Something I try to keep in mind when making art that looks vintage is keeping a limited color pallette. Digital art gives you a very wide, Crisp scope of colors, whereas traditional art-- especially older traditional art-- had a very limited and sometimes dulled use of color.
This is a modern riso ink swatch, but still you find a similar and limited selection of colors to mix with. (Mixing digitally as to emulate the layering of ink riso would be coloring on Multiply, and layering on top of eachother 👉)
If you find some old prints, take a closer look and see if you can tell what colors they used and which ones they layered... a lot of the time you'll find yellow as a base!
Misprints can really reveal what colors were used and where, I love misprints...
Something else I keep in the back of my mind is: how the human eye perceives color on paper vs. a screen. Ink and paint soaks into paper, it bleeds, stains, fades over time, smears, ect... the history of a piece can show in physical wear. What kind of history do you want to emulate? Misprinted? Stained? Kept as clean as possible, but unable to escape the bluing damages of the sun? It's one of my favorite things about making vintage art. Making it imperfect!
You can see the bleed, the wobble of the lines on the rug, the fading, the dirt... beautiful!!
Thinking in terms of traditional-method art while drawing digital can help open avenues to achieving that genuine, vintage look!
ALSO!!
YELLOWING!! Digital art is very blue-light based. Cold, clean, flat. But traditional art has warmth to it. Why?
Over time, paper gets yellowed with dust, oil, dirt, and nicotine from cigarettes! So colors got warmer. This makes art look pretty aged, on top of the slight toned papers and hand made/factory made inks they printed with.
