The Photographer’s Ephemeris

tpe_expanded_500x500The Photographer’s Ephemeris (from now on TPE) is one of those apps that will help us to plan our sessions better. It is rather similar to Exsate Golden Hour, but it includes some differences that help to make TPE complementary, instead of an alternative. This program shows a map of the desired place, and overlaps a circular graphic showing the position of the moon and sun for an specific period of time. This way you can use it to plan a session knowing where will the sun be at the golden hour, or at what time the moon will be in an specific position to photograph it.

Compared to Exsate Golden Hour (EGH) it has advantages and disadvantages.


-As with EGH, there is an app for Android and iOS, so you can look at it anywhere. It requires a data connection in order to access the map. But it also has a desktop app, that you can access from your computer for free. For decisions made on the spot it is usually enough the mobile app, but for a good planning the big screen of a PC and the precise use of a mouse is an advantage.

-It takes into consideration the shape and altitude of the horizon (the terrain, in general), which is the best and most useful advantage of TPE over EGH. One of the problems that normal calculations have is that they consider the horizon to be flat. Many programs can tell you that an object will be visible just because it’s 10 degrees over the horizon. But if it happens that you have a mountain in front of you, that covers 15 degrees high in altitude, it will cover the object and the program won’t know about it. Also, sunset is achieved before the expected time when there are mountains around, and happens later if you are in the top of an elevation and the horizon is flat. TPE has all of this into account. Apart of the main point, that you set in your camera position, you have an auxiliary marker that you can set in different points of the map, and it will calculate the relative elevation of the point respect the main marker. The difference of altitudes, given in meters and degrees, allows simple calculations of the exact time for an event.

-Based on the altitude of the main marker, it can estimate the position of the real horizon. This way you can estimate which part of the scenario will be visible in your landscape, or in which range can be annoying a present object that might interfere with the expected picture. Everything outside of the horizon mark can be ignored most of the times.

TPE example
This example is settled in Byparken, a park in the center of Bergen. The city is surrounded by mountains. In this example, the annoying one is the one on the right: Fløyen. The predicted point of sunrise in the example is marked by the yellow line on the right, but this assumes a flat horizon. As the grey marker of the right states, the mountain at that point is 417 meters higher than the main marker (the red pin in the center). As the information bar states, that supposes an elevation of 8.37 degrees. The thin orange line on the right shows the point when the sun will be over the real horizon. The official sunrise happens at 05:24, but the real one happens at 06:51, almost one and a half hour afterwards. The exact point where the sun will rise was calculated by trial and error, but it took a couple of minutes: Set the marker on the highest point and calculate the time the sun will be there. If the sun is higher than the point, move the sun until its altitude equals the grey marker. Now move the marker to that position, if the sun is now lower, repeat the procedure until there is no variation.


– Although both programs include information about sunrise, sunset and twilight, EGH adds more information, like the exact range of time that the blue hour lasts, or the time of the golden hour.

– TPE lacks of predictive behavior. You cannot set some rules and predict when will be a good moment to take the picture. In TPE you have to look at the data manually and predict the desired conditions, time and place moving the dials.

-TPE doesn’t include meteorological forecast. The predictions in EGH adapt to weather conditions like clouds, rain or clear skies. In TPE you have to take care of this parameter on your own.

So, after seeing all of this, the question is which one is the better to use. My decision is clear: both of them. They are free and they act as a complement of each other. I usually use TPE when I have to plan for a new place. It allows me to know the terrain, and to take care of what I really want to do. Once I have chosen the place and the time, I use EGH to refine the moment, to set a condition for the weather or repeating times when the event will happen. In a sentence: I use TPE to discover new places and find where and when I want to place my camera, and I use EGH to remind me of every time my desired conditions are met, and to refine them to include additional parameters.

Do you know any other programs or apps that are similar? Just tell us in the comments section!

Ease of use: 4.5 / 5 (The higher the better)

Specificity: 4 / 5 (Higher doesn’t mean better)

Applicability: 4.0 / 5 (Higher tends to be better)

Name: The Photographer’s Ephemeris

Producer: Crookneck Consulting LLC

Platform: Android, iOS, Desktop.

Price: Free

Download: The official page (Links to every platform) , Direct access to the desktop app


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