Therion appears to correct for mag deviation automatically, based on the date that a survey was carried out. is it possible to turn this feature off within specific surveys? I have much legacy data where either the relevant correction has already been applied or where they have recorded a "compass correction" which includes both instrument error and mag deviation in one figure.
Graham -- graham.mullan at coly.org.uk 0117 9502556 or 07887 637064 (or 0844 2327803)
