My brother has a Minolta XG-M with a generic auto winder. He took photos of ma's Christmas tree and those wound manually look fine, but those where he used the winder have white streaks, looks like some one smeared liquid white frosting, with a old paint brush, length wise across the negatives. The lines are wavy. I wondered why my brother called them wispy in the letter, but I agree with his term. The photo is pretty much correctly exposed except for this transparent white smear. I told him to toss the auto winder, but what causes this to happen?