This directory contains fiber descriptions.  There are two types of
tables, the fiber transmission tables, and the fiber aperture tables.

		FIBER TRANSMISSION TABLE

PARAMETERS:

    The following fiber transmission parameters are used.

          title - Title used for labeling of output.
    description - Multiple lines of text used for documentation of output.
     tablescale - Factor by which to multiply the table values.
       aperture - Default aperture table.

    The default aperture table overrides the default value in the
    spectrograph file.  The program aperture parameter overrides any
    value specified in this file.

TABLE:

    The fiber table has two columns, the wavelength in Angstroms and the
    fractional transmission at that wavelength.  For values in percent use
    a "tablescale" parameter of 0.01.  If no table is given then 100%
    transmission at all wavelengths is assumed.

EXAMPLE

    # title = "Hydra red fibers"
    # aperture = "KPNO/Fibers/redfibap"

    3400 0.0
    4000 0.6
    5000 0.81
    6000 0.86
    7000 0.88
    8000 0.90
    9000 0.92
    10000 0.93

SYNTAX:

    Comment lines begin with '#' and can contain any text and can occur
    anywhere in the file, though normally found at the beginning.

    Parameters are comment lines with the form

	# <parameter> = <value>

    where whitespace is required between each field, <parameter> is a single
    word parameter name, and <value> is a single word value.  A quoted string
    is a single word so if the value contains whitespace it must be quoted.
    Any text following the value is ignored.

    The optional table is a multicolumn list of numeric values.  The list
    must be in increasing order in the independent columns.  Only 1D (two
    columns) and 2D (three columns) tables are currently supported.  2D
    tables must form a regular grid.  The table will be interpolated.
    Extrapolation outside of the table consists of the taking the nearest
    value; thus, a single line defines a constant value for all values of
    the independent variable.  If a "tablescale" parameter is specified
    then the table values are multiplied by this value.


	 	CIRCULAR (FIBER) APERTURE TABLE

PARAMETERS:

    The following aperture transmission parameters are used.

          title - Title used for labeling of output.
    description - Multiple lines of text used for documentation of output.
     tablescale - Factor by which to multiply the table values.
       diameter - Default aperture diameter in mm.

    The default aperture diameter may be overridden by a program parameter.
    However, when the aperture consists of the fiber input then this
    parameter is usually the place where the fiber aperture is defined.

TABLE:

    The aperture table for circular apertures has two columns, the ratio of
    the aperture diameter to the user specified seeing FWHM and the
    fraction of light transmitted.  The first column can also be thought of
    as the aperture diameter in units of the seeing FWHM.  For transmission
    values in percent use a "tablescale" parameter of 0.01.  If no table is
    given then 100% transmission at all seeing/aperture sizes is assumed.

    Aperture transmission tables can be made for various types of profiles.
    However, the most common one would be for Gaussian seeing profiles.
    the transmission values are then the fraction of the Gaussian profile
    passing through the aperture diameter where the independent parameter
    is the aperture diameter in units of the FWHM of the profile.

EXAMPLE

    # title = "Hydra red fiber aperture with Gaussian profile"
    # diameter = 0.31 mm

    0.00 0.000
    0.10 0.007
    0.13 0.011
    0.16 0.017
    0.20 0.027
    0.25 0.043
    0.32 0.067
    0.40 0.104
    0.50 0.160
    0.63 0.241
    0.79 0.354
    1.00 0.500
    1.26 0.667
    1.58 0.825
    2.00 0.937
    2.51 0.987
    3.16 0.999
    3.98 1.000

SYNTAX:

    Comment lines begin with '#' and can contain any text and can occur
    anywhere in the file, though normally found at the beginning.

    Parameters are comment lines with the form

	# <parameter> = <value>

    where whitespace is required between each field, <parameter> is a single
    word parameter name, and <value> is a single word value.  A quoted string
    is a single word so if the value contains whitespace it must be quoted.
    Any text following the value is ignored.

    The optional table is a multicolumn list of numeric values.  The list
    must be in increasing order in the independent columns.  Only 1D (two
    columns) and 2D (three columns) tables are currently supported.  2D
    tables must form a regular grid.  The table will be interpolated.
    Extrapolation outside of the table consists of the taking the nearest
    value; thus, a single line defines a constant value for all values of
    the independent variable.  If a "tablescale" parameter is specified
    then the table values are multiplied by this value.
