Fog can be used in an illustration to enhance a spooky mood and chilly atmosphere or simply as an effect to draw attention to the focal point.

My last two Hallowe’en specials for Green Corner have used fog, but each illustration has a very different mood.

The Red Riding Hood illustration has a subtly chilly, spooky atmosphere. The somewhat deserted path, the blood on the axe in Barudo’s hand, and the fog draping across the feet of the characters help reiterate the theme. The image is meant to be a little spooky, but not frightening.

In the Pop Idol illustration, the tone is much lighter, vibrant, and cheerful. Here, the fog is used as a stage effect to enhance the theme of a 1980’s inspired pop singer performing on a stage. With this image, the intent was to emphasize the fun and escapism that dressing in costume can bring.


It’s very easy to create fog in Illustrator using the feather effect.

My settings for fog:

  • Fill with 10% grey, reduce opacity to 40%.
  • To soften the edges, use Effect > Stylize > Feather.

    Depending on the size of the paths you create, you may need to adjust the feather radius, but I generally use around 0.2″ and find that softens the edges just enough. Remember to make your path larger than you want the fog to appear, as the feather makes the fill appear smaller.

You can also experiment with different colours, to suit your colour scheme and the mood of your image. This tip can also be adapted for creating wispy clouds.

Note: the feather effect does involve rasterization, but it will scale more smoothly than a regular raster image and output based on the document raster effects settings.

Look out for another Hallowe’en-related tip soon! Hope you enjoyed this one!