If we were to regard a watershed period as a period between two distinctly defined epochs, would the adjectives
be instantly recognized (by readers and/or listeners) as pertaining to, respectively, the former and the latter?
This is a post-watershed novel.
That's a pre-watershed painting.
I don't remember ever using pre-watershed technology.
Before the invention and commercial production of the paint tube, outdoor painting (known as en plein air) was rare. Paints were mostly made in the studio, either by the artist himself or his workshop, and difficult to transport safely.
A brief watershed period followed the introduction of the paint tube during which many artists found themselves adjusting to the new possibilities, after which landscapes were suddenly all the rage.
New techniques appeared and took root despite the numerous objections of some conservative critics. Today, some post-watershed paintings are valued as much as those of the Old Masters (including the entire French Impressionism movement).
Or is there a better term?