The silence is deafening. . .

Alright all. I suppose I was asking the right question(s) in the
wrong manner in the beginning. I have now actually figured out how to
interpret 2-D image data. The information literally has to be read in
8-byte increments and converted to a double. That will then allow me
to map RGB pixel data to a buffer.

*THAT* is what I needed to know. How to read in and interpret the
data. I had *NO* idea what that "garbage" was supposed to mean or how
many chickens I needed to sacrifice in order to get it to work.

Anyway, thanks to all that contributed. My apologies for any
confusion.

Regards,
Michael

On Aug 27, 10:38 am, Michael Williams wrote:
Ok, I actually asked a follow-on question in another post/e-mail.
Basically I asked if these astronomers images were literally live
images (perhaps of the stars, or nieces and nephews), or if they were
simply arbitrary graphical representations of data that had no
reference in reality. Also, given the fact that, as you said,
reverse transformation isn't always possible, why in the world does
it matter if the user can perform image manipulations of any type? I
mean, if there is no consistent way to produce an image, then why do
we care?

Thanks,
Michael

On Aug 27, 2007, at 5:15 AM, Thierry Forveille wrote:

gberz3 a écrit :
Why would *anyone* present FITS data as images if they are
not image data? Why not represent it as sound?
I guess that's what I'm getting at. What relevance does an image
have
to actual FITS data if there is no "attached" image, and what is the
proper means by which to display said image?
The issue is mostly your notion of an image, vs an astronomer's
notion of the same. To you an image is something that can be
univocally displayed on a screen or printed, while to
astronomers it is a set of values (ideally in physical units,
such as Watts per square meter per steradian) sampled on a
regular grid. There is some link between the two notions,
but not a unique one: an astronomer's image can be displayed
but not in one unique way, and the reverse transformation
if/when at all possible, requires additional information
(e.g. the physical values for a subset of the pixels) and
significant calibration work. Essentially, an astromer's
image is a richer dataset, and someone needs to decide how
to degrade that information to what a display can show.

In addition, images (in the astronomer's definition) is only
one of the data classes that can be stored in FITS.