Re: [TASS] RA and Dec in MkIV files

[Tom Droege <droege@WWA.COM>]

Ted and all,

Just two cents worth from a non-programmer.  My bet is that the best thing
to do is to first fit the frame to the star catalog.  Then get accurate
positions from the star catalog fit to find the exact limits of the frame.
Then correct the star positions.  Or some such.  In other words, don't
count on the location from the FITS header even to compute where you are in
transformation space.  But as I say, what do I know about such stuff.

Tom Droege

At 03:15 PM 12/17/99 -0800, you wrote:
>Chris and all,
>This is a couple of questions for Chris, but I'll post them here as
>others may be interested.  I'm working on modifying the MkIVStar
>program to handle the pixel to RA/Dec conversion for the Mk IV.
>Chris, I believe you're writing the program that will produce the FITS
>files that will be the main input to MkIVStar.  What point in the
>image will the RA and Dec in the FITS header refer to? (e.g. center of
>image, top left-hand corner or where?)  And how accurate do you expect
>the RA and Dec to be?
>Thanks,
>
>
>                                Ted
>
>