For at least the Pannys, if you want to trigger an off camera strobe, your two choices are radio triggers ($$) or a small cheap strobe in the hot shoe. If you search "Panasonic preflash" you'll probably find a few threads explaining the issue. My choice is to use a Vivitar 2400M, which I found on a "deal" site months ago for about $12 IIRC. As a horrible cheapskate, I was pleased. No more. Today only, if you go here http://1saleaday.com/flash/2400m/ they are selling for $3 shipped.