Vignettes in Photoshop and ACR + Lightroom Vignettes are extremely powerful tools for grabbing your viewer’s attention. They can very quickly make an ordinary photo look incredible! But, there are some problems with traditional vignettes.
1. They can look too contrived if not blended well.
2. Traditional ACR or Lightroom vignettes don’t give you a whole lot of control.
3. Sometimes it just looks like a giant ring around your photo.
Read more and watch the two video’s: A Different Look at Vignettes – f64 Academy