----- Original Message ----- From: James Sent: Wednesday, October 18, 2006 7:37 PM Subject: Remedial film photography. :)
> Can someone please explain to me the reason that people load 50 iso > film and shoot > it with the camera set at 12 iso (numbers just for example). My fave is still PanF at ISO 12 or so. Colour neg film often seems to benefit from some overexposure from the box speed. I always found B&W film (real B&W, not that chromogenic stuff) speed to be much slower, sometimes several stops slower, than the box speed. > > What are the benefits of doing this? It doesn't change the speed of > the film...just > the speed the camera's meter thinks the film is. I assume it is so > you can > selectively over or under expose a bit, but can't you just do that > with your > exposure setting? The ISO of a film is determined by a particular standardized method, but film speed is a personal thing, since your meter may not match the calibration standard, your meter may not be colourblind (I don't think this is such a big deal now, but watch it with older meters), and you might just like more shadow detail than the box speed allows. > > As you can tell, I don't understand why people over or under rate the > iso of their > film deliberately. Read up on the Zone System. It was one of St. Ansel's teachings, and I think his book "The Negative" is a good place to start. William Robb -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net
