Well I can't enlarge the negative enough to see - however I did rescan using Vuescan - lower resolution than the non-ICE HP sofware and the effect seems to have gone - so I guess it must be the software - which has no setting for B&W negative - only colour (unlike Vuescan). Thanks for suggesting that! Looks like I'll be buying a copy to activate my Vuescan trail!

Seeing as I'm paranoid however - I am right about the neg being too low in contrast?