[fitsbits] EXPOSURE or OBSTIME?

[Eric Greisen]

Tom Kuiper writes:
 > I'm working on a radio spectral line data acquisition package and need to
 > decide
 > what keyword to use for integration time. An example FITS file that I have from
 > the SEST telescope at La Silla uses OBSTIME. The OGIP Spectral File Format
 > specifies EXPOSURE.  Are there any other keywords in use for this parameter?
 > Is there any hint of a convergence on a standard?
 > 

   Perhaps this is a case for me to recommend the use of a 1-pixel
axis to specify time, with the axis increment being the integration
time. 

   The VLBA uses INTTIM as a random parameter in a groups UV data set
and would use the same as a keyword or column label in a UV data
table.


    Eric Greisen