[daip] Versions compatibility

[Eric Greisen]

Antoine Bouchard writes:

 > Until recently, i was using the 15OCT94 version of AIPS. The new version
 > (31DEC99) was installed and i wonder if it is possible to directly copy
 > the old images into the new version without converting them in FITS files.
 > Is there a way to view the files without starting AIPS?

I am a bit uncertain since this is a very large jump in version.  I do
know the following: once an image or uv data set is accessed in
31DEC99 it cannot be accessed in your old version.  I believe that the
new versions do ther format conversions on the fly and mostly
transparently.  They will recommend that after a GET operation you
re-save the rebuilt area.  he header formats will change in a way that
gives the old versions a lot of trouble.  If any of the files are
critical, you should probably back them up on tape before starting
this just to be safe.

Eric