I have a 285HV and 283 and use both off camera in and out of the studio. Nothing I am going to say adds much to what has already been said other than that I use the various stuff suggested all the time without failures.
>> You can get any of several different radio triggers. They consist of a small transmitter that
>> goes onto your camera hotshoe and a receiver that triggers your flash. Prices for the models
>> commonly known as "ebay triggers" or "poverty wizards" are somewhere around $30 for a
>> single transmitter/receiver set. Prices for genuine Pocket Wizards are somewhere around
>> $400 per set.....with there being very little in between those two prices.
The V2 or V2S triggers work very reliably with the 285HV. Attach the 285HV to the receiver. Now get an optical slave for the 283. There are a variety of them out there, all cheap. I use the Sonia sensors (available on eBay) because they are modular and have a hot shoe with separate optical sensor attached. They are quite sensitive and do fine in broad daylight to reasonable distances. They also work very well at oblique angles... ie., they will often trigger even where they are 180 degrees out of the line of fire.
The shoe for the Sonias have a pc connection if you want to daisy chain other strobes. I have seen people more or less bungee two strobes together in a butterfly configuration and use the connector to fire the second one. Works well and throws a lot of light.
What I really like about the Sonia units is that the the sensor can be detached from the hot shoe and fits the end of your synch cord. In the studio I use the sensor on the shoe. In the field, I often let the sensor dangle from cord and attach the whole lot to a pole or something handy.
For something on the order of $55.00 or so shipped for the trigger. receiver and optical slave, you'll have everything you need and nice some flexibility too. On the other hand, you might consider asking the vendor of the trigger if you can purchase one trigger and two (2) receivers. I opted for the optical because for me this lends a certain amount more flexibility in certain situations... I suspect to that it's a little cheaper.
V2s Trigger and Receiver
Wireless Flash Trigger V2s for Vivitar 285HV DF-400MZ - eBay (item 170182315236 end time Jan-07-08 11:28:19 PST)
Sonia Optical Slave:
Sonia Optical Slave Flash Trigger/&Digital/Wireless - eBay (item 350010181429 end time Jan-03-08 12:30:10 PST)
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