Measurement made by Boris Gaillard the: 23 - 28 May 2001
Data
reduced by Boris Gaillard and Fabrice Christen the: 05 June 2001
Clock mode: 225kpx/rr/HG/512 Conversion Factor= 0.56412e-/ADU ±0.001261 for 17359.4ADU RMS noise = 3.8122e- ±0.1714 CCD temperature : -120Cº Window area is : X1= 201 X2= 2031 Y1= 14 Y2= 499 Bandwidth 5nm Wav. QE% PRNU rms% Phase= 320 67.9 ±1.9 5.76 7.005287 330 72.4 ±2.1 5.63 6.977772 340 78.3 ±1.5 5.57 6.968654 350 79.6 ±0.78 5.57 6.971289 360 81.9 ±0.81 5.55 6.978639 370 84.6 ±0.83 5.13 6.900652 380 86.9 ±0.86 4.07 6.679676 390 89.4 ±0.92 3.21 6.458753 400 89.7 ±0.91 2.65 6.27593 420 88.6 ±0.89 2.06 6.049998 440 87.9 ±0.88 1.75 5.889302 460 86.1 ±0.87 1.54 5.751379 480 84 ±0.84 1.58 5.802571 500 83.3 ±0.84 1.55 5.793017 520 82.4 ±0.83 1.47 5.743903 540 81.1 ±0.82 1.42 5.709936 560 79.6 ±0.8 1.37 5.680816 580 78.9 ±0.79 1.4 5.717239 600 77.7 ±0.77 1.38 5.709614 620 76.7 ±0.75 1.37 5.712337 640 75.6 ±0.74 1.18 5.553889 660 73.5 ±0.71 1.22 5.603571 680 71.4 ±0.68 1.3 5.674865 700 68.5 ±0.64 1.4 5.757575 720 65.9 ±0.61 1.58 5.885586 740 62.5 ±0.57 1.89 6.070488 760 58.6 ±0.52 1.67 5.935491 780 54.8 ±0.48 1.92 6.077675 800 50.1 ±0.43 1.97 6.103211 820 45.7 ±0.39 2 6.119986 840 41.3 ±0.35 2.19 6.209537 860 36.7 ±0.31 2.08 6.162161 880 31.6 ±0.26 2.33 6.270874 900 26.8 ±0.22 2.56 6.37304 920 21.2 ±0.17 3.13 6.575646 940 14.4 ±0.11 4.73 6.981374 960 11.9 ±0.091 5.75 7.124779 980 7.77 ±0.059 7.11 7.27777 1000 4.63 ±0.035 8.06 7.436955 1040 0.761 ±0.0057 8.38 7.504815 1100 0.09 ±0.00067 12.3 7.76219
Table 1: Measurement of the Quantum Efficiency.
Figure 1: Graphic representation of the QE.
Figure 2: Graphic representation of the PRNU.
In this section you can compare the QE we measured with the testbench and
QE Minimum specification
Typical QE
QE from Marconi
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|---|---|
Figure 3: Comparison between the QE measured by ESO, the QE measured by Marconi, ESO specification and minimum specification. |
Figure 4: Ratio between the ESO measurements and the ESO minimum specification. |
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Special specification |
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|
Wavelength(nm) |
Minimum spec. (%) for 25% of devices |
ESO measurements (%) |
Result |
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350 |
50 |
79.6 |
OK |
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400 |
80 |
89.7 |
OK |
|
650 |
80 |
74.6 |
Under the minimum spec. |
|
900 |
25 |
26.8 |
OK |
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Conclusion: |
No, this CCD is not in the 25 %. |
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Table 2: Minimum specification for 25 % of the CCDs.
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Comparison QE ESO / QE Marconi |
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|
Wavelength (nm) |
QE ESO (%) |
QE Marconi (%) |
Difference (Eso - Marc. %) |
Relative difference (Marconi as reference %) |
Ratio QE ESO / QE Marconi |
|
350 |
79.6 |
64 |
15.6 |
24.4 |
1.24 |
|
400 |
89.7 |
83.6 |
6.1 |
7.3 |
1.07 |
|
500 |
83.3 |
81 |
2.3 |
2.8 |
1.03 |
|
650 |
74.6 |
73.4 |
1.2 |
1.6 |
1.02 |
|
900 |
26.8 |
26.5 |
0.3 |
1.1 |
1.01 |
Table 3: Difference and relative difference between ESO measurements and Marconi.
