triple head mount with 580exii issue

[rdavison]

I have two 580 EX 2 flash and 2 Vivatar 285hv's.  I am using a triple head mount for 3 of the flashes and 1 flash as a rim light.

If I use a 580 only on the triple head as a master and the other 580 as the rim as a slave they both fire.  

If I use 2 580's on the triple head (master and slave) with a Vivitar as the rim with an optic slave trigger all 3 flash.  

BUT, no combination allows all 4 to flash.  

As soon as I put 2 Vivitars' and a 580 master on the triple head holder the slave won't fire?  If I put a master and slave and a Vivitar on the triple mount the slave 580 quits firing.  I can use 2 580's (slave and master) on the triple mount and then a Vivitar as rim and it works.  There is no connection electronically between all of these.  Just the light of the flash firing.  Any ideas?  

[RobertTheFat]

It must be some sort of timing issue. There are pre-flashes involved, aren't there? Maybe some particular sequences cause the flashes that haven't fired to get confused.

[rdavison]

Not sure about "pre-flash" but perhaps post flash.  It receives the signal from the master 580 which triggers others and the sequence confuses the other 580 no matter where it is in the order.  A lot of money to pay for a flash with such a shortcoming, wouldn't you agree?  

I appreciate your input.  Looks like I must live with this or try an optic slave on the 2nd 580.  Maybe that $8 technology is superior to that in a $600 flash?