[LargeFormat] Pre-exposure in the real world

[Cindy and Marco Milazzo]

I said I was full of questions about practical issues.  Here's my first
one:

In his books, Ansel Adams advocates pre-exposure as a way to control
contrast and punch up the darker values. I've tried it, and it works, but
it's somewhat dificult to accomplish in the field.

Do any of you pre-expose, and if so, how do you do it? Are there any
tricks or gadgets that help?

TIA

Marco --
On an overcast El Paso morning