Colors AlTaglio 1.0 released →

<> Posted on December 4, 2015 in AppsGamut masking

I'm happy to announce that WheelMasks now has a sister app, Colors AlTaglio, the iOS Photos extension that lets you change the colors of your photos using gamut masking. Since it works with the HUSL colorspace it can modify the hues of an image without altering its perceptual lightness, thus preserving the original tonal range. It's the first photo processing app that works with this colorspace and the first one that lets you apply a gamut mask to a photo.


  • Change the colors of your photos using gamut masks.
  • Preserve the contrast and tonal range of your images after every edit.
  • Set the neutral color of the gamut mask.
  • Change the hues of an image by rotating the color wheel.
  • Immediately preview your changes thanks to the filter being implemented in Metal.
  • Colors AlTaglio is an iOS Photos extension so it's easy to add to your workflows.

Transform the colors of your photos with Gamut Masking, a technique previously used only by painters. Colors AlTaglio respects the perceptual lightness of each pixel between edits. Start your transformations from several predefined masks. Changes to the gamut mask show instantly thanks to the filter being implemented in Metal. Rotate the color wheel for crazy colors of for a subtle temperature change.


Version 1.0.5 →

<> Posted on November 12, 2015 in Wheelmasks

WheelMasks version 1.0.5 has been released on the App Store!

This release celebrates the launch of Procreate 3 by adding an option that allows exporting all the swatches at once to Procreate when there are more than 30 of them. They will be split in palettes of 30 colors once in Procreate but you won't have to export them one by one as before.

I've kept the option to export them individually because sometimes Procreate crashes when opening multiple palettes at once. From my experience this happens when it's displaying an image, but I've had no problem exporting them when Procreate is in the gallery mode.


Wheelmasks 1.0.3 →

<> Posted on October 7, 2015 in Wheelmasks

WheelMasks 1.0.3 is available on the App Store with lots of iOS 9 enhancements!

  • Improves the interface so it works better with the new iOS 9 iPad's split-screen multitasking.
  • In iOS 9, URLs are opened with the new Safari view without leaving the app.
  • Fixes some display issues that appeared with iOS 9.
  • Displays the color values in a modal view on an iPad.
  • Fixes a bug that occurred when exporting more than one time to a Procreate or an Adobe Swatch Exchange palette. The first palette would keep being exported regardless of any changes to the mask.
  • Fixes two crashing bugs.

Do you find WheelMasks useful? Consider writing an App Store review!


Gamut Visualizer

<> Posted on June 2, 2015 in Gamut visualizerTools

One thing that I thought about adding to WheelMasks was a gamut visualizer that could analyze images in the device's photo library. However, I decided not to do it, at least for the time being, to avoid making the app more complex.

I do still think a gamut viewer is a useful tool that lets you see how other artists work with color or just to analyze your own images. There are already a number of gamut visualizers available, but none of the ones I know of have any visual representation of the frequency in which a color is used, so I wrote my own. You can find it below.

If you drag any image file into the box an script will calculate and display its gamut on the color wheel. Everything is done in your browser so the image isn't uploaded anywhere. The difference with other gamut visualizers is that the colors that are less used will be more transparent than the ones that are more frequently used. This allows you to have more information about color usage and helps you determine which zones of the color wheel have been used more in the image.

The colors displayed on the color wheel have only two components from the HSB color model, hue and saturation, and the third component, brightness, is always 100%. This means that any color on the wheel can really appear with different brightness settings in the image.



Rotating the color wheel

<> Posted on May 25, 2015 in WheelmasksTips & tricks

When you're working with a palette with very few hues you may find that the default ones aren't the ones you want. You can rotate the wheel from the Settings screen with a rotation gesture to offset the hues.

For instance, in the following video, starting from a default Red-Yellow-Blue wheel with six hues I've rotated the wheel about 30°. This gives you another six color wheel with a different set of hues that can be useful to create a more original color scheme.

Double tapping on the color wheel, also from the Settings screen, will change the wheel back to the default hues.


Palette Rotation

<> Posted on May 24, 2015 in WheelmasksTips & tricks

The palette view under the color wheel is really just another way to look at the selected wheel colors. Each column is a different hue and the rows show the different levels of saturation, or in some cases brightness, for that hue.

By default it starts at the lowest hue (>= 0°) and ends at the hue with the largest angle (< 360°). That can be a problem when the masked colors are around the 0° hue, on the red and violet zone, because that will cause the palette to be split with a cluster of hues at the start of the table and another one at the end.

