Using The Photographer’s Ephemeris

Fortune favors the brave.

Faint heart ne’er won fair maid.

To those two and countless others, I”ll add one more, if it’s not already out there: Fortune favors those who do their homework.

In this post I’ll be moving step by step through doing my homework with The Photographer’s Ephemeris (TPE). I’ve mentioned this excellent program before, and in the first half of my previous two-part post I mentioned TPE as one of my usual tools. I thought today I’d present an example of how I use it prepping for a field trip.

TPE is free, so there’s really no reason not to go check it out.

First, those of you that might want to follow along hands-on, go to the TPE download site and it will walk you through the necessary downloads (2 downloads: Adobe AIR and TPE). Installation is quick, simple, and painless. After TPE is installed, it will come up centered on Timbuktu. I don’t know if that is a place particular to the author of the program or if it’s a tongue in cheek joke, but I found it humorous. Since I don’t know if those reading this will have any familiarity with the program at all, I’m going to be as step-by-step as I can to help you get going.

Now let’s get started. This is a typical start to a planning session for me….

Yesterday, the Friday after Thanksgiving (29 November 2013 for those that don’t know the US holiday Thanksgiving) I went fishing with my son and his wife. We were down on the Snake River, first above then below Swan Falls Dam. Fishing-wise, it was a fun time, though a bit nippy, but no luck catching anything. As ever, I kept my eye out for photography ideas and at first I was thinking it was too bad there was so much haze, but after a while I saw how that haze was enhancing objects in the distance, really emphasizing how far away they were. Another thing I noticed was the shadows climbing up the canyon walls and how orange the walls got as the sun set. My thoughts wandered to doing a time lapse…maybe get there before sunrise and start shooting until after dark. On the way back, I happened to look up the canyon and thought what a great shot that would be with the canyon walls and the distant, hazy mountains, more visible by their ridges and dark shapes than any mountainous detail. Like a fool, I didn’t ask my son to stop so I could grab a quick GPS position.

The next morning I couldn’t stop thinking about the time lapse. The more I thought about it, the more I liked the idea. I decided to make it a project for when I was on vacation in December.

I fired up TPE, and set to work to find out what the times were, what the angles were, and where in the canyon I’d want to set up for best effect.

TPE does not use tabs to indicate the different parts of the program, nor does it use a toolbar. Rather, options and selections available are part of the really nice, clean, display. So, to get to the different tools, you click on the word itself, as presented across the top of the right half of the screen: Ephemeris, Locations, Configure, Glossary, and About. Other tools are available at various, fixed positions in the window and are selected by clicking on them, if available. They’ll be grayed out if they’re not available.

The first thing I did was click on the word Locations and check my entries. I didn’t have the dam there, so I typed into the search box under the map display Swan Falls Dam, Idaho, USA and hit return. That promptly centered the map on the dam site. With the Locations page still open on the right, I clicked on the button lower right marked ‘+’. That brought up a pop up that prompted me with a name for that location. I accepted the default suggestion but after saving it thought I’d prefer a different name. A single click on the name in the listing allowed me to re-name it Swan Falls Dam, Idaho.

Initial view after searching for Swan Falls and saving to Locations.

Initial view after searching for Swan Falls and saving to Locations.

I prefer to work either Terrain or Satellite view, since I want to see the details of the land, obviously, so I know where to point the camera, when and where to expect sunrise, moonrise, sunset, and moonset. So the first thing I do is set the map to Satellite so I can start looking for possible shoot locations I want to try. To do this, I click on the box Satellite at the top of the map display.

Satellite view of the same image.

Satellite view of the same image.

Now that I can recognize the places much easier, I click on Ephemeris at the top of the listing. Clicking on the hands pointing down and up in the middle of the screen, I start looking at dates and times to see what might work for me. I’m looking for a December shoot, and I idly notice that December 21 is on a Saturday. The significance of that escaped me for a minute, then I realized that I’ve been looking for an opportunity to shoot sunrise in a canyon for a long time…on the Winter Solstice. A quick google shows the solstice is December 21, 2013, 1711 UTC, or locally 1011 MST. Now I have three critical times for my planned shoot: December 21, Sunrise, and 1011 MST. I need to do the time lapse to include sunrise at my location, which since I will be in the canyon will be different from sunrise seen up on the rim of the canyon. I also want to, for the heck of it, include 1011 MST as one of my must-have shots as I know the sun has to be above the canyon rim by then.

Initial December 21, 2013 information and sun/moon rise and set lines.

Initial December 21, 2013 information and sun/moon rise and set lines.

