https://en.wikipedia.org/wiki/Exposure_value
ev
exposure value
ISO
filmspeed
https://en.wikipedia.org/wiki/Film_speed
f-number
https://en.wikipedia.org/wiki/F-number#Working_f-number
mark
https://en.wikipedia.org/wiki/Exposure_value
ev
exposure value
ISO
filmspeed
https://en.wikipedia.org/wiki/Film_speed
f-number
https://en.wikipedia.org/wiki/F-number#Working_f-number
mark