Scott Kranz
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How to Start Astrophotography

©Scott Kranz Banff Vermilion Lakes Night

I recently had a few friends and family ask me how to do astrophotography – that is, how to photograph the stars visibly in the night sky. Although I’m no expert, I was able to share what I know, give a few suggestions of settings to use, and help them capture their first star shots.

It wasn’t too long ago I was in their shoes asking a knowledgeable friend how to do the same (only about one and a half years ago in fact). If you are similarly curious about night photography and want to give it a try, check out some basic pointers below to get started.

Know your gear

Do you have the right camera? Familiarize yourself with your camera. Does it have the basic functionality needed for a good night shot? Check to see if you can manually adjust shutter speed, aperture, and ISO (each addressed below). Remember you don’t need an expensive camera or a DSLR to capture stars. I’ve captured stars with a DSLR (a Canon 5D Mark III) and even a point and shoot (a Sony RX100 III). You just need a sufficiently powerful camera with the basic functionality for astrophotography, and the rest is execution. 

Do you have a worthy tripod? In addition to the right camera, you’ll need stability, most commonly in the form of a tripod. Unlike daytime photographs, which are often a quick fraction of a second in shutter speed, nighttime photographs can be upwards to 30 seconds in length. Have a tripod that is plenty sturdy, given the weight of your camera and any external forces (such as the wind). I currently use a MeFOTO Globetrotter Carbon Fiber tripod.

Find the best environment

If the stars are what you’re after, you’ll need to get away from most artificial light pollution (from cities and large towns). Head into the wilderness where the stars shine brighter. If you already plan on hiking, backpacking, skiing, etc., in the backcountry, you should be set, assuming the weather offers fully or partially clear skies.

A night near Washington Pass, with little to no artificial light pollution present, involved a surprise appearance of the Aurora, an awesome experience. Settings: 25 secs, f/2.8, ISO 2500.

A night near Washington Pass, with little to no artificial light pollution present, involved a surprise appearance of the Aurora, an awesome experience. Settings: 25 secs, f/2.8, ISO 2500.

Dial in the right settings

Focus first. When starting astrophotography, a worthy goal is to vividly capture tack-sharp stars. To do so, you need to set your camera lens to manual focus or “MF” (as opposed to auto focus or "AF"). Then, manually focus “on infinity.” Often lenses have an infinity marking (the symbol ∞) to dial to.

In addition to focusing on infinity, you need to nail down shutter speed, aperture, and ISO.

  • Shutter Speed: To capture the dim starlight in the night sky, your shutter speed for a night shot will be significantly longer than daytime shots. Night shots can be 10 seconds, 20 seconds, or even 30 seconds in exposure length. Also, know the moon’s current phase, brightness, and positioning in the night’s sky. If there is little to no moon light (and little to no light pollution), try a 20 or 30 second exposure, for starters.
  • Aperture: Your camera’s aperture, the “F-number,” concerns the size of the shutter’s opening, which impacts the amount of light and depth of field. Remember that measuring aperture by “F-number” is somewhat backwards: the larger or wider the aperture, the smaller the “F-number.” In general, you’ll want to set as low of an “F-number” as possible (f/2.8 or lower is ideal) to let in the most starlight.
  • ISO: ISO concerns your camera sensor’s sensitivity to light. The higher the ISO, the more light it will capture. But there’s a caveat: when you increase the ISO, you increase the amount of grain or “noise” in the resulting photo, which, in turn, degrades the sharpness and quality of the image. For starters, I’d recommend anywhere between 2000 to 4000 ISO depending on your camera and the amount of moonlight and artificial light you can see.
With plenty of light pollution on the horizon, I went with a somewhat quicker shutter speed for this night shot in the North Cascades. Settings: 15.0 sec, f/2.8, ISO 4000.

With plenty of light pollution on the horizon, I went with a somewhat quicker shutter speed for this night shot in the North Cascades. Settings: 15.0 sec, f/2.8, ISO 4000.

Without any light pollution on the horizon above Mount Shuksan, I slowed my shutter speed down all the way to 30 seconds. Settings: 30.0 sec, f/2.8, ISO 4000.

Without any light pollution on the horizon above Mount Shuksan, I slowed my shutter speed down all the way to 30 seconds. Settings: 30.0 sec, f/2.8, ISO 4000.

Trial and error

After you test out your initial settings, check out the resulting image for focus and lighting. Are your stars tack sharp? If not, double check your focus and even play around with small incremental turns next to the camera’s infinity marking to try to find the camera’s true infinity focus. Is the photo too dark or too light? If it’s too dark, try slowing down the shutter speed further or increasing the ISO. If it’s too light, try the opposite.

Experiment and have fun

Once you meet the goal of capturing tack-sharp stars, get creative with artificial light in the foreground. Use a headlamp, a flashlight, or lantern.  Overall, get creative, have fun, and enjoy the great outdoors in the beautiful dark of night.

A popular subject to use when backpacking is your tent. Use of a dim headlamp or other artificial light can give the tent a warm glow to your shot. Settings: 30 secs, f/2.8, ISO3200.

A popular subject to use when backpacking is your tent. Use of a dim headlamp or other artificial light can give the tent a warm glow to your shot. Settings: 30 secs, f/2.8, ISO3200.

 

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I hope you found this quick beginner’s guide to astrophotography helpful. If you try out these tips in the field, I’d love to hear how they worked (or didn’t), and I’d love to hear any follow-up questions you might have below in the comments.

This year I will be offering private photography lessons, post-production workshops, and portfolio reviews. If you have any interest, please reach out to me here for more details.

Cheers! 

-Scott