Bill's link to Alson van der Meulen's SB-800 measurements is the best we have to date concerning electronic details of the CLS technology. I worked with Alson several years ago when my SB800 herd was in its infancy. What is really needed is a four channel recording oscilloscope. NAS and other syndromes keep getting in my way.
There are a couple ways of extending the range of Nikon speedlights that may be of use to you.
1) Place all on-camera and remote units in the SU-4 mode. In this manner, one can daisy chain them somewhat farther than the Nikon specified range. I haven't tested this to see just how far I can go, but I have easily gone sixty feet and more. SU-4 of course places you in a strictly manual mode, with no TTL capability.
I have also fired remote SB800s in CLS TTL mode at sixty feet or so at night, with careful positioning of on-camera master/commander and remote units.
2) Current generation Pocket Wizards (Plus II and MultiMax units) are radio frequency (RF) and will extend the range to an advertised 1,600 feet. These products are also manual mode only, with no TTL capability. I recently acquired a half dozen of each of these units and am working out some complex, timed interval night shots with moving law enforcement vehicles.
Recently announced Pocket Wizard models claim to provide RF CLS TTL capability at similar ranges. The Canon models are supposed to ship in a few months and the Nikon versions later this year.
Thanks again for joining us. I hope you find your Nikonian experience rewarding.
HBB in Phoenix, Arizona Nikonian Team Member
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