Hi Don,
I live in the desert of California and I used to
own a one hour photo lab. In the lab I would regularly get film that was
left in a car during the heat of the day. This film was badly damaged by
the heat and almost impossible to print. Based on this, my personal
opinion is to hyper B&W at 50 and color at 30 degrees C. Exposing
color film to 122 degrees F is the same as leaving it in the hot
car.
Also being from So Calif., for more years
than I want to remember, the heat build up in a closed car is not just
limited to 122 degrees, more like 180 in a rear parcel shelf. It gets
hot enuf to kill children in a very short time. Need
proof, talk to any paramedic that has been involved in the death of
children who were locked in closed car.
As one who has hypered at 50C for many
years I have yet to see film degradation of any sort, but then again I
may just have been lucky for all these years ;-))))>