Greetings astrophotographer, in this article, you will learn how to do Milky Way photography. It’s not as hard as it looks.
Get tips on how to choose a location, when to plan to head out, minimum equipment requirements, and how to compose astrophotography scenes that will wow your friends and family.
Also, just for fun, we’ll talk a bit about astrophysics.
Doesn’t that sound cool? Let’s get started.
DEFINITIONS FIRST
Space, the final frontier…
Throughout this article, I will use the following terms, Milky Way and Galactic Center.
What is the difference? The Milky Way is the name of the galaxy we call home. It is visible year-round as long as the night is dark enough.
The Galactic Center refers to the rotational center of the Milky Way. It is the densest and brightest part of the galaxy and the feature most often associated with Milky Way Photography. The Galactic Center is not visible year-round due to the Earth’s orbit around the sun.
With some of the terminology out of the way, it’s time to move into the next step, planning your Milky Way photographs.
PLANNING MILKY WAY PHOTOGRAPHY
If your aim is to capture a photograph of the Galactic Center of the Milky you need to start by understanding some basic planning requirements first.
The components that help make a successful Milky Way photograph include a dark sky, timing, and the right mix of equipment. In other words, you need to answer the questions of where, when, and how.
These questions can be answered in any order, but you need to do so in order to give yourself the highest chance of success with Milky Way photography.
WHERE TO SHOOT
The answer to the question of where should you go to shoot requires a bit of work. However, the answer boils down to anyplace that is dark enough.
Unfortunately, photographing or even seeing the Milky Way in or near a city is quite difficult. This is because when the sun sets, the city lights come on. The glow emanating from them creates a phenomenon known as light pollution.
If you look at the sky in the following photo from Dubai you’ll notice the lack of visible stars in the sky. This is the result of the light pollution generated by the glow of the city lights.
This photo of the Milky Way over Morro Rock (below) lacks the vibrancy of those taken away from the lights of a nearby town.
FINDING DARK SKY
So, if you can’t really see the Galactic Center in a city, where can you go?
Fortunately for you aspiring astrophotographers and those who just like stargazing, there are plenty of good resources to help you find a dark sky.
Online resources
A couple of good places to start your search are Dark Sky Finder or the International Dark-Sky Association.
You can find maps like the one below to help you find dark sky areas to do Milky Way photography.
Mobile Apps
Dark Sky Finder has both Apple and Android friendly apps. It shows a color-coded map to help you navigate to dark skies near you.
It has the same function as the online version but is with you as long as you have cell service, so it is more useful in the field.
Take note of how the severity of light pollution (white/red is the highest level of pollution) around the major cities compares to the low light pollution levels around Yosemite National Park.
This means you are going to have a much easier time photographing the Milky Way in Yosemite than in or around San Francisco.
WHEN CAN YOU SEE THE GALACTIC CENTER
Time of year – Milky Way season
If you are planning your first trip to photograph the Milky Way it’s good to understand some basic parameters.
First, the Galactic Center is visible from roughly March through October, this is referred to as “Milky Way Season” by most astrophotographers.
Time of month – moon phase (drilling down to more specific timing)
The next piece to consider when planning your Milky Way photography adventure is the lunar phase. The best time to shoot is the date of the new moon plus or minus three days. With seven nights per month of opportunity, you are bound to have at least one good night.
To find the moon phase you can Google it, use the Photopills app, a good old fashioned paper calendar, etc.
CLEAR SKIES
This is about refining your timing ever further yet.
The weather is another important consideration for your astrophotography adventures. Simply knowing the date and time you plan to visit a site will not guarantee you can see the stars.
Factoring weather into your plans should not be overlooked. Check out the following resources to help you decide if the weather will be favorable.
- Online: Weather.com (just enter your shooting location)
- The Weather Channel mobile app
EQUIPMENT LIST FOR MIKLY WAY PHOTOGRAPHY
Minimum camera equipment needed for Milky Way photography
In order to give yourself the best chance of capturing the Milky Way, you need at least the following pieces of equipment.
- A camera with good high ISO. You need the ability to capture acceptable images at ISO 1600 or higher.
- A relatively wide lens. I currently use a 12mm Rokinon f/2.0 lens. ***Note: Because my primary camera is a Sony a6000, which has an APS-C sized crop sensor, 12mm has the equivalent of an 18mm field of view for a full-frame sensor. This is important to know in the following step.***
- A wide-angle lens is recommended because you are working with a large section of the sky.
- A tripod is crucial as the steady foundation on which to mount your camera. Any movement during the exposure will ruin your photos.
- Flashlight, headlamp, etc. Ideally, you want a light source that can create red light which is better to work with when it’s dark because it preserves your night vision.
Optional (but nice to have) gear
- A shutter release cable or remote trigger. This allows you to trigger your shutter without touching the camera. Again, this is about minimizing any camera vibration to give yourself the best opportunity to capture your Milky Way photographs.
You can get a wired or a wireless shutter release, just search for “camera shutter release”. Then you have a choice of a simple one with just a button to fire the camera or one that also has advanced features like an intervalometer for things like time-lapse photography or shooting star trails.
If you can afford it, get the latter as you can always use it as a regular trigger. But then you’ll also have the extra capabilities should you decide to expand your photography horizons later.
Whichever you decide to go for, just check to make sure it works with your camera brand and model number. Every camera has a different kind of connection, check the remote specs it should list compatible cameras.
Note: you can also use the camera’s self-timer, but the fewer times you touch the camera the better.
