Vignette
Darkening (or lightening) the edges of an image so the frame quietly pushes the eye toward the center.
See it
What it is
It started as a lens defect: light falls off toward the corners of the frame, worst on wide lenses shot wide open. Photographers liked what it did to the eye, so it became deliberate. Now it is a soft radial gradient of darkness (or light) painted over the picture, pulling attention inward without anyone noticing a technique happened.
Best uses: hero images with text over them, where a vignette buys contrast at the edges without the flat grey scrim everyone reaches for; portraits, where it separates a head from a busy background; and video grades, where it is standard on nearly every narrative shot. A white or warm-colored vignette does the opposite job, giving an airy, faded, old-print feel.
Two traps. If you can see where the vignette begins, it is too strong or too tight: keep the falloff wide and the center generous. And match the shape to the crop. A circular vignette on a 21:9 banner crushes the left and right edges into caves, so use an ellipse scaled to the container's aspect ratio.
Ask AI for it
Add a soft vignette to this image: a radial-gradient overlay that is fully transparent across the center 60 percent and eases to about 45 percent black at the corners, shaped as an ellipse matched to the container aspect ratio rather than a circle. Use a very gradual falloff so no ring or hard edge is visible, keep the subject's face outside the darkened zone, and make it pointer-events: none.