Removing Coma Aberration in Adobe Photoshop: Astrophotography Tutorial

In this video tutorial, Tyler Sichelski walks through a novel method for removing coma aberration from astrophotography using Adobe Photoshop.


We’re always on the look out for lenses that have low levels of aberration (read about the different types of aberration in our practical guide to lens aberrations). But sometimes it’s impractical to just ditch your current gear and upgrade to something that’s only slightly sharper. Tyler Sichelski put together a short and simple video tutorial of how he uses Adobe Photoshop to remove coma aberration from the stars in his astrophotography.
Check out the video below:

If you’d like to follow along with Tyler in the tutorial, he has shared his unedited full resolution photograph with us. Download the full resolution 8.6MB jpeg here.

Before and After

Tyler used his Canon EOS 6D and Tokina 16-28mm f/2.8 lens to shoot this photograph of the Galactic Center rising above the rocks of Sedona, Arizona. The Tokina 16-28mm f/2.8 lens is a great choice for an affordable ultra wide angle full-frame lens but it’s not absolutely perfect when shooting at f/2.8 and shows some mild coma and astigmatism in the corners of the image. Check out this before and after to see how Tyler’s method reduces the apparent aberration in the image and gives the stars a slightly sharper look:


Coma aberration can be a bothersome element in astrophotography. It distorts the shape of the stars and that can distract from the desired look of the final image. Tyler’s simple method is like a “blemish” removal technique for astrophotos that improves the apparent sharpness of the image.

The most beneficial aspect of Tyler’s coma aberration removal technique is that it allows us to continue to use our lenses at their lowest f/number, in spite of what aberrations might start to show up. The lower the f/number, the more light the camera can collect and the “cleaner” the image will typically appear but lenses usually have show worse aberration performance at the lowest f/numbers. Having the option to correct for apparent aberrations in post processing ends up becoming a useful tool for the times when we prefer to use a lower f/number at the expense of aberrations.



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10 Replies to “Removing Coma Aberration in Adobe Photoshop: Astrophotography Tutorial”

  1. You guys are simply brilliant! Useful insights, professionally presented, perfectly paced… I am appreciating all you are doing here and it has greatly helped my images.

  2. Thanks for the info. I am new at astrophotography. and this is great. My son is getting a new Canon for x-mas, and we are learning together!
    Thank you Ian.

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