* first post *
Hoping someone can please check my maths on this.
I'm new to guide numbers but not new to photography. But my only experience using my SB700 is about 4 years ago, I did some kitchen tabletop splashtography with my Camera Axe.
So, now I'm hoping to do something a bit more outdoorsy and photograph a waterfall and gorge near my house at night.
The subject distance is about 150 meters, and I'll be using F8.
So, (if I understand this correctly) GN = 150 x 8
or 1200m @ ISO 100.
Is this correct? Is there a flash available that has a GN this high?