I picked up a copy of a neat little book, this summer, in one of the many used books stores on Vancouver Island. It is Corrective Photography by Lewis Kellsey, put out by Deardorff (and signed by Merle S. Deardorff to John Palmer, who may be John E. Palmer, a photographer of Afro-Americans (principally) in Galveston, Texas in the 1940-1960 peiod).
Anyway, it got me working systematically to understand camera movements, and my question here is the degree to which the GG darkens as I tilt or swing the back.
It is a darkening that starts immediately with tilt and progresses as the degree of tilt progresses. This is not the question of compensation for differing reproduction ratios seen with extreme tilt/swing.
The lens is not obstructed, nor limited in movements. I use a Cambo (4x5 or 8x10 with 4x5 reducing back). Removong the back I can see the round lens in all 4 corners.
I understand I may be over tilting from usual practicality, but I have not read any reference to the back GG getting so dark with tilt/swing.
Is it normal for GG brightness to diminish progressively with rear tilt/swing?