>>4228257You don't need to use an r72, a red 25 is perfectly fine and much easier to deal with. Rate the film at 400 if metering through the filter. If using a handheld meter, set your iso to 50 (to factor for the red filter). Only shoot in sunny conditions.
>>4228297Rangeclouse can hook you up with a roll or two of provia 400 if you don't mind a slight magenta shift.
