iraf.net

Hi,
I'm running doslit and I'm getting the following error:
Assign arc spectra for [imgname]
No arc reference assigned for [imgname]

It's also not creating the "idobj1arc1.ms" files

What is going wrong?

PACKAGE = kpnoslit
TASK = doslit

objects = @targcorlist List of object spectra
(arcs = @arclist) List of arc spectra
(arctabl= HgNeXe) Arc assignment table (optional)
(standar= ) List of standard star spectra

(readnoi= 2.7) Read out noise sigma (photons)
(gain = 1.29) Photon gain (photons/data number)
(datamax= 60000.) Max data value / cosmic ray threshold
(width = 5.) Width of profiles (pixels)
(crval = 1049) Approximate wavelength
(cdelt = 1) Approximate dispersion

(dispcor= yes) Dispersion correct spectra?
(extcor = yes) Extinction correct spectra?
(fluxcal= no) Flux calibrate spectra?
(resize = yes) Automatically resize apertures?
(clean = yes) Detect and replace bad pixels?
(splot = yes) Plot the final spectrum?
(redo = no) Redo operations if previously done?
(update = yes) Update spectra if cal data changes?
(quicklo= no) Minimally interactive quick-look?
(batch = no) Extract objects in batch?
(listonl= no) List steps but don't process?

(sparams= ) Algorithm parameters
(mode = ql)

I think I have an explanation as to why the arc fitting is failing. My arcs are not straight lines but curved. Is there a fitting routine that I can use to fit the arcs in 2D?
Thanks