Vignetting is usually perceived as an undesirable effect of some lenses that darken the corners of the image. Sometimes, however, this effect can improve an image considerably by adding depth and by focusing the viewer’s attention. There are ways of adding a vignette in post-processing. For example, you can use Adobe Camera Raw or the Lens Distortion Filter in Photoshop to do this. However, this affects the image directly and cannot be changed or undone later. Thus, it is destructive. But there is also a very simple method for adding a vignette effect on a separate layer such that it can be switched on or off irrespective of the work that you do on the other layers. Its intensity can be easily adjusted through the layer opacity setting. In this recipe, you will learn how to apply a vignette to your images.
Requirements and Assumptions
I assume that you have already completed
- any transformation work (rotation, distortion, etc)
- the cropping of the image.
Either of the two will require that you redo the vignetting.
The process has the following general steps:
- We create a black fill layer and cut out an oval in the middle using a layer mask. This creates the basis for the darkening of the corners.
- We apply a large amount of blur to the layer mask to create a smooth transition.
- We lower the opacity of the fill layer to get a more subtle effect.
- Create a new fill layer via the menu “Layer > New Fill Layer > Solid Color…”. When you get to select a color, make it a solid black. In the example image, I created a vignette group for hosting the fill layer. I do this for structuring the project.
- Remove the layer mask from the fill layer if there is one.
- Choose the “Elliptical Marquee Tool” from the tools palette. Move the mouse pointer to the upper left corner of the image, click, drag to the lower right corner and release the mouse button. This will create an oval selection over the entire image. Letting the selection touch the four edges of the image is usually a good choice. Making a smaller selection (further away from the edges) makes the vignette larger and more visible. You should experiment to find the best selection for your image.
- Turn the selection into a mask using the “Add layer mask” button.
- Click on the new mask to select it, and invert the mask by pressing Ctrl-I. Now you have an oval hole through which you can see your image while the corners are solid black.
- Next, apply the Gaussian Blur filter (“Filter > Blur > Gaussian Blur…”) with a radius of 250 (maximum possible value) to the mask. Be sure to select the mask before applying the filter (selected masks have a white border around them).
- After the filter has been applied, apply it a second time by pressing Ctrl-F (shortcut for applying the last filter again). Now your image is darker in the corners but you can see all the pixels of the original image and you have a very smooth transition from the dark corners to the middle of the image.
- Adjust the opacity (top right in the Layers palette) of the fill layer to a value between 30 and 60%. This will reduce the effect and make it more subtle. Remember, all we want is to direct the viewer’s attention to the middle of the image. He/she should not immediately notice the darker corners.
- You can place the vignette layer freely in the layer stack. It does not necessarily need to be at the top. In the example, I eventually moved it below the layer containing the sculpture. The effect is that the sculpture is not darkened at all. This may be useful for emphasizing the central element (in this case the sculpture) even more.
- The shape of the selection can be arbitrary. Try using a rectangle, for example, if that suits the image better.
Just experiment a bit.