piterengel wrote:

Hi, I'm waiting for the arriving of a Zenzanon macro lens, I've
ordered it and soon it will be here. I have a question. Because I've
not an AE prism finder, how can I calculate the right exposure when
lens is completely extended to have the maximum macro efffect? Are
there tables for this?
Thanks all

Very useful. So, if I have a 1:1 macro, x=4 so I have to increase
exposure of 2 stops. Right?

Have a look at this page:
http://www.hasselbladhistorical.eu/HT/HTComp.aspx

Don't let the theme of the site throw you off: the basic calculations are
the same for all lenses.

Only when you want to take lens asymmetry into account, you will need
Bronica specific lens data.
But the general formulae usually get you close enough, no worries.