Ben Goren wrote:
spotread -a -v already shows ambient light levels in lux. Would it be possible to also show light levels in EV units? The conversion (for ISO 100) is: EV = log2(lux / 2.5) lux = 2.5 * 2**EV
As I understand it, EV (Exposure value) represents a camera shutter speed and aperture combination. For a given film speed (ISO), desired exposure (K factor) and light level there will be a resulting suggested EV, but EV itself is not a measure of the light level. So I don't think this belongs in spotread. It seems pretty trivial to set up a calculation (ie. by hand or with a spreadsheet) that would convert lux to EV given the ISO and the desired exposure. (Of course you also have to take into account whether you are measuring light reflected from the subject, or illumination levels.) Graeme Gill.