Paul C. Buff, Inc. Technical Forum

Hi all,

I usually position my strobes (3 Einsteins), and then power on and meter them with my CC in hand. At that point I use a CST on the hot shoe of my camera (5D mkIII) to fire them. Each time I go to the camera and shoot the first test shot, the CST fails to trigger the strobes. I then play with the test button or wiggle it in the hot shoe before it actually triggers. At yesterday's shoot it didn't even trigger from the test button at first.

Once I get it to trigger the first time, it's rock solid. Am I doing something wrong? Is there a possible conflict between the CST and the Cyber Commander and the 3CSXCVs? Is my specific CST possibly faulty? I love all my PCB gear, but it looks bad when you have an entire sports team staring at you as you try to handle tech issues.

Thanks for any advice!

Have you noted if the LED on the transmitter blinks when the lights fail to fire? The LED on the transmitter tells you that the CST is transmitting a signal. If this does not light up from the shutter button or its own test button, then there is either no power (bad battery, no battery, misinstalled battery, bad battery contact, or a fault in the CST) or there is no contact being made between the camera and CST.

Is the CST also connected by the sync cord while installed in the hotshoe (it should not be)?

Is the camera in live view?

I did happen to notice at yesterday's shoot, that the red led did not blink when I hit the test button the first few times. At that point I removed it from the camera and reseated it on the hotshoe. After a shot or two it transmitted and was consistent the rest of the evening.

You know, now that I think about it, the day it arrived I put it on my camera and it failed to trigger. I rotated the freq knob to each setting until it triggered, which was freq 1, which is exactly where I had started. I assumed that it was just user error as it fired consistently the rest of that day. It's always an issue at the start of a shoot.

It has a battery and it is installed with the + pole down. I don't use any sync cables. I just added a B800 to my kit, but trigger that via the optical slave. I'm not using live view. My camera is new and fires speedlites via radio triggers without a prob. IDK, a bad contact maybe?

Thanks again.