Let VIEWFINDRs clear night sky algorithm guide you to success. Forecasting a night without clouds for astrophotography is now easier than ever. Simply choose a photospot on the map in an area with a high probability of a clear night sky and visit the photospot by the time you can see on the scroll bar. The higher the probability, the lesser the clouds.
We use 3D cloud data to calculate the probability. We do not only check the cloudiness at one place itself, we calculate the distance of surrounding clouds. Hence a high probability tells you that there are no clouds at the place itself, but also around. This game-changing algorithm guarantees that even deep sky targets closer to the horizon won’t be affected by clouds.
The forecasts are hourly. Scroll through time and check for areas which have a high probability for clear night sky all night long to be extra sure. The better the map is visible, the higher the probability.
Tap on photo spot icons inside the chosen area of high probability. If you like the small preview, tap it. On the now open photo spot view, scroll through the images and check if the spot fits your needs. If so, just start the navigation.
This parameter guarantees a starry sky without disturbing clouds in the sky. Compared to conventional weather apps, this parameter not only takes into account the clouds at the exact location of the photo subject, but also the clouds in the surrounding area. By including the 3D clouds, it is guaranteed that the horizon is also free of clouds.
Like any parameter with a gray color overlay, this is a template parameter. Areas where the map is clearly visible have a high probability. Areas where the map is grayed out have a low probability.
Based on the visualization we use, the “Streets” and “Outdoor” background maps provide the best contrast to see the color overlay well. The background map can be changed at the top of the menu bar.
The scale can be used to translate how high the probability is. Simply compare the map with the scale and read off the value. Please remember: a probability of 20% means that you will come up empty in 4/5 cases!
By scrolling the time scale you can change the date. An up arrow marks the sunrise, a down arrow the sunset on the respective date.
In the highly visible areas of the map, the probability of occurrence of the weather phenomenon is particularly high. Pick out photo spots in these areas. The weather overlay covers the photo spots up like a template. The better a marker can be seen, the higher the probability for the weather phenomenon to occur at this specific photo spot.
By setting the filter in “Views” to “Weather specific”, only those photo spots will be displayed that can be photographed with the selected weather phenomenon.
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
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.
This example show how the weather model sees the landscape. It is pixelated because of the limited resolution.
Due to limited resolution, this layer of low clouds/fog will not indicate fog in valleys with a size below the resolution.
When uploading a new photospot you guide other photographers. Connecting a photospot to the clear night sky parameter is not “making a wish”. Only connect photospots which actually can be photographed with a clear night sky. Do not link photospots in cities and other highly light polluted areas to this parameter.
We not only calculate the clouds at the photospot itself, we also regard clouds in a greater distance. The greater the altitude of the cloud, the further the distance needs to be for the cloud to not be visible in the night sky at your photospot. Or 3D algorithm uses cloud coverage and cloud altitude to make sure no cloud is bordering your astrophotography.