Odd flash problem, Cactus V2s.

Greetings again

I bet you guys are so sick of reading my posts, but I promise this will be the last one for a while if this problem can be solved.

Heres the setup picture before I do any explaining.

e r y k wrote in post #4833855
Greetings again

I bet you guys are so sick of reading my posts, but I promise this will be the last one for a while if this problem can be solved.

Heres the setup picture before I do any explaining.

(1. 580ex 2. 430ex 3.vivitar 285)

Since I just recently acquired my new flashes to use for my automotive photography, I figured there would be no better way to learn than to try it on my car.

To cut to the chase, when I was actually shooting images of the car from the other side of the image I just posted, the flashes triggered 100% of the time. I had zero problems. However, when I went to the other side to snap a picture of the setup, flash number 2 would refuse to fire. Maybe once out of every 10 tries. I thought maybe the batteries in the receiver would be bad, so I swapped the locations of the 430ex and the 285HV.

Oddly enough, the 285HV would now not fire. So that eliminates the bad receiver problem. Which makes me stumped. When I pressed the test fire button, all three flashes triggered fine, but when I switched to taking pictures, whatever flash was in position two would not fire.

It just doesn't make sense to me... why would this happen? The line of sight from the transmitter to receiver is most direct with flash number two, yet it is not triggering.

Any ideas? (yes you pacace, curtis, and flash zebra :P save me!)

People have reported problems triggering in close range (less than 1-2 metres) so maybe this is the problem here?

Potisdad wrote in post #4833868
People have reported problems triggering in close range (less than 1-2 metres) so maybe this is the problem here?

What I was going to suggest, too. Move a little farther away and see if #2 works.

that wouldnt make sense though? since flash number 3 is much closer than two?

plus when i was shooting from the other side, the flash triggered every time

e r y k wrote in post #4836763
that wouldnt make sense though? since flash number 3 is much closer than two?

plus when i was shooting from the other side, the flash triggered every time

Oh, OK. we must have misread your previous post because I thought you said that the #2 flash was the closest to you.

I'm starting to think there is a real problem with using the 430EXs with these units. I've just got them... and have not been able to get reliable results with the 430EX yet. I think the receivers mess with each other or the 430EX some how.

I've also wanted to try covering up the IR receiver on the front of the 430EX. And have wondered if the contacts (other than the center one) on the bottom of the 430EX are isolated enough from the metal part of the receiver.

I've done the antenna mod... and it has not made things better.

There is a mod to better isolate the inside of the receiver from other signals (noise). Looked like it involved putting something between the internal antenna and the sync jack. Saw it on the strobist flicker sight... but, have not tried it yet.

I have a similar problem to yours that could be related. What i discovered was that if the receivers were too close together, one or more of the flashes would intermittently not fire. Even though all the receivers would light up every single time, one of the flashes would not light and it was random which one. I have 3 flashes, 2x sigma 500 dg supers and 1 Sunpak 433AF. If I move them far enough apart, like 7 or 8 feet they work fine. Closer than 6 feet apart and they are flaky. If I am in really close quarters, then I have to resort to using 1 receiver attached to the Sunpak driving the Sigmas in optical slave mode. The proximity of the transmitter plays a part in it as well by adding some wonderful RF waves into the mix. Annoying.. but something I can live with until I can afford non-poverity wizards.