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.