Ok, now that I have all that, I need to find a good location. Using the Sunrise line (yellow) as a guide, I begin moving the red position marker around the canyon. If possible, I’d like to have the dam in the view, so I start by moving the marker downstream along the road, looking for an alignment between dam, canyon walls, and the yellow line. Starting with a high altitude view, I drag and drop the marker in several places until I find one that looks good. This one, I think will let me get everything I want:

Now this looks like a good location for the shoot...

Now this looks like a good location for the shoot…

Then I zoom in to set the marker where it’ll be safe: off the road a little while still giving me the view I want.

Zoomed in for a good, safe location placement. This is where I will set up my cameras.

Zoomed in for a good, safe location placement. This is where I will set up my cameras.

Zoomed back out now, to quickly check lines and dam location in the shot.

Zoomed back out now, to quickly check lines and dam location in the shot.

Now I zoom back out until I can see my selected location, the dam, and the canyon walls behind the dam. I know the sun has to come up over those walls, so it’s time to start fine-tuning my planning and get my times down. In addition, I see the moon will be behind me throughout the shoot and so not an issue. I already know, from the figures above, that sunrise is at 0814 MST. More importantly, though, I know that is not the time the sun clears the canyon walls. Sunrise, or more properly rim-rise, at my selected spot is going to be later, and that means one more important thing: the effective sunrise location for me will not be right on that yellow line indicating the direction of that day’s sunrise. Experience tells me it’s going to be more south than that, but how far south and at what time? That’s what we’ll find out next.

Down at the bottom under the list of days is a “button” that reads Details. Clicking on that brings up two very useful tools: the Grey marker, for lack of a better name, and a time slider.

The Details view, showing the wealth of data available.

The Details view, showing the wealth of data available.

Close-up showing the slider and altitude data used to determine the actual time of sunrise over the cliff rim, and the location of that sunrise.

Close-up showing the slider and altitude data used to determine the actual time of sunrise over the cliff rim, and the location of that sunrise.

This close-up shows the information that will drive the next step. The time slider is that triangle on the line next to the -90 degree at the bottom of the graph. The Grey marker information is in the bottom block, and you can see the apparent altitude above horizontal for the cliff rim and thus the effective altitude of the horizon at my location is +7.3 degrees. That means the sun has to rise at least that high above the projected horizon before I’ll see it from where I plan to be (the Red marker). Looking up at the block next to the time (08:12) you see the sun shows an azimuth or direction from north of 121.7 degrees…that is the direction of the yellow line on the map. That’s useful to know if you need to use a compass or other device to tell you where to expect the sun to be. It also shows an altitude of -1.2 degrees, or 1.2 degrees below the horizon at my location. It being faded out is also indicative that it’s below the horizon relative to the Red marker. So, at 0812 MST the sun isn’t yet visible, nor is it lighting up the canyon. This altitude of the sun is what we are going to work on, using the triangle to adjust the time.

Clicking and dragging the triangle, we adjust that until the altitude for the sun matches or exceeds very slightly the apparent altitude of the Grey marker. That is when the sun will break above the canyon rim. Adjusting that gives us a time of 09:11 MST. That is when I’ll have the sun rising above the canyon rim, and is another time I want to get a shot of: the first light of the Winter Solstice sun breaking over the canyon rim.

That thin yellow line below the sunrise line is where the sun will actually rise over the rim in the satellite view.

That thin yellow line below the sunrise line is where the sun will actually rise over the rim in the satellite view.

I’m sure you noticed that as we slid the slider, a thinner yellow line moved out from the yellow Sunrise line. That shows the position of the sun at the time the slider is at. You can see that, as expected, it is south of the Grey marker. My next step is to move the Grey marker onto this thin yellow line so that I can ensure the time is accurate and also to verify that from my position to that point on the rim I still have the sunrise in view. I click and drag the Grey marker onto the new yellow line, then zoom in on that spot to ensure I’ve actually dropped it on the rim and not the side of the cliff or back from the cliff. Alternating between the Satellite and Terrain views enables me to place it pretty accurately on the high point at that location on the canyon rim. I notice that also changes my altitude to the rim down to 5.1 degrees, indicating that now the sun will be breaking over the rim earlier than 09:11. I know that because at this point the altitude given for the sun, +7.4 degrees, is higher than this +5.1 degrees indicated for the Grey marker on the rim.

Initial adjustment of the Grey marker, starting the back and forth described in the text.

Initial adjustment of the Grey marker, starting the back and forth described in the text.

