The Beginner's Guide to Astrophotography: How to Capture the Cosmos with Any Camera

1

What Is Astrophotography?

Congratulations—and welcome! You have just taken the first step in a lifelong journey that will take you to the furthest reaches of space. This book will teach you to capture incredible images of distant galaxies, the Milky Way, gas and dust nebulae, star clusters, and so much more.

Welcome to Astrophotography!

I distinctly remember a moment over thirty years ago that changed my life. I stopped by a bookstore on the way home from a weekend trip with friends in California’s Anza-Borrego Desert State Park. Inside, I leafed through a special annual issue of one of the major astronomy magazines and came across an entire section explaining how to do astrophotography with a regular camera. I felt like I had been hit by lightning! I instantly realized I could start my astrophotography journey with the gear I already had—if I only knew how.

In many ways, that epiphany was the catalyst for the book you now hold in your hands. I hope you can experience the same rush of excitement the moment you realize that you, too, can capture fantastic astrophotography images with the gear you already have. This book will show you how.

Types of Astrophotography

There are two main types of astrophotography: deep-sky astrophotography (chapter 5) and landscape astrophotography (chapter 4), also known as nightscape photography (Figure 1.1). This book covers both.

Figure 1.1

Deep-sky astrophotography images feature only the night sky with one or more deep-sky objects, such as a galaxy, nebula, or star cluster. Landscape astro-photography images, or nightscapes, feature the night sky with an interesting foreground. Landscape astrophotography images often showcase the Milky Way, the moon, constellations, meteors, or the Aurora Borealis/Australis, along with mountains, lakes, or city skylines.

Where Do I Begin?

You can get started in astrophotography no matter where you live, whether deep within a city or out in the countryside (Figure 1.2). City dwellers can observe and photograph constellations, the moon, Jupiter, Venus, Saturn, and Mars rising or setting over iconic city skylines. Residents of rural towns far enough away from the city to escape its brighter lights can begin to capture the faint outlines of the Milky Way, along with familiar stars and constellations. Finally, residents of and visitors to dark-sky locations can enjoy unparalleled views of the full richness of the night sky—glowing gas nebulae and star clusters within the Milky Way and even distant galaxies far beyond our galactic home.

The theme of this book is that you can do awe-inspiring astrophotography nearly anywhere. You don’t need to travel to a remote desert wilderness; you can enjoy a lifetime of astrophotography from your home.

Figure 1.2

You can do astrophotography in the city, suburbs, or wilderness. Here are astrophotography images from central Minneapolis, Minnesota, all the way to the remote Boundary Waters Canoe Area wilderness in the extreme northern part of the state: (a) Orion is visible over iconic downtown buildings in the heart of Minneapolis, Minnesota; (b) star trails shine in the morning sky over Duluth, Minnesota; (c) Comet NEOWISE appears over a suburban lake within the Minneapolis metro area; (d) the Milky Way, as seen from a rural location approximately one hundred miles north of Minneapolis; and (e) the Aurora Borealis dances over one of Minnesota’s ten thousand lakes at its far northern edge.

(a) 24mm, ISO 400, f/6.3, 1.6 sec

(b) 24mm, ISO 400, f/5.0, 1 sec

(c) 135mm, ISO 6400, f/3.5, 4 sec

(d) 70mm, ISO 12,800, f/2.8, 8 sec

(e) 48mm, ISO 12,800, f/2.8, 4 sec

What Can I Do with What I’ve Got?

Even a decade ago, high-quality astrophotography images were only possible with equipment costing thousands of dollars. But, thanks to advances in cameras, lenses, and image processing, an astrophotography revolution has occurred. Now, even entry-level cameras can perfectly capture stunning images of the night sky.

Figure 1.3

Compare these astrophotography images made with my hand-held Apple iPhone 12 (a and c) and my Nikon DSLR (b and d) during visits to Mono Lake, California, in 2022. Smartphone images like these were inconceivable even a few short years ago.

