Techniques Moments of Light Morning Glow Sunrise Animation Sunny 16 Rule Why Use a Tripod?

Morning and Evening light present some of the best Moments of Light of the entire day. Why? It's physics!

Have you ever heard photographers talk about "Alpenglow"? The Warm Light of Morning? Did you think they were out of their mind? Well, there really is a phenomenon that occurs early in the morning, and later in the evening, and it really can be easily explained. Well, that is if you think physics is easy.

A while back we all finally agreed that the Earth was round. I know, it was a pretty big step. Made some people angry too. But that's another story. The point is, the Earth rotates in space. It does other things too, but again - that's another story. As the Earth spins around, the sun appears to rise, wander through the sky, and then set. I'm sure this is not news to anyone.
Figure 1 – Where is the sun?
Earth, Atmosphere, and Sun Position – not to scale

Let's take a look at the sun relative to your position on the Earth at three different points in time: sunrise, noon, and sunset. The graphic (Figure 1) should show what is going on.

If you are standing at any point on the Earth, you can see that when the sun is on the horizon, either during sunrise or sunset, there is a lot more air between you and the sun! At noon, with the sun directly overhead, there is the least amount of air filtering the light. That's why you need sunblock 50 when you are out in the middle of the day; there is less between you and the sun's rays. So you need the extra protection. In the early morning, there is a lot more air filtering out the sun's harmful effects.

So, what is the point of all of this?

Because of the additional air filtering the light during the early morning or late evening, only the longer wavelengths get through. Here's where the physics comes in. Do you remember the colors of the rainbow?

The shorter wavelengths are on the blue side. (See Figure 2) The longer wavelengths are on the red side. With a bigger filter (lots of air) the shorter wavelengths get filtered out or dissipated. Only the longer wavelengths get through! So the "warm" reddish orange light of early morning or late evening is simply light that has been filtered! As Bill Nye would say, "It's science!".

Figure 3 – Sunrise Portal

You can see the difference that light makes by looking at the picture in Figure 3. This picture shows direct, indirect, and reflected sunrise light. The direct light from the early morning sun highlights the underside of the arch. Notice how brilliant the color is? The reflected light is visible on the stone wall seen through the arch... it is a more subdued version of the direct light. The indirect light on the visible face of the arch is the most natural look of the three. It is also the least interesting.

For more examples of morning glow, look at the tones of the rock in the three pictures below. The first one was taking right after sunrise. The beautiful golden glow of the early morning light is reflected on the rock formation. The next picture was taken during a rain storm, with no direct light from the sun. It shows the flat, reddish features of the stone.

The final picture was taken just minutes before the sun went below the horizon; the red light of sunset is reflected on the stone! This picture was shot on Velvia film (Velvia is known to be a bit "bold", but in this case I really like the effect.) The color of the rock is essentially the same in all three pictures! The only thing that makes the difference is the amount, intensity, and wavelength of light!

If you are wondering, the first and last of these pictures were taking during a trip to Arches National Park in 1997. The middle was taken during a Spring shower in Zion National Park in 1998. For a full version of the photos (they are cropped a bit here) you can review the Trip Tour of Arches National Park.

Morning on the Organ Arches National Park	Zion in the Rain Zion National Park	Sunset on the Delicate Arch Arches National Park

For a more dynamic example of Morning Glow, you can check out this animation. You should wait for the entire image to download; it may be a bit jerky at first. It shows the events leading up to the sunrise picture there on the left.