Syntax: arc2obj (Arclamp FITS file) (Object FITS file) [bracket=(2nd arclamp FITS file)] [arcmode=] [-var] [-novac] [-nohc] [-atm] [-sky] [-isky] [-sum] [skyshift=n] [ps=] Copy wavelength scale from an arclamp to an object. Convert from air/observed to vacuum/heliocentric wavelengths and correct for atmospheric extinction. bracket= : Average the wavelength scales in the first arclamp file with this second arclamp file. (for arclamp exposures which bracket object exposure.) arcmode= : Arclamp wavelength scale averaging mode: 0 : Average scales of 1st and 2nd arclamps. (default) 1 : Shift scale to 1st arclamp. 2 : Shift scale to 2nd arclamp. -var : Attempt to read Var-###.fits file, apply same corrections as to Flux-###.fits and convert to error array as Err-###.fits. -sky : Shift to skylines. Use: Flux-### and Sky-###. (and put wavelength scale on Sky-### file.) -isky : Interactive "-sky" (start pgdisp window first). -sum : Apply Flux-### corrections to Sum-### file. -atm : Apply atmospheric extinction correction. -novac : No vacuum correction. -nohc : No heliocentric correction. skyshift=n : Apply sky shift of n pixels. ps= : PostScript skyshift plot file ("none"=no plot.)