(a) iPhone 12 Pro

(b) 19mm, ISO 3200, f/2.8, 10 sec

(c) iPhone 12 Pro

(d) 24mm, ISO 12,800, f/2.8, 10 sec

Smartphone Astrophotography

Today’s smartphones have transformed astrophotography. You can now use them to routinely capture extraordinary images and even real-time videos featuring the moon, stars, planets, the shimmering Aurora, and the Milky Way (Figure 1.3). And what’s even more remarkable is that most smartphones don’t require the use of a tripod! Chase Jarvis’s quote, the best camera is the one that’s with you, perfectly captures the essence of this new era of astrophotography.

I suggest using your smartphone with its night mode (if available) to try capturing astrophotography images on every possible occasion. Sure, you won’t be printing the results as massive, three-by-four-foot trophies, but you will bring home some great images of memorable experiences. In addition, you’ll learn a great deal about what it’s like to photograph the night sky, and then decide if astrophotography is for you. And you never know, you might just tap your smartphone’s shutter button at the precise moment the meteor of the century streaks through the sky!

3, 2, 1, BLASTOFF!

Astrophotography opens the door to a lifetime of adventures as an astronaut (Figure SB.1.1). Yes, you read that correctly! Your views of space are no different from those of astronauts orbiting Earth. Allow me to explain.

Figure SB1.1

My spaceship is my camera and tripod aboard spaceship Earth. I use them to explore space as an astronaut. Do you have a camera, too? If so, I bet you didn’t know you are also an astronaut!

Figure SB1.2 shows two images of the same region of space within a week—one from Earth and the other from aboard the International Space Station (ISS). As you can see, the images are nearly identical! And this is no surprise. Sure, the ISS astronauts are roughly 250 miles closer to the stars than those of us on Earth since that is their orbital altitude, but let’s put that distance into perspective.

All the labeled objects in both our images are at immense distances. Even the closest star to Earth, Proxima Centauri, is still twenty-five trillion miles away. That means that the Space Station astronauts are only one billionth of one percent closer to Proxima Centauri than those of us on Earth. Consequently, on a clear night, your view of the night sky is no different from those aboard the ISS. You, too, are an astronaut…traveling through space aboard spaceship Earth!

Two more examples of astronauts orbiting Earth having the same views of space as us earthly astronauts are shown in Figures SB1.3 and SB1.4.

Figure SB1.2 (a)

The astronauts aboard the International Space Station (ISS) captured this image on July 7, 2020. Their image shows Comet NEOWISE, Venus, Auriga (outlined), the Pleiades (circled), and the foot of Perseus protruding downward from the top.

Image Credit: NASA

(b) I captured this image just before dawn on July 12, 2020, just five days later, from a location near my home in Minnesota. I used a camera and lens similar to the ones used by the astronauts aboard the ISS. Our images are nearly identical! My image also shows Comet NEOWISE, Venus, Auriga (outlined), the Pleiades (circled), and the foot of Perseus protruding downward from the top. Comet NEOWISE’s position has moved, owing to the five-day interval between our respective photographs (see chapter 4 to learn more about comet motion).

So remember that you are already an astronaut on spaceship Earth. All you need to do to explore space is to view the cosmos on the next clear night! And with the help of this book, you will learn how to collect photographic souvenirs from your cosmic travels to treasure and share with your family and friends.

Now let’s prepare for liftoff by learning more about what we can capture with our cameras as we travel together through space!

Figure SB1.3

Comparable views of the Milky Way as seen by Space Shuttle astronauts and earthly astronauts in California on a photo workshop. The Dark Horse Nebula is outlined in each.

Space Shuttle Image Credit: NASA

Figure SB1.4

Comparable views of the constellation Orion from aboard the ISS and Antigua on Earth. Orion’s Belt, Orion’s Sword, and the bright star Sirius are outlined in both.

ISS Image Credit: NASA

2

Understanding the Night Sky

Exploring the night sky and discovering objects to photograph are among the most exciting aspects of astrophotography. This chapter will get you started.

