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Hubble Space Telescope
STIS Monitors

General Performance

Read-Noise

The process of reading out a CCD detector results in small amount of unavoidable electronic noise that is present even in exposures of zero length. The amount of this noise varies with the gain and binning used for the read out and also can vary over time. The read noise is periodically measured for all the amplifiers of the STIS CCD (only amp D is used for science operations) using pairs of bias frames. Full frame and binned observations are made in both Gain 1 and Gain 4, with binning factors of 1x1, 1x2, 2x1 and 2x2. Here we provide plots and tables summarizing these read-noise measurements over time. Further details can be found in STIS ISR 2001-05 and STIS ISR 98-31.


Amp Gain Binning
1x1 1x2 2x1 2x2
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4 Table/
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A 1 Table/
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4 Table/
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B 1 Table/
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4 Table/
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C 1 Table/
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4 Table/
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Table of all data used to make tables and plots