It had been on my photographic bucket list to photograph the Milky Way. The key I believe to a good Milky way photograph is the foreground and the setting in which you take the picture. I knew from my research on how to photograph the milky way that in the northern hemisphere in the springtime it sets in the southeast around 4am. Looking at my foreground options as I planned out the night shoot I knew unfortunately that the location of Mann Lake in relation to the Steen Mountains would not allow me to get a photograph of the milky way setting over them. The lake on the other hand was in perfect position to photograph as a foreground. In the photograph above you can even see some reflection of the brighter stars in the lake.
Here is the Steen Mountain range. It is south and west of Mann Lake.
So what did I learn about night photography? One of the things was how to get a clear focus at infinity. If you rely on the infinity marking on your lens you will usually end up with a blurry picture since most lenses actually focus “beyond” infinity. It is way to dark for phase detection autofocus, because of this if your camera has a live view mode this is what you will want to use.
Step one is to turn on live view and find the brightest star in the sky to center on. Second step is to zoom in to the star. Once you are zoomed in you can then use manual focus to make the star a pin point of light. If the moon is out you can use the moon to obtain a good focus at infinity. This makes focusing much easier since the moon is so much brighter, but if the moon is out even if it is a sliver the increase in ambient light will make photographing the milky way much more difficult.
So how do you set up your camera to take night photography? The first thing you need is a “fast”, meaning a lens with a large aperture, wide-angle prime lens. This large aperture is in the f/1.4 or f /1.8 range. This is very large aperture which makes the lens more able to gather the light of the stars. You can at times get away with a f/2.8 aperture. A quick refresher for the beginners, aperture is the size of the opening through the lens, and determines for the most part how much light can reach the sensor. In “f-stops” as the changes in aperture are called, this allows the camera to take in as much light as possible. So with night photography you want the largest aperture possible. The nomenclature for naming f-stops follows a logarithmic pattern.
So after setting your lens to its largest aperture possible the next step is to change the ISO setting of your camera to a high number somewhere in the 3200 range. You want your sensor to be very sensitive to light. The only downside to doing this is that the higher the ISO setting the more noise is introduced to the image. You’ll see this mose=t apparently in the darkest areas of the photograph. This is where an FX sensor would be nice because they have a much better high ISO performance.
When I took the above picture I was surprised by the redness of the tent. I realized that the propane heater in the corner of the tent was casting a red glow. I took a second shot, actually it took a few shots to get it right…., where I “painted” the tent with my flashlight to light it up white.
So after you have a large aperture with a fast “film” speed of 3200 iso, the next step to determine is the shutter speed. With night photography where you are using long shutter speeds an interesting phenomenon occurs. Shutter speeds over 20-30 seconds show star trails due to earth rotation. This can be a great photograph in and of itself, but when you are trying to photograph the stars themselves realize the longer the shutter speed you use the more the stars will appear to be blurry due to star trail elongation. I found that a shutter speed on the D7000, with a 35mm f1.8g and an ISO of 3200, of 20 or 25 seconds to be the right length.
I actually shortened the shutter on the photograph above to only 6 seconds to highlight the brighter stars. Can you find the Big Dipper?
One of the other obvious pieces of gear is a stable tripod. Not only is it not a possible to hand hold night shots of 20+ seconds, but often when you are photographing at night it is also windy. I prefer a tripod with a ball head because it is easier to adjust and move as the sky changes.
My next goal is to get a shot of the milky way with Mt. Shasta in the background. One of the great Mt. Shasta photographers in the area Mark Stensas has such a shot and it looks amazing.
So get out there and try your hand at night photography and let me know how it goes!