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I realize that the Nikon CLS technology can be intimidating. When I started my herd of SB800s several years ago with an initial pair, I spent a couple days or so, full time, figuring out how it all worked. Everything you need to know is in the manual, it is just a bit difficult to figure out how to go through it all. Once the lights came on and I started photographing night shots of law enforcement officers in various tactical scenarios, the herd quickly grew to twelve SB800s, one SB900 (now used as the on-camera master), one SB600, four SB-R200s, and one SU-800. I understand your frustration.
With a single SB600, it is not clear what you want to do: use it as a single, on-camera unit; or somehow trigger it as a remote unit.
Some things to think about.
1) Your D100 camera is not compatible with the CLS technology, as it predates it. Ergo, your SB600 cannot be used as a CLS remote with the D100.
2) Your SB600 can be used as a single, on-camera unit, or as a remote when the camera is equipped with a master unit, which can be either a Nikon SB900, SB800, or the SU-800, which is a master without the flash head.
3) According to the SB600 manual, when mounted on the D100, it can be used in the D-TTL, BL, and Manual modes, which will get you started.
4) As I understand it, the Pocket Wizard TT5 system simply converts the infrared pulses from an on-camera master unit (see 2, above) to radio frequency for transmission to one or more remotes, and then converts them back to infrared. Without an on-camera master unit, you cannot use your SB600 as a remote. Some Nikonians claim to have success with various optical triggers on remote SB600s. I have tried several and the only one that works for me is the Nikon SU-4 module, which is quite expensive.
5) For any TTL flash work, some form of preflash signaling is required, either in full TTL, or Manual mode. As you know, in the TTL mode the CLS technology must measure the reflected light from the subject while the flash is firing and the shutter is open. In the manual mode, the on-camera master sends a power level signal to the remote units prior to shutter opening. This is simply how it works.
6) All of that said, your D70 Nikon can be used to control your SB600 in the remote mode. This is not complicated and once you see how it works you will be a fan of CLS.
7) My last half-day workshop here in Phoenix was last November or December. I usually conduct a couple a year, but do not have the next one scheduled yet. These are free workshops conducted in a local pro shop, and usually attended by 25 to 30 people.
8) If you are ever planning to be in the Phoenix area, send me an advance email message. Schedule permitting, I will be glad to get together with you for some one-on-one speedlight discussion and experience. For a single remote SB600 with your D70, an hour or so will have you up and running and comfortable with CLS, preflash and all. Time permimtting, I will set up several remote SB800s with one of my cameras and show you how the multiple remote groups work.
Finally, tell me a bit more about your plans for speedlight (flash) usage.
HBB in Phoenix, Arizona Nikonian Team Member
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