How To Photograph Star Trails

STAR TRAILS PHOTOGRAPHY and settings

Learning to take photos of star trails is not as hard as you may think. Here I’ll tell you how to take star trail photo and the settings I use step by step.

 

Squamish Dirt Road Nikon D750 and Nikkor 20mm f1.8 Bortle Class 4

BASIC EQUIPMENT

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Camera with Manual mode – M on the dial so will need to be able to set the ISO and Aperture

Intervalometer – So you have have the shutter open longer than 30 seconds

Wide Angle Lens – A lens that can be set to Manual focus. I would say nothing over 35mm. A fast lens but not over f4 or faster e.g f2.8, f1.8. The smaller the number the more light that is let through to the camera

Tripod – a good sturdy tripod so there is no movement

Photo editing software – Photoshop or something like Gimp which is free

Here is a link to the gear I use My Gear List

Star Trail Settings

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• Ideally you need a dark night sky no more than class 4 on the Bortle scale. I personally use light pollution map to plan where I’m going to take my astro landscape photos.
• After setting up your gear you will have to focus on the foreground interest. Your foreground interest will be at a distance where focusing at Infinity (∞) will have the foreground in focus.
• To focus at Infinity (∞) use the camera live view e.g. using the screen on the back of the camera. Find a bright star in the sky and with the + button/screen magnifier zoom in as much as you can. Once you have the star in the screen focus the lens until the star becomes round.
• Just to note, there is a good chance that the Infinity symbol (∞) wont line up with the make on the lens. Don’t worry about it, it happens on some lenses.
• ISO and Aperture, if you are in a dark area with no light pollution then f2.8 and ISO between 1600 – 3200. If you re in Urban with light pollution or with partial moon then stop down a little to f5.6 and ISO to 800.
  I normally take a couple of test shots and move my ISO up or down to get the best results.

  There are two ways of getting star trails

  1. Using the 500 rule PhotoPills Calculator set your shutter speed so there are no star movement. With the intervalometer take a minimum of 60 photos to get some star trails, but leaving your camera to take photos for a couple of hours is best.
     This way you can use you images as a single photo of the night sky or make all the photos into a timelapse.
  2. A second way is to set your intervalometer to have your shutter open for 3 minutes for 10 or more photos. Something to note, this way can course Hot Pixels in your image which are individual pixels that look brighter than the rest of the image. Also Thermal Noise can happen the longer you keep the shutter open as this courses the sensor heats up. Saying that 3 minutes seems to be a good amount of time for this not to happen.

  If I’m only looking to do star trails I’ll do the second way as you have less photos to import into Photoshop but there is the risks.

  PHOTO EDITING

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  Photo editing can be more complicated and time consuming than actually taking the photos.

  My personal work flow for star trails is to import the photos into Lightroom. Edit one image and then sync settings. Sync settings copies the settings from the first image and updated all the other images.

  As for what to change on the edit such as exposure, highlights, shadows etc is personal preference, but one thing should be done is Lens Correction.  Lens Correction fixes such lens problems as distortion, chromatic aberration, vignetting and perspective correction.

  I then select all the images and right click and select Edit In > Open as Layers in Photoshop.

  Select all the layers and from the drop down Lighten and at this point the star trails appear.

  From the top menu select Layers > Flatten Image

  Once the image has been flattened into one layer make any changes such as remove spots or lights.

  In File click Save which then save and open the image in Lightroom for any more editing needed.

  End Result

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