question on data padding

[Thomas Dame]

According to the FITS standard, the data array must be 
an integer multiple of 2880 bytes in length.  To achieve
this, Wells et al. (1981) states that:

     "The remainder of the last data array record after 
    the last pixel of the array will be padded with zeros."

When the data is stored as 16-bit integers (BITPIX=16), it
is not clear to me whether the padding should be:

a) integer zero (all bits zero)

b) the integer representing zero intensity in the image 
  (i.e., the integer I such that BZERO + I*BSCALE = 0).

c) the integer BLANK 


I would guess Wells et al. mean case (a), but case (c) would
seem like a better alternative, since integer zero can represent
a perfectly reasonable intensity in the image.  Admittedly this
is a minor issue that should hardly ever matter, but I would
like to follow the FITS standard.

Many thanks,

Tom Dame
tdame at cfa.harvard.edu