Hi Gang....... I seemed to remember asking this once before but I sure don't seem to recall ever getting a reply. On the Vivatar 283..... Does the large calculator dial actually do anything to the out put of the flash? I ask this because on one of my units the dial moves quite freely and on more than one occasion I have shot most of a role where the dial moved to a way different ISO than the film speed that I was actually using. On all occasions film came out quite well. (maybe it was just do to the latitude of the film?) I was thinking of using one of these guys on Auto for out door fill flash. But if the dial is only a calculator.... It does make things a bit more interesting! Russ R.E. Baker Photography rebphoto@pronetisp.net