Shooting in sunny daylight

Sunny 16 rule….

Open aperture at f16… shutterspeed is 1/iso that is set.

So lowest iso is 100… so shutterspeed = 1/100

If need to blur background…. Say aperture opening up to f4…

Meaning from f16 to f4…. Is difference of 4 stops…

So to maintain exposure… shutterspeed must be 4 stops faster…

1/100à1/200à1/400à1/800à1/1600

So to use f4, iso 100.. shutterspeed is 1/1600

this is a good place to start .. adjust from there...