Eric Deutsch
Department of Astronomy, University of Washington

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Eric Deutsch's DIS Notes

DIS Stuff

• Please note that lots of this stuff is pretty old. I haven't had the chance to work with DIS data much at all recently.
• PostScript file containing the documentation to some IDL software which is useful for looking at raw DIS data (e.g. auto-(zerocor,flatcor,rotate,display) software).
• Examine the individual routines or download the libraries.
• tar file (18 MB!) which contains a set of sample images with a description of each of the images.
• PostScript file (1.2 MB) of a set of images (output of 'disboth' procedure) which shows the nature of the ghosting problem. Despite the comments in the DIS manual, ghosts are visible on both red and blue CCD without and WITH the g and r filters in place! The top row is the red CCD; the bottom row is the blue CCD. In order left to right: unfiltered images (north up east left); filtered images (north up east left); filtered images same field rotated 90 degrees) (north is now left). Note that ghosts appear in the north direction on unrotated images. Note that the orientations shown are NOT the way they come out of the camera.
• PostScript file (7 kB) of a plot of the shape of a low-resolution DIS spectral line (taken from an arc-lamp exposure by Eddie Bergeron). Clearly, the line is not very symmetrical, although the degree of asymmetry should not be too worrisome for most observing projects. Two possibilities for this spring to mind: 1) the general drooling of the chip (a charge transfer problem?); I think the sense of the drooling is the correct way, but I'm not sure; 2) an unsharp edge to the slit. If the slit is the problem, that could be tested by using an acetate slit or studying the problem in high-resolution, too.
• Text file of Spectrophotometric standards suitable for importation into Remark. Note that these are the 1 micron extension standards from Massey and Gronwall ApJ 358 pg. 344. By importing this into Remark, it is possible to choose these standards from a list and slew automatically without typing in the coordinates.
• Here are some sample DIS sky spectra:
  1200-second BLUE side moonless sky ( PostScript file or GIF file)
  1200-second RED side moonless sky ( PostScript file or GIF file)
  1200-second BLUE side gray time ( PostScript file or GIF file)
  1200-second RED side gray time ( PostScript file or GIF file)
  
• See the references list below for some papers about standard stars and night sky lines