- A phone with Photopills app installed – The Night AR (Augmented Reality) function of this app really helps to refine your composition when you are at your chosen location. See the image below, it literally shows you where the Milky Way will appear at your current location.
- A comfortable camping chair. You will probably be outside for hours. It’s nice to have a comfortable place to sit to watch the night sky.
HOW TO CAPTURE YOUR IMAGINATION
For your best chance of success, arrive at your planned site during the day. This will allow you to get the lay of the land, scout, and compose your scene.
This is the same approach you use for any other landscape photograph.
Next, set up your tripod and securely mount the camera to match your desired composition. Finally, it is time to set up your camera in preparation for a night photographing the Milky Way.
CAMERA SETTINGS – STARTING POINT
With your composition set and the camera mounted securely to the tripod it is time to turn your attention to your camera settings.
The first place I recommend you start is by setting the focus point on the lens.
Set your focus for the largest available aperture because that is the aperture that will gather the most light for your photograph. Focusing the lens in advance allows you to remove one item from your list of concerns after the sun sets and it gets dark.
Your goal is to set a focus point that allows you the best chance of capturing any interesting foreground elements as well as stars and The Milky Way. Working with a wide-angle lens, this usually means setting your focus near infinity (notice I did not say AT infinity).
Set the lens to manual focus, dial it to infinity and then back just a tiny bit. Then either tape the focus ring down or rubber band it in place so it doesn’t move.
The purpose of locking your focus this way is to prevent any human error such as bumping into things at night. It’s a huge disappointment to think you have captured a really great image only to discover that it is not in focus when you load it on your computer afterward.
SHUTTER SPEED
To capture sharp astrophotographs you need to also consider your shutter speed. As we discussed earlier, the Earth is rotating relative to the stars. So if your shutter speed is too slow the stars and Milky Way will be blurry.
So how do you know what shutter speed to use? The answer to this question requires a little math, but don’t worry, the calculation is pretty straight forward.
You are going to use something called The 500 RULE to estimate the maximum shutter speed you can use to keep the stars and Milky Way as sharp as possible.
THE 500 RULE
First, just divide 500 by the focal length of the lens (full-frame equivalent) you plan to use to capture your image. NOTE – if you are using a crop sensor camera I recommend accounting for the equivalent focal length.
What is a full-frame equivalent focal length? That is a function of the difference in size between a full-frame sensor (one that is the same area as a 35mm negative) and a smaller sensor. For my Sony a6000, the size ratio is 1.5:1.
This means that a full-frame sensor is 1.5 times the size (that is the crop factor) of the sensor in my camera. What this means is that even though I am using a 12mm lens, the camera sees the full-frame equivalent of an 18mm one (1.5 x 12mm = 18mm).
Therefore, according to the 500 Rule, if I want to calculate the maximum shutter speed I can use with my 12mm lens, I need to divide 500 by 18. The result is 27.8 seconds.
Keep in mind this number is a rough estimate. Through trial and error, I have found the best result is closer to 20-25 seconds. So start with the number you get and adjust accordingly as needed.
As I said, these are the parameters for my camera. I recommend taking the time to research your camera to determine what size sensor it uses so you can perform the calculations for yourself.
Some common lenses and the 500 rule results (full-frame equivalent in brackets)
- 8mm (12mm equivalent) = 41.66 seconds
- 10mm (15mm equivalent) = 33.33 seconds
- 12mm (18mm equivalent) = 27.8 seconds
- 18mm (27mm equivalent) = 18.5 seconds
Notice that the longer focal length you use, the shorter the exposure that becomes necessary. Any longer than 18mm (27mm full-frame) and you will have a hard time capturing the Milky Way due to field of view and exposure.
For more examples see the following table.
If you are interested in learning more, check out the following article for a discussion of sensor sizes. What Does Having a Crop Sensor Camera Really Mean?
APERTURE
In the equipment section of this article, I mentioned you should choose a lens that has a maximum aperture of at least f/2.8.
Because you are working at night and have limits on the shutter speed you can use (as you learned above with 500 rule), having a lens with a large aperture helps to collect more light. My personal favorite lens has a maximum aperture of f/2.0.
If you don’t currently have a lens with this capability, borrow or rent one first to try out. Borrow Lenses is a site that rents cameras and lenses, as does Adorama out of NYC. If you’re outside the USA try a local camera store.
Then if you find that astrophotography is a passion and you want to do more of it, consider buying a suitable lens.
ISO
The last camera setting is the ISO. I saved this for last because I like to dial in the ideal shutter speed and aperture before setting the ISO.
With many nights photographing the Milky Way under my belt I know that I’m not satisfied with the image quality if I use an ISO greater than 1600. So, if I can achieve good exposure with a lower ISO that is always my preference.
Keep in mind this is with my current camera and lens combination. I recently had the chance to work with the Sony a7rIII and found good results up to ISO 6400. So this is my personal choice based on my own gear.
Image quality is subjective. Only practice will help you decide the right combination for you.
COMPOSITION – ADDING A BIT OF WOW
In astrophotography, you need more in your image than just the Milky Way to make interesting photographs. Be sure to incorporate foreground elements that add to your composition.
This is no different than composing scenes during the day. If you are seeking guidance check out this article on composing landscape photographs.
SUMMARY
All of the tips and suggestions I’ve provided for you here serve as a starting point for your journey into Milky Way photography. The exciting part is just beginning.
Now I’d encourage you to plan on spending some nights beneath the stars exercising your creativity on your future Milky Way photography adventures.
If you get out and get some great Milky Way photos please share them in the comments below. Tell us how you did it and if you have any issues or questions please ask.
Until next time, see you on the trail.
