strange white line around direct positive paper

i just bought another box of imago direct positive which is apparently the same as the ilford stuff just coated on a plastic paper

whilst dialing in the pre flash time i noticed that there was a neat white line all the way around each sheet

can anybody explain this
this test was way under exposed as far as the step wedge was concerned which is why it came out black
the paper was not in a holder i just put it on the base of my enlarger and stepped a piece of card over it
as normal
the extra white at the top right is where it did not go into the dev as my clip was there
and the grayness is because i pulled it as soon as i saw there was no step wedge on it

any ideas ?

best robin

It is edge fog from a light leak.
Had the package been opened?

Hi Matt

the package had not been opened
it might be edge fog but it is perfectly even all the way around with a really sharp edge
I wondered if they were cutting the stuff with a laser or something ?

robin

MattKing said:

It is edge fog from a light leak.
Had the package been opened?

Click to expand...

I almost wrote the same thing but it looks pretty even, and the stack of paper would have needed to be exposed fairly evenly from all sides. If it comes in a black plastic bag like other photopaper, it's hard to imagine how that could happen...