Paul C. Buff, Inc. Technical Forum

Hey guys, I've been doing some research on weather a b800 would be enough for the look I'm going for. (my buddy is selling his for a really good price but I want to make sure i'll have enough power)

Basically I will be shooting at the beach around noon when the sun is high and bright. I will be using a singh ray variable nd filter to underexpose the sky(-2 to-3 stops?) mounted on 17-40mm. 1 light set up with b800 w/ 22" old skool pcb white bd. triggered with pocket wizards.

Now, going by the pcb specs, the b800 should output f22 @ 5' with the deflector on the bd taken off. I want to shoot around f11 1/160th at iso 100. I don't have alot of room to play with as far as manipulating my ambient and flash because the ND filter will affect both of them.

My question is, has anyone done something similar with great results? I'm also considering the 11" long throw reflector to give me some room to play with. I might have to experiment with it's harsher light.

b1600 or einstein are out of the question for now as i have other things to buy first :(

As a starting point, on a sunny day, you are looking at f/16 at 1/125 @ISO100. 1/160s would be about f/11'7 (f/14). This would more or less properly expose the sky. To under expose the sky by 2-3 stops, you are now looking at f22'7 to f32'7. This means you would need to have a modifier/light/distance combo that can produce f/22'7 to f/32'7 to get your ratio. Once you add the ND filter, the flash and ambient will go down in ratio.

You will need that same ratio regardless of how much ND filtration you use. However, If you can increase your shutter speed (and still not exceed your x-sync speed), that will require less flash power to achieve the same goal.

One last thought is to place the area that would normally band in studio in a place that would not be noticed. Here is a link that would help explain that: http://strobist.blogspot.com/2008/10/gr ... -sync.html