Long exposure and studio strobes question

I am shooting with a Canon 5D Mk II and some standard monolights triggered via cybersyncs (full manual on camera). I'm experimenting with some night time car photography and light painting. Anytime my exposure is 10 seconds or longer, my monolights fire more than once. If my exposure is 15 or 30 seconds, they fire 3-4 times.

Is there a setting I am missing to have it only fire once?

Thanks for the help!

I'm stumped...

I'm not sure if setting it to 2nd sync would help, but you could try.

I notice that several triggers tend to act upon any sort of electrical impulse. When I use anything longer than 1/2 sec on my copal shutters, my flash fires twice - once when the shutter opens, and another time as it closes.

Also sometimes dirty or faulty sockets/contacts may trigger off repeated, intermittent firings.

James33 wrote in post #9940403
I am shooting with a Canon 5D Mk II and some standard monolights triggered via cybersyncs (full manual on camera). I'm experimenting with some night time car photography and light painting. Anytime my exposure is 10 seconds or longer, my monolights fire more than once. If my exposure is 15 or 30 seconds, they fire 3-4 times.

Is there a setting I am missing to have it only fire once?

Thanks for the help!

If you have more than a 10 second exposure you have plenty of time to just fire the flash units manually, you would not even need to connect sync to the camera.

This does not solve the actual question asked, but it provides a workaround if the solution is not discovered.

Enjoy! Lon

FlashZebra wrote in post #9943909
If you have more than a 10 second exposure you have plenty of time to just fire the flash units manually, you would not even need to connect sync to the camera.

This does not solve the actual question asked, but it provides a workaround if the solution is not discovered.

Enjoy! Lon

Lon -

You are correct! Still looking for an answer but that DOES help.

Thanks!