Mark, buy a copy of the book and read pages 298-303. Blaker explains what you want to know. I'm not going to type it for you.

Why do you think I'd give advice that couldn't be acted on? Do you have any idea how insulting you've been? I have the book. How do think I could give page numbers? We're not all as ignorant as you.

Be skeptical of old wives' tales and don't propagate them.

What motivated you to try the stacked lens approach? I ask because as I understand it it gives fixed magnification. Fixed magnification is rarely appropriate, not all subjects are the right size.

Quote Originally Posted by markjames View Post
Yes there are some second hand copies available but as I understand it the formulae are in a booklet that comes with the book and this is the sort of that is bound to be lost from a second hand copy.

All I want to know is how I correct the measured exposure when I have a second lens mount on the front of a camera with no TTL metering.