Photographing in fog

Fog is notoriously difficult to photograph, and not just due to exposure issues.

Fog could be described as wet air.  Technically, it is a colloid, which describes any medium that suspends tiny particles that do not settle out easily.  Other colloids you may be familiar with include mayonnaise, smoke, milk, and paint.  The thing about colloids is that the tiny suspended particles scatter light, which is why you can't see well through them, especially if they are particularly dense.  Shooting in dense fog is challenging due to the lack of clear subjects.  As the density of fog decreases,  there is less scattering of light and elements of a scene begin to emerge.  

The thing to realize when photographing in foggy situations is that you will need to overexpose your images by one to two stops, more if it is warranted.  In automatic modes, that means using exposure compensation or exposure lock if you can find nearby objects that are not too washed out.  I often shoot in manual exposure mode, and I will find a neutral exposure setting and then overexpose the photos by the desired amount.  

Relying on a histogram will help you to determine a proper exposure.

I often will check my histogram, either through play after shooting or using a live histogram display in a mirrorless camera.  I can then make any necessary adjustments to ensure a proper exposure.  The other thing that I do is to shoot raw images (I do this for all my photos).  Raw files have more latitude and you can extract details that jpegs will lose.  The thing to keep in mind, though, is that shadows are easier to extract details from than blown-out highlights, so if you are going to make a mistake, it is better to underexpose rather than overexpose.

Another issue comes with the fact that fog makes everything wet.  The front of your lens will likely become covered with water drops if you keep it exposed to the elements.  A lens cap will improve your chances of keeping your lens clear of water droplets.  It is a good idea to also keep a good, soft cloth available to remove any water that does manage to make it onto your front element.

If you want to shoot in fog, shoot early in the morning, shoot near a body of water, and often in late summer or early fall.  Although fog can form throughout the year, I find that these are ideal conditions for its presence.  The day also has to be still; no wind.  The other great thing about fog is when it dissipates - you are often left with a brilliant blue sky and more ideal shooting opportunities.

Thanks for reading.

Eric Svendsen     www.ericspix.com