film background realy light - looks like underdeveloped

[rmkuzma]

I have Agfa Proset 9550. I image form a pc and mac. The pc stuff comes out fine, meaning the background where there is no images is black, but on the mac side when I image the background where there is no images comes out very light. Making the film look like it is underdevelopes.

Does anyone out there have any idea what is goin on or how to fix it.

Thanks,
Rich