Trees...
It's strange how obvious masking of skies manages to become accepted as a kind of trademark, as it were. I'm not sure how much of his own printing he did, though he did it in the beginning of his career, but commercial work becomes something kind of separate from the complete artist, though on the other hand, even some so-called photographic artists hand it all over to a specialist printer...
Perhaps that's another reason for the doubts held about the place of photography within the world of graphic arts.
All that said, I find myself looking at his last book perhaps more than at any other one that I have on photographers, with just old Saul running a very close second. I don't have a Sarah Moon book, so that explains the running order.
:-)
Rob