Paul C. Buff, Inc. Technical Forum

At a recent on-location shoot, I used two Einstein units, triggered by CSXCVs receiving signals from a camera-mounted CST. The Einstein used as the main light was about 30 feet away from and about 13 feet above the CST, with a clear line-of-sight to the CST. The Einstein used as fill was about 2 feet behind and 3 feet above the camera/CST. Both Einsteins were powered by VMLs, and were firing into 86-inch PLMs.

During the shoot, in about 4 shots out of 100, the main Einstein failed to fire, while the fill Einstein did fire. The problem shots all happened within a couple of minutes of each other. After these few problems shots, both the main and fill Einsteins worked without problem for the rest of the shoot.

Can anyone suggest the most likely cause(s) for this behavior?

It could be the main was fired too fast, and the fill was powered low enough to recycle faster. Or, there could have been a strange interference. It could have been a relocation of the main-to-camera relationship, even a minor one. It could have been a cold battery warming up (which could increase voltage), and therefore increasing the range from marginal to good.

Without knowing more specifics, it would be impossible to speculate. Even with knowing more, it would be hard to speculate. 30 feet in open line of sight conditions is well within the operating range of CyberSync. However, open water, metal buildings, wire structures, etc. can all impact range, sometimes dramatically.