Nikon 18-35mm f3.5~4.5, which diopter?

I'll be using an Ike housing with an 8" dome port. Ike has the standard +4 diopter spec for every lens that does not focus closer than 12". However this lens focuses to 1.1', so darn near.

Anyone know what magnification to get? I have no issue with getting a +4, but is that going to give me the best coverage, and is that magnification necessary?

Thanks in advance,

Ron

18-35...

I used the B+W +4 when i used that set up on my N90 (bet i just confused most people on the board with that camera... hehe)

was that an N90 or an N90x mate?

i used to have a +4 on my F80 with that lens.