Cloud base tutorial

cloud base parameter

This parameter shows the height of the underside of low clouds. The purpose of it is to specifically go photographing in the fog. If you go to a mountain that is higher than the specified underside of the clouds, you are in fog. It is then possible to take exciting photos in the forests covered with fog.

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Color overlay

The loading of the color overlay is indicated by a small loading symbol at the bottom right of the map after selecting a time. If there are currently no clouds below 1500m in your region, then nothing will be displayed on the map.

If there are clouds below 1500m at a location at the selected time, then the color overlay will be displayed there.

The color overlay can be translated into a numerical value using the scale.

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The background map

To be able to see the altitude of the mountains in a region, the background map “Outdoor” should be selected. This can be changed at the top of the menu bar. On the background map “Outdoor” the contour lines can be seen. By comparing the contour lines with the indicated height of the cloud bottom through the color overlay, it is possible to see which peaks will be in the fog.

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Choosing a photo spot

If you want to visit a photo spot, it must of course be higher than the specified cloud base, because then the photo spot is in the clouds. For this you use the contour lines again. Compare the view marker on the map with the contour lines to see how high the photo spot is.

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Resolution of the weather model

The weather model has limited resolution and cannot capture all the details of the landscape. For this reason, you will have to interpolate a bit. This means that you should view the color overlay in the area around the desired mountain peak and not only directly at the location of the mountain peak itself. In the radius of a few kilometers the height of the cloud bottom hardly changes.

Further, it is the case that the tops of mountains can peek out of the clouds. In this case the top would be higher than the bottom and also higher than the top of the clouds. This can be seen well in the example shown. The 1800m high peak “La Nuda” looks out of the clouds, while in the surrounding area it is shown by the color overlay that the cloud bottom is 1300m. So if you were to visit the mountain, you would be standing in the fog from an altitude of 1300m.

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Common things about weather forecast you should know!

Computer Simulation

The weather forecast in VIEWFINDR is a computer simulation that very realistically forecasts the coming weather. However, the forecast is not exactly the reality and there will be deviations.

In VIEWFINDR new weather data is provided every 3h. For example, if you check for the probability of afterglow after sunset in the morning hours, the forecast will change several times over day. This is perfectly normal and that’s a good thing!

The closer the deadline, i.e. the sunset in the evening, the smaller the deviation of the computer simulation from reality becomes. The forecast becomes more precise. Before you finally set out to take pictures, you should therefore take another look at the current forecast.

You should therefore check the forecast again before you start your photography tour to see, if the probability is still high. Don’t be mad if the forecast probability changed into worse, it probably saved you from a bad outcome!

The weather forecast in VIEWFINDR is limited to 24h for local weather models and 72h for continental weather models. It is not useful to look into the future for a longer period. The forecast becomes inaccurate and is not reliable. Weather apps that allow forecasts of more than 3 days but do not provide any indication that the forecast is extremely inaccurate are a disgrace. This gives the

Weather Data Resolution

Just as the resolution of your camera is limited, i.e. it cannot take an “infinitely” sharp photo, the resolution of the weather model is also limited. This is 2.8km for Central European weather data and 7km for European weather data.

Structures and features of the landscape that are not that large are averaged by the model. For example, if a mountain is 800m high, and the valley next to it is 400m high, then the landscape for the weather model in that “pixel” is 600m high, corresponding to the average altitude.

This means that small structures, like narrow mountain valleys or local small river valleys cannot be properly captured by the model. This is not a problem, you just have to learn to deal with it. If a valley in the mountains is much smaller than the resolution of our weather model, then you have to interpolate.

Small valleys always end in larger valleys. You can therefore use the weather in the next larger valley as a good reference for the weather in a smaller, adjacent valley. In the example, you can see that the large valley is filled with fog. It is almost certain that the small valley is also filled with fog.

Due to the limited resolution, it makes sense not to use too much zoom. It is important that you look at the overall context. Therefore, consider the weather forecast not only for your location, but at least for the entire region where you are shooting.

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This example show how the weather model sees the landscape. It is pixelated because of the limited resolution.

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Due to limited resolution, this layer of low clouds/fog will not indicate fog in valleys with a size below the resolution.