Linearity

I made a series of images using Fowler sampling at different exposure times to calculate the linearity of the chip. Fitting a series of full frame means with maximum of 9000 DN with linear and quadratic fits we find: 
signal=244 + 344 t            20DN rms residuals
      =228 + 343 t -.38 t2    1.2 DN rms residuals
Shows that there is a downward saturation term of fractional percent value.

It also shows that there is an offset of 0.66 seconds in the exposure time. This is consistent with the read time of .656 seconds.

Saturation

Looking at higher signal levels we see the following

The maximum saturation level of 23,000 DN corresponds to 667,000 electrons. The reset voltage at the time was 0.75V.

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Last Revised September 5, 2000