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3.1.3 Converting RDAF Format Files to FITS Format

  To convert an RDAF format RAW, PI, FES, or LBL(S) image file to an IRAF-compatible FITS format, you may use IMFITS:


FILE Input file name, without extension. Both .DAT and .LAB files must exist.
h If desired, the FITS header for the new file can be output as a string array.
eps If this keyword is set, the quality flag array will be included as an image extension, otherwise it is not included. This option is only available for LBL and PI files since raw and FES files have no quality flags.

This procedure writes two files: IMAGET.HHH (header only) and IMAGET.FIT (both header and data).

There is a procedure called EXTFITS that can convert MELO and MEHI spectra to three different FITS formats, one of which is compatible with IRAF.

EXTFITS,'IMAGET',ORDER,mode,h  IMAGET Input file name, without extension.

ORDER Order number(s) to be extracted. This should be 1 for MELO files since low dispersion files do not have multiple orders. For MEHI files, ORDER can be a vector with up to 60 entries (e.g., [89,90,91]). For mode 3 only one order is written; additional orders specified are ignored.
mode This should be 1, 2, or 3. The default is 1. The modes are:
  1. Creates a binary table with the following fields for each order requested: M (order number), NPT (number of valid data points--orders are padded with zeroes due to variations in length of orders), W (wavelengths, not linearized), G (gross fluxes), B (background fluxes), N (net fluxes), A (Calibrated fluxes--assumes an exposure time of 1 second), E ( $\epsilon$ data quality flags).
  2. Similar to mode 1 except that wavelengths are linearized and replaced in the table by W0 (starting wavelength) and DELTAW (increment).
  3. Wavelengths are linearized, and calibrated fluxes (assuming exposure time of 1 second) are written as a primary array. This is the IRAF compatible mode.
h If desired, the FITS header created can be output as a string array.

The output file IMAGET.FIT is written to the same directory as the input file. Note that for modes 2 and 3 (which linearize the wavelengths) the wavelengths in the input file must be monotonic. Thus, the vacuum to air discontinuity in the MEHI file at 2000 Åcause problems.

For high dispersion data processed prior to 1990, the calibrated data is not included in the MEHI file, and the ripple corrected net fluxes will be read and written out instead. Unlike IUESPEC, which reads the net fluxes and performs calibration and other corrections, this program reads the ``abnet'' fluxes from the MELO or MEHI file and performs no other corrections. Thus, the fluxes may be slightly different than those returned by IUESPEC

To convert MELO or MEHI data to other formats, run IUESPEC and perform any desired corrections (see Chapter 5. You may then use IUESAVE to create a SAV file, or ASC_WRITE to create an ASCII file. To create a FITS file, you may wish to use KEYGEN to convert the H vector to a FITS file and then use IFITSWRT or VECFITS to create a FITS file.

next up previous contents
Next: 3.2 FITS Files Up: 3.1 RDAF-format Files Previous: 3.1.2 Converting RDAF Format