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|---|---|
Figure 6: Graphic representation of the difference and the relative difference. |
Figure 7: Ratio between the ESO measurements and the Marconi measurements |
For the flat field we use three wavelengths, 350nm, 600nm and 900nm. For each wavelength we make two images, high level (45000 ADU) and low level (1000 ADU).
350nm (UV), bandwidth 5nm |
600nm, bandwidth 5nm |
900nm, bandwidth 5nm |
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High level |
Low level |
High level |
Low level |
High level |
Low level |
Table 4: Flat field for three wavelengths.
The time exposure, for the long dark exposure, is 3600 seconds.
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Bias |
Long exposure dark image |
|---|---|
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Table 5: Bias and dark.
Left readout port Clock mode: 225kpx/rlrl/HG/512 Conversion Factor= 0.58458e-/ADU ±0.002404 for 20370.4ADU RMS noise = 3.8369e- ±0.1615 right readout port Clock mode: 225kpx/rr/HG/512 Conversion Factor= 0.56471e-/ADU ±0.001898 for 20560.1ADU RMS noise = 3.8167e- ±0.1679 Left readout port Clock mode: 50kpx/rlrl/HG/512 Conversion Factor= 0.63132e-/ADU ±0.002841 for 19995.9ADU RMS noise = 2.9115e- ±0.2887 Right readout port Clock mode: 50kpx/rlrl/HG/512 Conversion Factor= 0.60978e-/ADU ±0.002577 for 20117.5ADU RMS noise = 2.5617e- ±0.1343
RMS non linearity (%) = 0.4 Peak to peak non linearity (%)= 1.2
Figure 5: Error of linearity
Figure 6: Residual non linearity.
Exposure time (s) = 3600 Dark current : 0.96 ± 0.02 ADU/hour/pixel Dark current : 0.53 ± 0.01 e-/hour/pixel
High level (Around 25000 ADU) Horizontal CTE = 0.999997 Vertical CTE = 0.9999995
In this section we expose the hot pixel, the dark pixel, the trap and the very large trap we found.
A hot pixel provides a signal of > 60 e- / pixel / hour.
Result: 365 hot points.
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Position |
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X= |
Y= |
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Total hot pixel: 365 |
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Table 6: Position and images of the hot pixels.
A dark pixel is one with 50% or less than the average output for uniform intensity light level, measured with a flat field level around 500 photo-electrons.
Result: 134 dark pixels detected.
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Position |
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Total hot pixel: 134 |
Table6: Position and images of the dark pixels.
A trap is defined as a pixel that captures more than 10 electrons, measured with a flat field level around 500 photo-electrons.
Result: Not available
A very large trap is defined as a pixel that captures more than 10 000 electrons, measured with a flat field level around 90% of full well capability.
Result: Not available.
A bad column is 10 or more contiguous hot or dark pixels in a single column or a very bright pixel or a very large trap.
Result: bad columns.
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Position Image |
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|
X= |
Y= |
141 107 600 1121 1122 1123 1290 1427 1990 1995 |
10 550 1434 2875 2875 2875 1020 2609 3576 1851 |
Total bad columns: 10 |
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Table 7: Position and images of the bad columns. The values in the table are in ADU. Conversion factor: 1.1 e-/ADU
Here is a summary of cosmetic defects:
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|
Hot pixel |
Dark pixel |
A very bright pixel (a) |
Trap |
Very large trap (b) |
Sup. 10 contiguous pixels (c) |
Total bad column (a+b+c) |
|---|---|---|---|---|---|---|---|
|
ESO |
365 |
134 |
/ |
/ |
/ |
10 |
10 |
|
Marconi |
244 |
1 |
7 |
7 |
6 |
14 |
|
Table 8: Summary of cosmetic defects.
Be careful, in the ESO test report we didn't include the very large trap in the total bad column because for this CCD we couldn't measure this parameter.
Back to the overview page ESO Test Reports for the OmegaCAM CCDs
