INDISK/FITS test.fits
CREATE/IMAG ref_imagealog 1,npix lowlim,step NODATA
COMPUTE/IMAGE toto0001 = toto0001/median
COPY/IT toto0001.bdf test  :wave
CONVER/TABL  img = test #1 #2 ref_imagealog spline
EXTRAC/IMAG imgcut = img [lowcut:upcut]
OUTDIS/FITS imgcut name_spline.fits