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refspec

tomph wrote on Mar 24, 2008

heya
I have created a single refence spectrum from a rubidium lamp and am trying to use refspec using this spectrum and a raw image spectrum of betelgeuse.

I have seen that the sort and group parameters needed to be set to none and have done so accordingly. however when i try to execute refspec the following happens:

ERROR: No reference images specified

the parameters for refspec are as follows:

refspectra.input = "betelgeuse.fits"
refspectra.answer =
refspectra.references = "lamp_four_ap.fits"
refspectra.apertures = ""
refspectra.refaps = ""
refspectra.ignoreaps = yes
refspectra.select = "interp"
refspectra.sort = "none"
refspectra.group = "none"
refspectra.time = no
refspectra.timewrap = 17.
refspectra.override = no
refspectra.confirm = yes
refspectra.assign = yes
refspectra.logfiles = "STDOUT,logfile"
refspectra.verbose = no
refspectra.mode = "ql"
# EOF

i think it may be because my reference image is a .fits file and needs to be .imh or something. The reason i would have got a .fits reference from earlier work using apall and identify was because i was told to use
set imtype=fits
so perhaps i should start again and omit this line if the reference type is the problem.

Thanks everyone

Tom

tomph wrote on Mar 24, 2008

If it helps i get the same error message

ERROR: No reference images specified

when using a different reference lamp without image type set to .fits (giving me .imh files)

i.e.
PACKAGE = onedspec
TASK = refspectra

input = capella.fits List of input spectra
(referen= lamp_one_ap.imh) List of reference spectra
(apertur= ) Input aperture selection list
(refaps = ) Reference aperture selection list
(ignorea= yes) Ignore input and reference apertures?
(select = interp) Selection method for reference spectra
(sort = none) Sort key
(group = none) Group key
(time = no) Is sort key a time?
(timewra= 17.) Time wrap point for time sorting
(overrid= no) Override previous assignments?
(confirm= yes) Confirm reference spectrum assignments?
(assign = yes) Assign the reference spectra to the input spectr
(logfile= STDOUT,logfile) List of logfiles
(verbose= no) Verbose log output?
answer = Accept assignment?
(mode = ql)

i dont really have any more ideas as to why it doesnt think i have a reference image...

Help!

Francisco Valdes wrote on Mar 24, 2008

Hi,

This is not a very well documented definition of a reference spectrum. It is defined in the second paragraph of the REFSPEC help page:


A reference spectrum is defined to be a spectrum that has been used
to calculate a wavelength solution with the tasks IDENTIFY or
REIDENTIFY. These tasks have set the keyword REFSPEC1 in the image
header equal to the spectrum's own name.


So in your case you either have to have run IDENTIFY or equivalent task on lamp_four_ap.fits or you have to set the REFSPEC1 keyword with HEDIT. Note that you can skip REFSPEC if you want to explicitly assign dispersion solutions to images. REFSPEC is intendend when you have many arc calibrations interspersed in many object spectra and you want an automatic way to assign the arcs to the objects, usually by proximity in time.

Yours,
Frank Valdes

tomph wrote on Mar 24, 2008

Brilliant, thanks a lot I now have calibrated extracted spectra!

Thanks ever so much

Tom

Last post on Mar 24, 2008