Dear colleagues:
I am Montse Villar-Martin, at the Inst. de Astrofisica de Andalucia in
Spain.
I want to use dipso with SDSS spectra, but I am having difficulties to
read the
wavelength information.
Using 'sp0rd' or 'read' , the dispersion axis takes values in some weird
units that,
I seem to understand, have to do with the coefficientes in the header
that describe
the wavelength-pixel transformation.
I have tried to modify the image header information (CD1_1, CRVAL1, CDELT1)
and it works in the sense that now dipso 'reads amgstrongs'. However,
the problem
with this is that the pixel scale in amgstrongs is assumed to be
constant, which is
not the case for the original spectrum, so that the wavelength range is
wrong.
I have tried different thigns (such as dumping the spectrum into a
table), but I
find the same problems.
How can I get dipso to read the spectral information properely from SDSS
spectra?
Thanks a lot for your help, I don't know what else to try
Montse Villar-Martin
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