If, as I suspect, this is the one with the lettering visible when you look into the front of the lens, I believe the "S" just means the lens is in a Seiko shutter but is otherwise identical to the Copal-shuttered version. My old Fuji catalog (late 1970s) says 305mm image circle at f/22. It should just hit the corners of 8x10 at infinity, but you'll need to be careful about centering. At moderate distances you'll begin to get a little movement. I've used one on wholeplate, it's the widest lens I've got that'll cover the format.