What the Fog? Part One: Where To Expect Foggy Landscapes

Foggy, misty, and moody. Landscape photographs don‘t always need to be epic and colorful. In this article, I share a few tips on how to find foggy and misty landscapes.

It’s All About Water in the Air

Fog, mist, and clouds are terms used to describe quite similar phenomena. A higher amount of water droplets in the air affects visibility. While there is still a lot of light passing, some of it will be diffused and reflected by the water droplets. The farther an object is away, the less likely we can see it. There are simply too many droplets between us and the object.

Just like fog, clouds consist of uncountable small water droplets.

While mist, fog, and clouds all become visible as white and gray “steam” in the air, the terminology distinguishes location and density. Clouds are usually found high up in the air, while steam and fog are phenomena observed close above the ground. Weather experts call it “fog” when you can’t see farther than a kilometer, while “mist” offers you more view.

In colloquial language, these terms might be used differently. Denser mist is called "fog", that’s it. When you photograph mountainous areas, the barrier between fog and clouds will also disappear. Eventually, the terminology doesn’t really matter. Fog, mist, and clouds offer you a great opportunity to create some unique images.

Here are a few tips to help you forecast foggy landscapes.

Cold Air Can Take Less Humidity

Landscape photographers always have to deal with the weather, and the forecast is a good, but not perfect way to prepare. In my area, fog often appears on consecutive days. If I witnessed it one morning, I will check the weather forecast and prepare myself for the next day. You will also get a good feeling when the chance of fog increases by paying attention to your environment. A lot of dew on the ground is a good indicator, but there needs to be a little more to make the air be filled with droplets, too.

Fog often appears during a cold night and morning when the relative humidity increased at night. The term “relative” is important here, because the amount of aqueous vapor which the air can carry is dependent on the air temperature. The colder the air, the less humidity it can take. Relative humidity of 70 percent during a warm day results in more aqueous vapor in the air than 70 percent during a cold night. When the temperature is falling during the night, 70 becomes 80, 90, and finally 100 percent — without changing the absolute amount of vapor. At this point, the air can’t take any more water; there is no 110% relative humidity. The air is already saturated. The point of maximum saturation is called the “dewpoint.” 

To create really dense fog, you need humidity and decreasing temperatures.

When the temperature decreases below the dewpoint, the water-keeping capability of the air is further reduced, but the water is still there. It condensates into bigger water droplets and becomes visible to our eyes. At first, it will become a soft mist; later it will accumulate into dense fog in the air.

When Is Fog Most Likely To Happen?

To be ready for the big moment of moody photography, we need to watch out for higher differences in air temperature between day and night. The relative humidity needs to be already high, and the temperature needs to drop a considerable amount to allow enough water droplets to leave the air and appear as a mystic backdrop in our photography.

Even though fog is most likely to happen after a long cold night, it can also happen earlier as long as the air temperature is low enough.

While there is a chance of fog appearing throughout the year, fog is most likely to happen in late autumn through early spring. During the night, the humid air has more time to cool down and reach the dewpoint. If you ever wondered how to shoot beautiful landscapes during the colder seasons, fog is a great opportunity.

Other Forms of Fog

Besides the “ground fog” mentioned above, fog can also appear under different circumstances — for example, when warm and humid air hits a cold surface. As a result, the air close to the surface cools down and goes below the dewpoint. We all witness this kind of fog in winter. When we exhale our humid and warm breath into the cold air, it appears as “fog” until it diffuses within the surrounding air.

Clouds are also connected to the dewpoint. When water sources like the sea, lakes, or rivers get heated up by the sun, water vaporizes into the air. Because hot air always tends to go up, it moves higher into the atmosphere. Even though we can’t see it, there often is a lot of water in the air. It only becomes visible when it cools down far away from the ground. Clouds appear when the relative humidity reaches 100% and the air continues cooling down. At some point, the water droplets get too heavy. That’s why a weather-sealed camera is a good investment for landscape photographers.

The water doesn’t always need to rise up high to cool down. Especially at lakes, when the weather gets colder, we can often witness some steam on the surface. While the water of the lake is still warm, it vaporizes and meets the cold air above. Condensation happens, and we witness a fairy-tale-like mist right above the water surface.

Important Things To Consider 

Not talking about composition, settings, and editing yet, the fog comes along with some challenges. Especially in winter, a low dewpoint means that streets can get slippery. When we choose to get to our landscape photography spots by car, we should take special care. Getting up early and driving a car with poor sight and slippery streets isn’t always a problem as long as we know what we are doing and are focused on the street.

Our camera gear is also affected by fog and mist. Water loves cold glass and metal, which is basically what our gear is made of. Even though most modern camera bodies’ cases are made out of plastic and composite materials, their most vulnerable part, the lens, is still made out of glass. Shooting in the fog hence means constantly wiping your front element. If you keep your gear warm and wear it under a jacket, you can reduce the condensation on your glass, but you won’t be able to totally avoid wiping.

Finally, I can’t emphasize it enough: good shoes are quite important when shooting landscape photography. Not only do we tend to wander on slippery paths and step on wet rocks. We also walk through high grass and sometimes right into hidden puddles. Good waterproof shoes are a big relief when the air reaches the dewpoint and everything is soaking wet.

Log in or register to post comments

3 Comments

Never Mind's picture

I never tried them, so I cannot tell how well they work, but there are lens warmers to prevent condensation. And even some diy tutorials.

Rain under windy conditions is most annoying for me anyway. Switching lenses, getting the gear in and out of the bag, or having the lens covered while still being able to handle the controls can be a nightmare sometimes.

Musing Eye's picture

Thanks for the great summary. I often feel like I see the foggy conditions too late, such as when I'm already on the way to work when I could have gotten going a bit earlier and tried to get some photography in.

Jens Sieckmann's picture

Great article. Hoping for the next parts to dive into some practicals for online fog researches and tipps in the field.