Paul C. Buff, Inc. Technical Forum

I expect this question has been covered before, but I have yet to find a simple, clear statement that addresses my needs.

Here is what I have:
2x X1600s, 1x X800 White Lightnings
Nikon D3

Here is what I want to do: normal studio portraits and studio dance photography. The latter will require shutter speeds greater than my camera's ordinary sync speed.

I am looking to purchase Pocket Wizard equipment to control my lights. So I will buy a MiniTT1 as my transmitter and then some number of FlexTT5s.

Here is my first problem. Will one FlexTT5 be sufficient? I would think so because the flash it triggers would fire the other units, but "different people say different things".

My next question relates to the AC9 Alien Bees adapter from Pocket Wizard. Do I need one of these? If so, do I need one for each FlexTT5 that I purchase?

Finally, are there any other gizmos, connectors, etc. that I will need to make my White Lightnings work with Pocket Wizard equipment?

Thanks in advance,
Alec Himwich

For the clearest answers on "hypersync", or allowing the camera to shoot faster than x-sync, as far as hardware goes, your best bet would be to contact Pocket Wizard, they design it, test it, make it, and describe what it does. Even with the MC2, most PW tech stuff need to go to thier tech support.

However, at what shutter speeds are you planning on using, or do you need? With HyperSync, faster shutter speeds are going to cut into the effective output, similar to lowering flash output, and possibly lead to uneven exposure.

Your X1600 flashes have a t.1 time of 1/2000 of a second in 1/4 power mode (via the switch, not the slider). Your X800 are 1/1100, t.1 time at full power. This would translate to stopping power of very similar shutter speeds.

In low light, there is not enough ambient light to create its own blur at standard x-sync speeds.

Thank you for your speedy response.

I am thinking that I will do be OK with shutter speeds of 1/1000 sec.

If that is so it sounds as if I will be fine in any case.

What does t.1 time represent?

t.1 represents the time the flash output is above 10% peak intensity. There is a measurable time that flashes emit light (which varies, of course, from flash to flash and power setting to power setting). Peak intensity is virtually instantaneous, with a tail that tapers off. Most flash units are measured by how long it takes to reach 50% intensity (t.5), however, there is still considerable amount of light that follows that point that can easily lead to blur (t.5 is only 1 stop below peak). t.1 is about 2.3 stops below peak, and about 3 times longer than t.5, and a light level low enough that it will not typically contribute enough light to introduce blur.

As always, test this method (or any method or equipment) to ensure it will do what you intend to do enough in advance that you can make alterations if needed.

T.125 is 3f down from full illumination. T.1 is -3.3f, not 2.3f.

Sorry, you are correct. I found the error in my math.

With tongue in cheek, TS has to agree with me because he works for me. But I have to say he does a darn good job here and seldom makes mistakes. GO TS.