Foil is a mirror
Hot foil stamping presses a thin layer of metal into paper, board or leather. Metal reflects like a mirror: what you see is mostly the light of the room around it, tinted gold, silver or copper.
Why foil mockups often look wrong
Because a mirror shows its surroundings, many mockups paint foil as a dark metallic gradient. Gold comes out brown and silver grey, while in a soft, evenly lit room real foil looks bright.
What changed in PreviewFly
Foil now takes its brightness from the light in the photo you chose, plus a highlight wherever the product has one. On paper, board and leather it matches how bright real foil looks in photos of real products.
Getting foil right
Foil stands out most against matte stock, where its shine is the only shine on the page. Very fine lines can break up when stamped, so ask your printer how thin a line they can hold.
Still open
Foil on fabric is offered among the “other methods” and keeps its older look until we have photos of real foil on fabric to check it against.