However, a developer and GIMPer (the term we use to describe subscribers to the Davies Media Design GIMP YouTube channel) named Kevin Thornton created a custom plugin using some coding (he created it using the Python coding language) to allow us GIMP users to perform adding Luminosity Masks to image compositions simply by selecting the command from the Filters Menu. That above paragraph was not designed to actually tell you how this process is completed – just to give you an idea of the complexity of the process. For more information on how Luminosity Masks work and why they are useful, I recommend checking out the tutorial.ĭespite this method being useful and giving you more control over your image, it can be a bit of a time consuming process as it involves duplicating and desaturating your original image, selecting areas of certain luminance in your image and creating custom channels from those areas, and then applying each new custom channel to a new layer mask – which creates 9 duplicated versions of your original image plus 9 layer masks. In other words, you can make image adjustments that will only affect the aforementioned portions of the image – like changing the colors of the lightest parts of the image using the Color Balance tool or increasing the shadows of the darkest parts of an image using the Shadows-Highlights tool. This technique allows you to edit the light, lighter, and lightest parts of an image, the dark, darker, and darkest parts of an image, and the three different levels of mid-tones in an image separately.

In May of this year (2018), Davies Media Design created a tutorial on how to edit photos using a luminosity mask in GIMP 2.10.

Gmask for mac