A friend shot Portra 160, 400, and 800, all with the camera ISO set to 100. The guy at the counter at Central Camera in Chicago says to develop normally because pull-process will change the colors. What should he do? BTW, this was a low-budget wedding that he shot for free for a friend.
He's pretty new with film and I thought he was nuts doing it, but I guess they can't complain about the price.
The 800 will be quite usable with standard processing, especially if it was used with mixed light sources (where the colour response is unpredictable anyways).
Hey, thank you all. Your info has been passed on and taken a lot of worry out off his mind. I figured the 100-160 difference was so small that it wouldn't even be noticed and have seen some shots, either here or on flickr, where people pushed the 400 by 2 stops and it looked alright. The 800 was a bit worrying.
Color neg has long been known for well tolerating overexposure, and less well tolerating underexposure (muddy shadows).... -1 to +3EV is the exposure range well tolerated by color neg materials! I would leave all the films alone and go with standard processing.