ISIS Documentation

lromakeflat

Create a flat-field image for line-scan, push-frame, and framing instruments

This program creates flat-field images for line scan, push frame, and framing instruments. All input cubes should have the same number of samples; any images in the list that do not have the same number of samples as the first image will not be used. The names of the cube files used to create the flat-field image must be entered using an ASCII file (FROMLIST) with one filename per line (any line beginning with a '#' or '//' is treated as a comment). The specific equation for each camera type is below.

  • Line Scan
  • A frame is a NUMLINES line section of data. The equation for the final single line, single band, flat field file is:
    Mean Calculation:
    Sum( Sum(FrameColumn) / Average(Frame) * ValidPixels(FrameColumn) ) / TotalColumnValidPixels
    Median Calculation:
    Median(PixelColumn(ValidPixel / Average(Frame)))

  • Push Frame
  • Mean Calculation:
    The equation for the final single framelet, single band flat field file is:
    Average( PixelInFramelet1, PixelInFramelet2, PixelInFramelet3, ... )
    Median Calculation:
    Median(PixelColumn(ValidPixel / Average(Frame)))

  • Framing
  • Mean Calculation:
    The equation for the final single framelet, single band flat field file is:
    Average( PixelInCube1, PixelInCube2, PixelInCube3, ... )
    Median Calculation:
    Median(PixelColumn(ValidPixel / Average(Frame)))

Warning: This program creates potentially large temporary files


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History

Victor Silva2016-09-12 Original version, Adapted from Isis version of makeflat.