How to Explore the Night Sky

What’s the first thing you do when you plan a vacation? Decide where to go! Then you can choose what to bring and what you might expect to see.

Exploring the night sky with your camera is similar, except you can do it for free and without leaving home. One night you may find yourself wandering down dusty alleyways in the Milky Way, looking to see what you can find hidden inside. Another time you might take a trip through sparkling clouds of stars, basking in the fierce glow of thousands, millions, even billions of fiery nuclear furnaces. Or you might float serenely in the light of vast clouds of luminous gas, watching baby stars being born.

In this chapter, you will learn how to understand and explore the night sky. Your knowledge of these essential astronomy methods will form the foundation of your understanding of astrophotography.

Night Sky Maps

Let’s begin with the familiar Earth globe (Figure 2.1(a)). The map on its surface displays the recognizable contours of the continents, islands, and oceans, along with countries, cities, and other landmarks.

Figure 2.1

(a) The globe of the Earth’s surface shows the terrestrial poles and equator. (b) The celestial sphere represents how the night sky appears as viewed from Earth, seen at its center. Prominent night-sky objects are marked on the celestial sphere. The celestial poles and celestial equator are also shown—extensions of the terrestrial poles shown on the Earth’s surface.

A transparent, sphere-shaped globe of the night sky is the cosmic equivalent (Figure 2.1(b)). This celestial sphere displays the stars, constellations, and other key objects. Although the celestial sphere doesn’t represent the true, three-dimensional nature of how things are distributed throughout the universe, it is still a valuable model for understanding how night-sky objects appear as viewed from Earth.

The celestial sphere and globe move freely with respect to each other. To represent a 24-hour day, you would hold the Earth’s globe in place and rotate the celestial sphere through one complete revolution.

While the globe and the celestial sphere are helpful visualization tools, two-dimensional maps are more practical for your night-sky explorations. For example, look at the familiar map of the Earth’s surface shown in Figure 2.2(a). This map is created by unpeeling the globe’s surface in Figure 2.1(a). Similarly, we can prepare a two-dimensional map of the night sky (Figure 2.2(b)) by slicing open and flattening the celestial sphere (Figure 2.1(b)).

Constellations

The night sky map in Figure 2.2(b) shows the constellations that divide the night sky, just like the world map shows the countries that divide up the surface of the Earth in Figure 2.2(a). Eighty-eight constellations exist in the night sky, each rich in storied mythology.

The constellations and most of their contents remain permanently fixed in the sky. Exceptions include the planets, the moon, comets, and satellites; these objects continuously move from one constellation to the next.

Figure 2.2

(a) World map showing latitude and longitude coordinates; (b) Celestial map showing right ascension (RA) and declination (Dec) coordinates—the cosmic equivalents of latitude and longitude.

Each constellation is also home to one or more fascinating deep-sky objects, such as distant galaxies, gas nebulae, or star clusters. For example, you will always find the Whirlpool Galaxy in the same place in the constellation Canes Venatici (Figure 2.3). Any time you wish to find a new night sky object, start by looking up its host constellation to narrow your search.

Figure 2.3

The Whirlpool Galaxy (M51) is always in the same place in Canes Venatici. (a) Constellation map; (b) Image of M51 and nearby stars.

Navigating the Night Sky

Okay, you have your night sky map—now how do you use it to find a particular object? This is where the two different types of astronomical coordinate systems come in:

Celestial coordinates allow you to locate objects on the night sky map. The celestial coordinates for most objects never change. Exceptions include planets, the moon, comets, satellites, and other moving objects.

Local coordinates allow you to locate objects in the sky at a given time and date relative to your current position. The local coordinates for all objects are constantly changing owing to Earth’s rotation (except for geosynchronous satellites).

This section explains both coordinate systems—what they are, how to use them, and when to use each one.

Celestial Coordinates

Let’s begin with a brief refresher of some basic geography, starting with Earth’s north and south poles. Along with the equator, the poles are key positioning features of the earth’s surface. The earth’s axis