Now I hop back and forth performing the above steps to identify just when the sun should become visible. I adjust the time slider to get the sun’s altitude to match the new apparent altitude from my location to the canyon rim. With each change in time, until I’m satisfied, I repeat the slider movement, Grey marker movement, and recheck the sun’s and Grey marker altitude readings until they’re matching and the Grey marker is on the thin yellow line indicating the sun’s position at that time. Now I know the sun will begin rising above the rim at 08:56 MST.

Alignment and time determination complete! December 21, 2013 at 08:56 AM MST the sun will break over the rim as viewed from my chosen photography shoot location.

Alignment and time determination complete! December 21, 2013 at 08:56 AM MST the sun will break over the rim as viewed from my chosen photography shoot location.

Satisfied with everything, I now save that location, in this case as Swan Falls Dec 21. The steps are the same as before, change to Locations, click the + button, name, and save. I want to be there, and set up, and shooting my time lapse before 08:56, obviously, but now I know how much earlier I will need to be at the location to be ready to shoot and can easily plan for that. But that doesn’t give me much time before the sun breaks over yonder rim. So just how early do I want to be there and shooting the time lapse?

We know, of course, that the sun lights up the area before it rises above the physical horizon. So, to gain some additional idea of the time I want to be on site, I click back on Ephemeris, then click on Multi-day down near bottom right. That brings me back into the calendar view but now it also makes the Twilight button available.

The three twilights to help me determine when I need to be there....

The three twilights to help me determine when I need to be there….

Clicking on the Twilight button gives me the times for Civil, Nautical, and Astronomical twilight. Wikipedia gives an excellent description of the three so I won’t explain them here. For this project, I don’t need to worry about astronomical twilight. Nautical twilight might be a nice time to start the time lapse, but down in the canyon as I am, I think as long as I am there when civil twilight begins I should be OK to set up and start shooting. I should still have some nice stars in the sky and enough light to start seeing things on the ground. Based on all this, if I get to the spot about 07:00 MST, I should be set up and taking pictures by 07:30 and for sure by 08:00 without having to rush in order to capture the Winter Solstice sun rising over the far canyon rim down the canyon behind Swan Falls Dam.

A picture I’ve dreamed about taking for several years now.

Another useful piece of data from the Twilight page, especially for time lapse work, is you can figure out just how long you’re going to be out there taking pictures. That’s important because it plays to how much battery power you need to have to cover the full time you want to photograph. I have two batteries that should easily cover the planned 10 hours or so. But to hedge my bets, I’ll be taking my charger as well and recharging the first battery as soon as it’s swapped out. I do also have an external 12V battery plus adapter that should last the entire time, but I’ve not yet tested it fully. The point here is, TPE can help you figure out your battery needs as well.

Above the map view, as well as in the Locations list, I note the latitude and longitude of that Red Marker spot where I want to be on December 21, 2013. Of course, I still need to go back to the canyon before December 21 with the GPS co-ordinates and scout out the location to make sure I can actually see the picture I visualize: Is the dam visible? Are any boulders or shrubs in the way? Where should I move to?

Now that I know where on the rim the sun will rise December 21, 2013, I can scout out my chosen location ahead of time to ensure I capture this picture the way I want, time-lapse or still shot. Once I scout the location, if I need to move, I’ll note the new GPS location and return to TPE to repeat the process to get the times for the new location right.

Most probably when the time comes I will use two cameras to ensure I get the sun at the moment of solstice as well as various shots of the canyon walls, etc., while the laptop controls the camera time lapse photography. This ensures I have the freedom to move around with at least one camera if reality doesn’t quite match TPE. That also ensures that whether or not the time lapse sequences capture the exact moment of sunrise over the rim, I will be able to capture that shot with the other camera. After all, my next opportunity for this will be a year later. Or in six months, if I can work the Summer Solstice. I’ll have to fire up TPE now and check that one out!

It’s really quite easy and quick, taking way longer to tell all this than it is to just sit down and do it once you’ve had a couple of practice runs.

I hope this little write-up explaining how I use The Photographer’s Ephemeris has inspired you to look into it. While I’ve used this tutorial to illustrate figuring out when to get sunrise over a canyon rim on a particular date in a specific direction from down in a canyon, there are many more ways to use this little program, from figuring when you have to be in place to catch sunrise or moonrise over a particular subject to when the light will be at the best angle to your subject and allow you to figure out where you need to be to capture that gloriously lit photograph.

I am very thankful that the author, Crookneck Consulting LLC, has made this freely available to us photographers. Be sure and check out the Android and Apple paid application versions as well.

Now if only the weather will co-operate on December 21st…that’s not too much to ask for, is it?

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