Space Telescope Format

The Space Telescope Format (STF) is used for storing Hubble Space Telescope (HST) data. It was introduced for the STSDAS package (see Section ), but is now understood by most IRAF tasks. Like the OIF format, an STF dataset comprises two files: one is the header file, and has the extension .xxh, where x can be any alphanumeric character, while the other contains the actual data values and has a .xxd suffix. The most usual file extensions are .hhh for header files and .hhd for data files. These files are usually kept together in the same directory. STSDAS files have the advantage that the header file is an ASCII file and can be read on a terminal without using IRAF at all (which is not true of .imh files; see above).