In a message dated 7/23/2002 12:28:43 PM Pacific Daylight Time, [EMAIL PROTECTED] writes:
> It's been mentioned before that 100 ISO film pushed 1 stop should be shot > at 320 ISO and that shooting it at 200 ISO is not a 1 stop push. How valid > > is this? A doubling of film speed is a one stop push. Rating ISO 100 film at ISO 200 is a one stop push, at ISO 400 it's a two stop push. This is the way I've always understood it. I found this, however, on the Kodak web site: "With longer development times, such as those used in push processing, EI values actually do increase, but only slightly. Underexpose a film by two stops and give it a two-stop push, and the real film speed will typically increase by perhaps a half stop. This means that the film is really underexposed by only 1 ½ stops, not two stops. But it is underexposed. " So, rating ISO 100 speed film at ISO 400 is only a 1 1/2 stop under exposure. Hummm.... -Brendan MacRae - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
