Learning to photograph the Milky Way might seem overwhelming. Many terms and alot of equipment can be discussed - causing confusion. As you learn more, you become aware of other tools and techniques that can aid in making a great image. There is definitely a learning path to night photography and I plan on creating an infographic to help explain that - but for now let start at the beginning, here I will explain how to simply photograph the Milky Way. There are 5 things you need to know:
When to photograph?
Where to photograph?
What is equipment is required?
What are the camera settings?
The image above is just a simple image of the Milky Way high in the summer night sky. No other technique was done to capture this image such as lighting the foreground.
When to photograph? There are a few parts to this question.
Milky Way Season: Note that since we are located in the Milky Way galaxy, anytime we look up in the night sky, everything we see is technically the Milky Way. However, what do we mean by a "Milky Way season?" In the Northern Hemisphere, the middle of our galaxy, with the dense, colorful nebulas and a multitude of stars, is above the horizon at night between March and October (the core is above the horizon in the daytime the remaining months of the year). We call this the Milky Way season. However, even in the winter months, you can still see the Milky Way, just not the dense, colorful "core." The picture below shows the winter night sky during the Geminid Meteor Shower.
No or Little Moon: The second part is to work around the moon. Any moon (or any bright light in the area) greater than 6% will obscure the Milky Way in your image. It's almost impossible to get the Milky Way and that bright light in one image. So, get to know your moon cycles. If you are planning a trip to photograph the Milky Way, you will want to photograph when there is little to no moon in the sky.
You don't always need a new moon. Depending on the time of year, you can work around a moon rise or a moon set. In the beginning of Milky Way season, the core doesn't rise above the horizon until the early morning hours of the night. As Milky Way season gets further into the year, the Milky Way core rises earlier to the point where the core starts to set below the horizon during the night.
For example, if it's early in the Milky Way season (like March) and you know the moon sets at 1:30 am, you can still capture the core of the Milky Way which may not rise till 2:00 am (even though it's not a new moon). Is there an easy way for figure all this out? Yes! I am a big fan of PhotoPills app and use it for all my night photography planning.
Needless to day, you need clear skies. Make sure to check the weather too! There are several websites that are fairly accurate with providing cloud cover information 24 hours ahead of time.
Where to photograph?
Dark Skies: There are several websites that can show you, on a scale, where you can find dark skies, with little to no light pollution.
The light pollution map shows in color codes, the Bortle scale for the skies. The Bortle scale is a nine-level numeric scale that measures the night sky's brightness of a particular location. The darkest skies are the darker area on the map.
What's the difference? Check out the two pictures below.
This picture taken from Big Bend National Park, Bortle Class 1, some of the darkest skies in the US with no major light in the direction we are shooting (south).
This picture was taken near Caprock Canyon State Park, Bortle Class 2 skies, light pollution from nearby cities on the horizon in the direction of the camera.
The darker the skies, the better the Milky Way will pop!
What equipment is required?
There are at three critical pieces of equipment that are absolutely necessary. Now, I would absolutely recommend more equipment if you are going out (like lights, chair, etc), but let's just focus on this one simple image.
A camera (with memory card of course) that can be placed into full manual mode: Almost any of the newer cameras will work (both DSLR and mirrorless). Without going into great detail, the most important thing is that you need a camera where you can place it into full manual mode that allows you to manipulate ISO, shutter speed, and aperture independently of each other (not all cameras will do this). The camera you choose must be able to work well in low light conditions. Newer cameras have better technology (better sensors) and do a better job at this task. However, not everyone can go out and buy the latest cameras.
A (fast) wide-angle lens with at least 2.8 aperture (or more...such as 2.0, 1.8, or even 1.4) This is critical. Don't plan a trip and spend money to get there (flight, hotel, etc) without the right lens. A lens with aperture of 3.5 will be very different image from what you get with an aperture of 2.8. The bigger the aperture range, the more expensive the lens. Many folks starting out in night photography do not have these lenses. I highly recommend that you rent one. There are several companies that allow you to rent a lens. It's easy and they will ship it right to you! I have used them! Super efficient! The lenses were great.
A tripod: If you already own a tripod, then great! If you are going to buy one, I recommend a sturdy tripod. When I first started getting into night photography, I figured a tripod was a tripod, not paying attention to any of the advice of more experienced photographers to put some money into the purchase a tripod. If you like landscape and/or night photography at all, a sturdy tripod will go a long ways. Here is where I say, "Buy it right the first time!" All it takes is a little wind to ruin a great picture taken on a cheap tripod. Another thing to consider is the weight of the tripod. Lighter carbon tripods, which are very sturdy, cost more but are easier to transport when hiking into a photo spot.
What are the camera settings?
While there are many different settings for different types of night photography, let's just focus on getting a simple Milky Way photo.
Keep in mind, camera settings are relative. Meaning, everyone's camera and lens are different - so one simple set of settings will not work for everyone. In addition, the amount of ambient light in the atmosphere also can make a different to what settings you choose.
Let's review some basic settings that you can start with and then just adjust as needed:
Aperture: f/2.8 or wider
Have your aperture as wide open as your lens allows. This is what allows all the light to hit your sensor. The bigger the pin hole, the more light you will capture. There are other types of night photography images where a higher aperture is recommended, but not for the basic Milky Way picture.
Shutter Speed: Let me answer this in two ways....
Don't care about star trails? Then set your camera to 30 seconds.
Want pinpoint stars (without any lines from the stars making star trails)? Then shutter speed is critical to get right. Even though the longer the aperture is open, the more light you get on your camera's sensor. If you don't want start trails, you are limited by your lens' focal length. There's a formula that you can use to figure out your shutter speed, " the 500 Rule":
Shutter speed (seconds) = 5oo / focal length (mm)
For example, if I am using a lens at a 16 mm focal length, I don't want have my shutter speed longer than 31 seconds or I may see star trails.
500 / 16 mm = 31.25 seconds
Some photographers, use the 400 rule ( a bit more strict with shorter times). However, if you are just starting out, the 500 rule is adequate. What's more important is to zoom into your image (from the camera view finder) and inspect it for star trails. If you see them, adjust your shutter speed, and retake.
ISO: ISO is usually the last setting we adjust. In general, start out at ISO 1000 and adjust from there. You can increase ISO, but be aware that some cameras have better ISO tolerance than others.
On my Canon 6D, I can only push ISO up to about 2500 with minimal noise. On my Sony A7R3, I can push ISO up to 6400 with minimal noise.
Cameras that do not have a high ISO tolerance, show "noise" on the image at high ISO settings.
White Balance: The color of your sky and Milky Way are very subjective. Some folks like warmer skies than others. While you can always edit in post -processing, I recommend that you take your white balance settings off of automatic white balance (AWB). Otherwise, your camera will decide what to color the sky - and this could change between every picture!
My "go to" White Balance Setting is 3800 Kelvin. I tend to like more bluish Milky Way skies and 3800 gets me where I like to be.....again, this can be changed in post-processing.
Focus: Manual - Absolutely place your camera in Manual Focus. Which leads to the next question, How do you focus at night? I will address this in a different blog post. You can view it here.
Final point, since every camera is different, always check your images to adjust settings. Do this by reviewing the image on the back of you camera 's LCD screen and use the magnifying glass icon to zoom into the picture.
Too much noise in the image, bring down your ISO to a lower number.
Star trails? Increase your shutter speed (less time).