The Visual Target Tuner (VTT)
As an aid to HST observers, a display tool was developed by a collaborating team from NASA Goddard Space Flight Center (GSFC) and the Space Telescope Science Institute (STScI). This tool displays HST instrument apertures superimposed on FITS format sky images; Digitized Sky Survey (DSS) images, NASA/IPAC Extragalactic Database (NED) images, or other suitable FITS images. The tool can be used to display primary and parallel apertures, rotate apertures, centroid objects, and display catalog overlays. For a more detailed discussion of the VTT, see the "Phase I Proposal Instructions" or go to the VTT web page at:
http://apt.stsci.edu/vtt/
Figure 3.1: Specifying a NICMOS Observation
