Thanks one and all. I couldn't find a voltage spec on the 555 booklet; decided to go for it. And, yes, selected shutter speed (100 sec. equiv) and f/8 manually; the digithell camera is still working fine. The images looked fine, even in that dark restaurant; and, since I was using a strobe on a "L" bracket, no red-eye to try to remove.
Thanks again, for all your input.