[daip] coordinates in AIPS

[Anna Bartkiewicz]

Dear Eric,
  Thank you very much for your explanations.
Is that possible, you could send me the 
formula of CD1_1, CD1_2, CD2_1, CD2_2 or where I could find it?
Is that possible that I could fix 
the rotation as 0 (CD1_2 and CD2_1=0???)
and leave CD1_1 and CD2_2 as 0.0219"?

Greetings,

Anna


> Note that the coordinate info you give is quite complicated: CD1_1 and CD2_2 
> are not equal 0.021922 and 0.021795 arcsec.  Furthermore CD1_2 and CD2_1 are 
> both positive meaning that a rotation interpretation is impossible.  The skew 
> and "rotation" are small but still affect a difference for 6 or more pixels 
> at the edges of your image.
>
> I fear that AIPS is not equipped to help you - what you need is a program 
> that understands the CD parameters in a general sense and regrids the image 
> onto an unskewed grid.  Some of the general FITS viewers can handle this 
> issue although I do not know if they have the regridding software.
>
> Eric Greisen
>