Archived posting to the Leica Users Group, 1999/02/17
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]>EV is strictly a function of shutter speed and aperture. Just look at any >Hasselblad C or CF lens to convince yourself. Specifying exposure requires >both EV and film speed. > >Dan C. > >>> The EV is a function >>>of light AND film speed. >> Are we talking at cross-purposes here? I understood Mark's original statement to mean that the required EV was dependent on the intensity of light and the sensitivity of the film - that is true, surely. However, EV itself is solely a function of speed and aperture and is independent of film speed and the amount of light. These are not contradictory statements. Any apparent contradiction is the fault of my inability to explain myself! I remember when I first used my father's Balda. You set the film speed on the Gossen lightmeter and read off the EV (EV determined by film speed and light). Then you set that EV on the lens and locked the shutter/aperture relationship (EV being a description of shutter speed and aperture relationship). Then you twisted both rings round to the combination you required. Regards, Malcolm