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Here's another shot from my dad and grandparents' trip from Illinois back to LA through Zion. View full size.
We visited Zion in 1983 and that indeed was the color of the roads there, a beautiful red-brown. It contrasted nicely with the amber of the traffic markings.
The negatives are 6 X 6cm.
... that treacle was used in the seventies instead of asphalt! That's an incredibly rich deep brown road.
WOW! Lookit that sky. Not to mention the color of the rocks. Taking a wild stab at it, I'm guessing these Zion shots are from Kodacolor negatives on 126 film (image size about 28 x 28 mm).
EDIT: Ooops - you said it was a Brownie in the earlier shot, which means this was probably 127 film, with a 4 x 4 cm negative size.
Also: 1970 Chevrolet Impala convertible.
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