ASCII Table tricks

[RANDY THOMPSON 286-8800 (301)]

  I agree with Bill Pence and Barry Schlesinger in interpreting the 
current NOST standard as saying only ASCII text characters (i.e hexidecimal
20-7E) should appear in the records of an ASCII Tables extension. However,
it seems to me that a Binary Tables extension could be used to store the 
data described earlier by Steve Allen? Maybe I'm missing something (since I 
haven't seen this suggested already), but why not store the ASCII text as 
character strings and define fields of byte data type to contain the byte 
values of non-printable ASCII characters? If you strip off the headers, 
the remaining records should be identical to those that could be produced 
with the ASCII Tables extension.
   If this isn't suitable, I would think one could still propose a change to 
the current FITS standard that would (unambiguously) allow non-printable ASCII 
characters as non-field values. If existing FITS readers are really not 
impacted, why should such a proposed change not be approved? Of course, the
change would still need to go through the established approval process.
   Alternatively, one could define a new table extension following the 
requirements for conforming extensions. The new extension could simply follow 
the existing rules for ASCII Tables but without the ASCII text restrictions.  

Randy Thompson