Sparrow
Veteran
... you could always worry about radon gas!! that accounts for more than 50% of the background radiation we get at ground level ...
135format
Established
that would be a new one which came out before the 7 which came out before the 7II which is how long ago...
sevo
Fokutorendaburando
That is positively an ink issue, again.
waileong
Well-known
Two ink issues to hit two major manufacturers? In fact, if you search there's also another example involving kodak colour film....
sevo
Fokutorendaburando
It is perfectly common for heavily expired or overheated film to expose such a behaviour - indeed it is hard to avoid. Inks are made up of oils and high surface pigments, and once migration phenomena begin to occur, even a chemically inert printed patch will attract hydrophobic substances and complex molecules more than the surrounding bare paper, due to its surface properties.
As I said, it is practically impossible for any external source to expose a roll of film evenly from all sides and from the outer layer right to the centre of the spool - so we can categorically exclude x-rays or cosmic radiation. If any, there could be a light leak in the production or lab, occurring at a time when the film is not on its roll - but it is very hard to imagine a situation where something would manage to selectively expose the film right through the backing paper without entirely zapping its exposed front.
Oh, and wasn't the Rollei 120 spooled at Ilford? I remember something like that from a discussion on its barely legible numbers - a misfeature it shares with Ilford films...