John N. Wall , Jul 20, 2000; 03:44 p.m.
The F4 came out before Lithium AA batteries were introduced. When they went on the market, Nikon said, and continues to say, that they do not recommend use of AA Lithium batteries in the F4, that damage may occur.
No one knows what they are concerned about, but there is much speculation that centers on the fact that AA Lithiums have a little bit extra charge when the camera is turned on.
On the other hand, the manufacturer of AA Lithium batteries promises to fix or replace any unit damaged by use of these batteries. Pop Photo ran an article a couple of years ago in which they addressed this matter. They said they checked with NYC camera repair places and found no record of any damage showing up. They said they could see no reason not to use them in Nikon F4 and other older bodies that use AA batteries.
My local camera repair guy says he sees no reason not to use them. Several times on the 'net in recent years, people have asked for credible evidence of danger, with no response.
I use 'em in my 2 F4 bodies, and have for a while -- no problem. Your mileage may vary.