The Photographers Ephemeris

Originally Posted: January 9, 2020
Updated: December 14, 2023


I first started using this tool over a decade ago to help plan for lighting conditions.

Over the past few years (especially during the Pandemic) I took a break from doing any real landscape photography; especially given travel restrictions and such.

In 2023, I started getting back into photography and re-visited this amazing tool and many of its enhanced features.

I shoot a lot of landscapes, and traditional skills tell you that you need to be in a place where the “light is at its best”.  Often, this means sunrises, sunsets, dusk, dawn, or, in my case, with the Rocky Mountains so close, high contrast shadows cast by the big rocks themselves.

Given my many years pursuing Astronomy, I am no stranger to ephemeris usage and data.

[1. ephemeris – In astronomy and celestial navigation, an ephemeris gives the positions of astronomical objects in the sky at a given time or times, see Wikipedia for further information.]

The Re-visit

With modern information and mash-ups available at our reach with our phones, tablets and laptops, this particular tool has become absolute in my camera bag arsenal (as much as a lens or camera body itself).

This tool allows me to locate myself anywhere on the planet and then position myself temporally on that spot at any time of day or night.  In combination with ephemeris information, it allows you amongst other things to see dawn, sunrise, day, dusk, and sunset in relation to the angles of the sun and moon associated with those moments in time.

With a little 4D spatial relations, one can put their “mind’s eye” in the location of choice and start planning accordingly, having the ability to have forecast data is a great option, I often balance this with the WeatherUnderground for planning.

It is great to have a theoretical place where the sun “should be” however it doesn’t help if you get out to the mountains and its overcast and blowing snow in your face with high winds !

Examples and Success

This tool has been utilized a number of times for some of the works I am most proud of (Canadian Pond Hockey for example).  While it does not take out all the work of having to find the location, scout it, or be at the mercy of the weather with a pinch of lunch and hard work, it does reduce the guesswork in determining when and where the Sun will be shining.

It should also be noted that this can have a great impact on those of us living farther from the equator where a sunset in the winder may occur at 16:00 whereas in the summer months at 21:30.  I’m not too worried about waiting around in the summer months, but take it from a Canadian, hanging out for several hours in -30 C weather waiting for the perfect setting can be a bit frigid.


The Photographer’s Ephemeris for iOS and other:

| Article posted in: Quantum of Light ||