An Introduction to Landscape Astrophotography (Capturing the Milky Way, Planets and more)

Landscape photography of the night sky is the most straightforward type of astrophotography. In this article I am going to explain how to get started in it.

In recent years, advances in mobile phone technology have made astrophotography increasingly accessible to the amateur.

An example of landscape astrophotography would be to take wide angle pictures of targets such as the Milky Way galaxy, the Andromeda galaxy, planetary alignments, constellations, etc.

To do landscape astrophotography your camera needs two essential components. It must be possible to set an exposure length of at least ten seconds. This is how long the camera's shutter will be open absorbing information. A longer exposure will increase the detail and brightness of the image.

The second ability that is required is being able to change the ISO of the exposure. This is how strongly the camera responds to light. In addition to increasing the brightness of the image, a higher setting will also increase the noise. A good setting for landscape photography is between 1800 to 3200. This will involve a bit of trial and error with your camera to ensure you are not introducing too much noise.

In cameras where you can select the lens, such as a DSLR, you want an aperture of F2.8 or less to let in as much light as possible.

Another important feature is manual mode. Using manual focus allows you to focus on stars rather than relying on the camera to do so, which is important since autofocus does not always work with stars. 

When focusing, try to focus the stars so they are as small as possible.

So, when you have your camera, it is a good idea to mount it on a basic but stable tripod. This will allow you to point the camera in the direction you want. Of course, for a mobile phone you will need an adaptor to make this possible.

Based on what you have read so far, you may assume that the ISO and exposure should be set to the highest setting. Unfortunately, this will result in star trails. As the stars move in the night sky it will cause corresponding trails in your image.

A good rule of thumb is to divide 400 by the focal length of the camera's lens, note this used to be 500 but with the ever-increasing camera sensor sensitivity has dropped to 400.

Once you have taken a photo check to ensure the stars are still points by zooming into a single star. If they are appearing as small lines still then you need to reduce the exposure.

One obvious way around this issue is to use an expensive star tracker to move the camera coordinated with the stars. However as this is only an introduction to astrophotography a cheaper alternative is to take the longest possible exposures without creating star trails and then combine each individual image together to create a combined image with greater detail and a longer total exposure.

If you want to capture the milky way, point south in the northern hemisphere and directly overhead in the southern hemisphere. The best time of year to capture the milky way is from mid-march to mid-October. If there is too much light pollution, sometimes the Milky Way will appear in your photos but not visually.

The approach I lay out here makes post-processing on the computer easier for most people.

The first step is to use Sequator. This simplifies this process greatly and makes it easy to produce great results. Start by loading all your images into Sequator, by double clicking on the Star Images option on the left-hand side.

You can also create noise images by using the same ISO and exposure length as the main images, but with your lens cap on. This can then be added on the Noise option and will help remove noise from the final image.

Then select an output image to save the result to. I would choose the TIFF file format as it keeps a lot of the detail and can be easily edited in GIMP, which is downloadable for free.

Next choose the composition from the options in the bottom left of the screen. Here you want to align the stars as we are trying to produce a landscape image.

If you have ground features in your image, I would suggest that you use the Freeze Ground option. Then select the Sky Region option and then choose an irregular mask and paint the parts of the image that is the actual sky.

I usually turn on Auto Brightness especially if there are a lot of images as this will stop the image becoming over exposed.

I also turn on Reduce Distortion Effects, Remove Dynamic Noises and Reduce Light Pollution. But you can always do a bit of trial and error here.

Then press Start to start the stacking. Once the image is complete, open the image in a photo editing application like GIMP. And go to the levels. Here you want to move the extremities of the levels closer to the actual data being careful not to wash it out. I also usually move the black point after I have done to perfect the image.

To see a walk through of all the equipment you need and how to use Sequator please watch the episode below.

I get commissions for purchases made through affiliate links in this article.


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