In order solve this I've included a way to rotate the palette. Just pan it to the right or left and the colors will move according, allowing you to look at them grouped together. If you want to return to the default palette position a double tap on it will do it.


Using WheelMasks with Procreate

<> Posted on May 22, 2015 in WheelmasksProcreate

Procreate is a great painting app for the iPad, and its swatches file format is one of the formats supported by WheelMasks. In this post I'll explain how WheelMasks and Procreate can work together showing how I used a wheel mask for this portrait.

First, I created my gamut mask, choosing an atmospheric triad with red, green and cyan as my subjective primary colors.

Then, you can send your palette to Procreate. Since Procreate's palettes can have at most 30 colors if your selection is larger than that it will split it in groups of 30 swatches or less before sending them to Procreate.

If you're curious, here are the two palettes in Procreate's format:

I personally prefer to work directly with the color wheel, so I just pasted it on Procreate. I also prefer to have more colors to choose from so before I did that I increased the number of hues and levels to the max.

In this screenshot you can see how I've placed the wheel mask as the top layer and I how colored the background with the neutral color for this color scheme (that's the color in the center of the mask). Here the painting is already finished and the background layer is mostly covered, but starting from a base color helps me paint the rest of the painting.

I keep moving the mask layer around depending on what I'm painting but all the time it's the top layer, by the end of the painting as I tend to pick colors already in the painting I usually hide it.

I only pick colors inside the mask, or from the swatches table, but I tweak them afterwards because you don't need to use the exact color you pick. A mask should be seen as a guide, not as a strict rule. However, I try not to change it to a more saturated color, that could produce an out of gamut color.

For instance, I picked the following orange, but when I tweaked it tried never to cross the red line to the right so as not to get a more saturated hue which would be outside my mask.

In the following posts I'll share more examples with other apps and a more detailed tutorial of how to use gamut masking.


WheelMasks 1.0 has been released on the App Store!

<> Posted on May 18, 2015 in Wheelmasks

As of now, WheelMasks: Harmonic Colors, the iOS app that helps you improve the color schemes of your paintings, is being released on the App Store. If you don't see it yet, check back in a couple of hours, it hasn't spread to your timezone yet.

Remember, it's free with some limits and a one time purchase unlocks all the functionality.

Go get it and let me know what you think!

WheelMasks app icon

Download on the App Store


There's a WheelMasks app preview video now

<> Posted on May 14, 2015 in WheelmasksVideo

Here's a preview video for WheelMasks that I've just released on youtube. The soundtrack is the song "Invasores - First Day" from "Songs for a Brief Evening" by the scarily talented Alejandro Moreno, make sure to listen to his album.


What's Gamut Masking, anyway?

<> Posted on May 11, 2015 in Gamut maskingHelp

Gamut masking is a technique to limit the range of colors available for a painting, in doing so, it's easier to achieve an harmonious painting or illustration. The idea comes from James Gurney who explains it really well in his fantastic book Color and Light.

The gist of it is that you place a shape, usually a triangle, diamond or rectangle, over the color wheel so that it masks the colors you don't want to use and allows you to work with the ones you want. Moving this mask around or transforming it in any way allows you to create and discover new color schemes.

These gamut masks, or wheel masks as they're called in the app, feel sufficient as a color scheme. The gamut they define, that is, the range of possible colors available for a given work, contains subjective primary and neutral colors that make a complete and harmonic color scheme.

They're also very useful for creating color scripts in sequential art forms, such as comics or storyboards, allowing you to come out with diferent color schemes that will make the transition from scene to scene much clearer.

For example, I've painted the following drawing using two different wheel masks as reference:

  • For the first one I used a complementary color scheme with a saturated blue and yellow while every other hue is quite unsaturated. In this mask, there are four subjective primary colors, the blue and yellow mentioned before, and a desaturated red as well as a desaturated yellow. The neutral color is just grey because the mask is centered on the wheel.

    The complementary colors for this gamut mask are all unsaturated. As in all color wheels they're the colors found between the primary colors, in this case they're orange, pale green, cyan and purple.

    WheelMasks Color Demo

  • On the other hand, for the second one I used a triadic color scheme with saturated orange, turquoise and purple acting as primary colors. The complementary colors are less saturated red, green and blue, and the neutral color is also grey because this mask is centered on the color wheel too.

    WheelMasks Color Demo

Although I didn't particularly try to use similar colors for the salamander-like beast on either version, I actually used similar hues to paint the background. It's easy to compare them and notice that the first version is way less saturated than the second one. Yet, there's no problem in separating the greens from the cyans in either of those images because the maximum saturation of each hue is kept relative to the saturation of it's neighbors in each mask.


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