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Downloading data



I have just downloaded some data for yet another
attempt at my Ensemble photometry ...

I find some changes have crept in.

Although the header (and help file) still says 13 columns,
I am getting 9. The two colour IDs and the two quality codes
have disappeared. Ah well - just a few minor changes to
my code.

One degree boxes now mean Sec(Declination) degrees in
RA so my boxes now overlap except on the equator. Just
another minor change to my code to ignore the stuff I have
read twice.

But some things have not changed. One is still given the
incorrect error estimates:

On Thu, 3 Mar 2005 17:27:30 -0500, Stupendous Man
<richmond@stupendous.cis.rit.edu> wrote:

> ...
>  Hmmm.  Before this week, I would have told someone to ignore
>the uncertainty values for _most_ purposes.  Now, I would tell
>someone to ignore them for _all_ purposes.

>  Fixes?
>
>     - I can imagine several ways to propagate the information
>           about actual sky levels into the calculation of
>           uncertainty in instrumental magnitude.  It would
>           mean modifying the TCL scripting code which runs
>           the pipeline and _possibly_ the C code of the
>           "phot" program within the XVista package.
>
>     - we can make available to users of the database some
>           better measure of the actual uncertainty in each
>           measurement.  There are several possibilities:

etc. etc.

But no - that would involve somebody other than me putting
in a few minor changes in their code.

Am I the only one who cares that this trivial problem
with uncertainty estimates continues to make the 
MK IV database a lot less useful than it could be?

Andrew Bennett, Avondale Vineyard, NS, Canada