Reddit reviews Faking It: Manipulated Photography before Photoshop
We found 2 Reddit comments about Faking It: Manipulated Photography before Photoshop. Here are the top ones, ranked by their Reddit score.
Used Book in Good Condition
The Met in NY had an exhibit called Faking It: Manipulated Photography Before Photoshop. I saw it, it was a great survey of they type of stuff you're asking about. It's currently at the Museum of Fine Arts in Houston. There was a companion exhibit of manipulation in the Photoshop age.
There's a catalogue of the exhibit which I think would answer all of your questions.
The short answer is people manipulated both the negative and the print, and made prints from multiple negatives. The results ranged from crappy to undetectable.
Also take a look at the work of Jerry Uelsmann, a master manipulator pre-Photoshop.
Late edit: Just stumbled across this 1955 article from Popular Mechanics called How to Make Incredible Pictures
There was an exhibit at the Metropolitan Museum of Art in NYC a few years back, called Faking it: Manipulation before Photoshop, which was a good overview of pre-digital photo editing. There is a book associated with the exhibition.
If that's not the kind of thing you're looking for, then please explain further.