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Hubble Space Telescope
FOC Instrument Science Report #096

FOC Instrument Science Report #096       January 28, 1997

"FOC f/48 Wavelength Calibration"
by M. Voit

Abstract excerpted from the report:

This report describes the program undertaken to calibrate
the wavelength scale of the FOC f/48 long-slit spectrograph.
The calibration proceeds in two steps. We first remove the
camera distortion by rectifying the reseau grid in an internal
flatfield image from the same visit. Then we compute the
transformation that takes the observed spectral lines to
their desired positions. Because the camera distortion is
time-dependent, we describe how to make custom calibration
files as needed.