ALFOSC CCD8 linearity with ccd3-controller
The x-axis shows the signal level in ADUs and
y-axis the "linearity residual" (LR).
The horizontal dashed lines show the +-1% level of non-linearity.
The data was taken August 26. 2011 using the beta-light source.
This indicates that the system is linear (better than +-1%) up to
~350-400 kADUs (full well= 150ke-/pixel, 459 kADU/pixel).
The "linearity residual" (LR) equation:
LR=100(1-\frac{S_M(DN)/t_{EM}}{S(DN)/t_E})
where LR is the linearity residual at a specific signal level (%).
The variables S(DN) and tE are the measured signal and exposure time
(seconds). The tEM is the exposure time required to produce
a signal (sec), SM at mid-scale in the plot (DN) [Taken from
"Scientific Charge-Coupled Devices" pp 117 by James R. Janesick,
SPIE press 2001].
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