In article D8v1h.6617$Wy6.4568@trnddc01, dadiOH
wrote:

A lot depends on the lightness/darkness of the things in the photo. A
black vignetter essentially burns in the edges/corners making them
darker. A white one does the opposite. A translucent one sort of
smears those areas. Which to use depends on what you want to achieve.
Skin color is unimportant.

I always used a professional lens shade, and then used Larson
vignettes. They're magnetic and made of a dark mesh. They worked great,
but don't know if they're still available.