10x15s darks |
||
E2012 |
10 flats at 1ke- followed by 10x15 s darks |
||
E2013 |
10 flats at 10ke- followed by 10x15s darks. Interleaved biases with the darks |
||
Tree ring flats |
E1050 |
||
E1052 |
|||
E1053 |
|||
E1055 |
|||
E1056 |
|||
E1021 |
|||
E1023 |
|||
E1024 |
|||
E1025 |
|||
E1026 |
|||
Gain stability runs |
E1955 |
||
E2008 |
|||
E1968 |
|||
E1367 |
|||
E1362 |
|||
E756 |
|||
E1496 |
|||
Persistence datasets |
E1503 |
||
E1504 |
|||
E1505 |
|||
E1506 |
|||
E2286 |
|||
E1502 |
|||
E1501 |
|||
E1500 |
|||
E1499 |
|||
E1498 |
|||
E1494 |
|||
E1493 |
|||
E1492 |
|||
E1490 |
|||
E1491 |
|||
E1489 |
|||
E1488 |
|||
E1487 |
|||
E1486 |
|||
E1485 |
|||
E1478 |
|||
E1477 |
|||
E1479 |
|||
E1483 |
|||
E1484 |
|||
Guider ROI acquisitions |
E1510 |
||
E1518 |
|||
E1519 |
|||
E1508 |
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E1509 |
|||
E1520 |
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E1511 |
|||
E1521 |
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E1512 |
|||
E1513 |
|||
E1514 |
|||
E1517 |