Simply, real fresco is, pigment painted into plaster as it is drying, still wet. Dry fresco is painted into dry plaster.
After it is dry,
Dry fresco is done with real plaster, not drywall mud with color. Or over sheetrock,
You get one shot at Dry fresco; paint over paint is not dry fresco, or any other fresco. If you have paint or color additives mixed in your plaster, it is not a fresco. Paint over paint defeats the whole concept.
Frescos are to INBED the pigment.
To become a part of the plaster, 99.99999 % of all so called Frescos in the U.S. (restaurants, custom homes, and hotels) are NOT FRESCOS they are cheap imitations. That is a FACT.
Almost all, so called designers in the U.S. HAVE NOT A CLUE in regard to frescos. Most so called plasterers, and drawlers, claiming to do frescos, and, or Venetian plaster have NO CLUE.
I go into homes and business all the time and, people will say look at my VENETIAN PLASTER OR MY FRESCOS I had done. I want to vomit.
My line I tell all of them is this; Go to Venice, and show them photos of your frescos or Venetian plaster. You will probably get slapped.
Product # 6. Frescos Real and Dry Instructions