I have a set of 285's in the mailk right now and I was wondering If i need to buy anything extra to trigger these flashes off camera with a 7d or if the 7d pop up flash can do that? If so what what I need to purchase and what is the best bang for your buck option?
Not sure if the 7D has a manual mode without pre-flash, which would pre-maturely trigger normal optical slaves. There are also slaves that ignore the pre-flash but I've never used them personally.
When I used my pair of Vivitars I either used one on a bracket with an 18" Vivitar- PC cord, or on a stand with a 15' Vivitar -PC cord, with the remote flash triggered with a Wein Peanut slave.
Optical triggering works OK if you aren't around other flash shooters. The Peanut has a range of 100' and I never encountered signalling problems when using them.
FYI - The Vivitars have a proprietary plug that inserts into the base of the flash. There is a set of reed contacts in the base that disconnect the hot shoe contacts when the cord is inserted. The Wein Peanut is designed to either plug directly into the base or onto the end of a PC cord. I found it better to hand on the cord so I could keep it oriented towards the triggering flash.
That was a legacy feature from when the trigger voltage was 300+ volts on the older models. You can find the Vivitar - PC cords at Paramount Cords. If you don't see then on their web site give them a call and inquire.
sandman22 wrote:
I have a set of 285's in the mailk right now and I was wondering If i need to buy anything extra to trigger these flashes off camera with a 7d or if the 7d pop up flash can do that?
The pop-up flash always emits preflash pulses, even in manual mode, so it won't work with non-Canon flashes.
You could use a sync cord to trip one of the 285s, and fire the other one with an optical sensor like this one that has a Vivitar-style connector:
