TopBottomHotWarmMaps
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EIS continues calibration operation (eg. REGCAL071/REGCAL072) to generate hot and warm pixels maps for EIS_PREP routine use: e.g. to mark the hot/warm pixel positions and smooth the values on those positions.

The hot/warm pixels maps are distributed with SolarSoft under hinode/eis/data/cal branch.

Before EIS launch, the CCD read-out section was assumed in the middle 512 rows of the CCD. That means EIS_PREP only needs hot/warm pixels maps of middle section of CCDs.

However, in post-launch phase, the top and bottom of the CCDs were introduced to cover whole CCDs area (ie. Y-axis: 0-1023 rows, X-axis: 0-4095 columns). Thus hot/warm pixels maps for EIS CCDs have been generated accordingly as top and bottom maps (in detail: REGCAL072 study for top of CCDs and REGCAL071 study for bottom). The EIS_PREP routine has also changed in order to use top and bottom hot/warm pixels maps.

The following paragraphs are a little bit deep in details. If you don't know what is talking about, that's fine, just ignore it and use EIS software as usual. But in case you are interesting in this topic, here are some technical descriptions:

The EIS camera electronics do not readout CCD row 0 in the y-direction (this is due to how the electronics work, row 0 is always discarded), so for the bottom of the CCDs EIS camera readout from row 1 to row 512 (inclusive), and for the top the camera readout from row 512 to row 1023 (inclusive).

So we can see there is an overlap at the 512th row, ie.:

Bottom half: row 1 -- row 512
Top Half: row 512 -- row 1023

"The overlapping row (512) is there because the MDP requires that data to be a multiple of 8 in both the X and Y directions. Rows 1 to 511 is not a multiple of 8, hence we have to read rows 1 to 512 (inclusive). For the top half we must read 512 for 512 (i.e. rows 512 to 1023), hence the overlap in row 512."

-- Jian Sun (2008-10-17)