Vignetting Images in Photoshop
Vignetting Images in Photoshop - One of many ways
How do I add the Vignette effect to my images?
Vignetting a picture is fairly straight forward and looks great. However, it depends on what software you use at the moment. I will explain it as best I can, bearing in mind that I use Photoshop. Try to find the same terms and/or features on your program and try it yourself.
Open the picture and try to find an "Elliptical Marquee" tool or a lasso tool. The elliptical marquee would be better. Click on it and by dragging over the image; try to produce an oval vignetted shape on the image approximately where you want it to be. Once this is on your screen, you should have the "running ants" showing where it is. Then either right click your mouse on the area and "select inverse" or go to:
Select - Inverse
This will select the outside of the area. Now, if you were to darken this area it would look wrong as it would create a harsh line making it obvious. What you need to do, if you have the function, is:
Right click - "feather" or select - "feather"
This will literally feather or smudge the line so it looks realistic.
Select and try different values for the feather radius, but try 200 to start with. Once you have selected it, there are a number of things you can do to darken the outside of the picture. For now, go to Image - Adjustments and select either levels or curves, or any tool that adjusts tone, contrast etc.
Check the preview button and play around. You will see the Vignetting effect taking place and once you have the effect you like, stop and save it.