> 2^EV = A^2/T = LS/K > > As another point of reference, EV 0 is 1 second > @ f/1.0. > > When used to indicate a light level, EV usually assumes ISO 100. When you > determine camera settings, however, you need to adjust for ISO. With a > lighting level of "EV 10 with ISO 100," you'd use settings of EV 10 (1/125 > @ f/2.8) with an ISO 100 imager, but settings of EV 12 (1/500 @ f/2.8) with > an ISO 400 imager. So in this sense, the change in EV is linear with ISO speed.
This statement sounds contradictory to the equation introduced earlier (remember that you said manufacturers assume ISO 100. Exposure values increase by one when the exposure (controlled through time and/or aperture) doubles. This would indicate that EV 12 is 4 times as bright as EV 10, changing the exposure from 1/125 f/2.8 to 1/500 f/2.8 AT ISO 100. Regards, Lars -- .~. Lars Michael /V\ [EMAIL PROTECTED] /(_)\ http://www.larsmichael.com/ ^^ ^^ * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
