Fog in Color Efex Pro 4 simulates a traditional fog effect, which is a soft focus that gives the appearance of fog. It can be used to enhance an existing landscape, or it can be used to add a dreamy look to your images.
To begin, take a look at the filter controls and see how they affect the image.
Fog filter control options
The Method drop down menu allows you to choose differing levels of the Fog effect. There are four Method options, and the filter is set to Method 1 as a starting point.
Method drop down options
Intensity controls how much of the filter is applied to the original image; 50% is the default value. Moving the slider to the left will reduce/remove any Fog that has been added to the image, while moving it to the right will increase the Fog.
Tip: Use Control Points to selectively apply the filtered effect to the image. You can use multiple Control Points to add or subtract the filtered effect from specific areas of the image, giving the illusion of a natural creeping fog. You can also utilize the Brush option, using Photoshop’s Brush Tool to paint/erase the filtered effect.