What this rule states is that on bright sunny day if you set the shutter speed to the reciprocal of the ISO and the fstop to 16 then you get a good exposure.
So as a worked example:
ISO 100, 1/100, f/16 = correct exposure on a sunny day.
Since Mavic can't go to f/16 and you want a slower shutter speed you need the ND filter.
So the full stop fstops are:
f/1.4, f/2, f/2.8, f/4, f/5.6, f/8, f/11, f/16, f/22 and f/32
ND4= 2 stops
ND8 = 3 stops
ND16 = 4 stops. and so on.
So if you wanted to shoot as ISO 100, 1/60 you need to go down at least 2 stop.
One for the f/11 and one for the 1/60 (which is about double 1/100)
And of course on an overcast day you would need a smaller fstop.
I leave the rest to you. Pick your poison but you really only need one.
If you prefer a larger aperture then get a stronger one.
With all the sophistication of modern metering system, it seems like the good ol’ Sunny 16 Rule can be dismissed as one of the old relics of the film era. But it is still a valid and useful rule nonetheless, and one that can teach growing photographers about the principles of metering. So if you...
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