The exposure value,EV, of a photograph can be calculated from the time, t, in seconds that the shutter was open and the value of the f-stop,f, the picture was taken at using by using the logarithmic equation:
EV=logbase2(f^2/t)
a. use the properties of logarithms to expand the formula for EV:
b. Keith takes a picture of a waterfall with a shutter speed of 1/60 second at f/5.657. he likes the exposure of his picture, but want to leave the shutter open four times as long to better capture the motion of the water. What f-stop should he use on his next picture.
Please help!
