Thanks for the clarification. The difference plus five means that if I get an EV of say 15 in the shadow and 18 on the highlight then I have an SBR of 8 right?

In the formula for the spot meter what value do I use for N or is it left as a letter? Would it look like this:
18-15=3 so D=3
(7*(3-N))/3

I was not metering a grey card. The shadow I wanted detail in when I first noticed this was under a rock where little rocks were holding it up. I have noticed this on many occasions. the difference between the two meters is only 3 tenths of one stop. When I was playing with the meter this happened again.

David
I like the ease of the Zone system and it really is a no brainer. There has just been so much hubbub about BTZS stuff that I thought I would give it a try. Being the obsessive SOB that I am when I can't figure something out I want to get this right.

I do not have a zone dial. Is this something I can make or does soeone sell them? It would definately save me some brain work because I do it all in my head right now.

Thanks for the help folks. I have found the BTZS book to be a bit complicated. It's times like these when Dyslexia sucks