Infinity color mask magic

As I was adding infinity color masks to the TK7 panel, Sean Bagshaw was busy recording his Sean’s Favorite Photoshop Techniques, Volume 2 series. The download folder for that series contains lots of good color images, and I experimented with some to make sure the new infinity color masks offered something useful and unique for other people’s images, not just my own. They do, and I sent some quick edits to Sean to show him how I’d used the masks on his images.

Sean took these tests and incorporated them into the Quick Tip video below. And, not surprisingly, he’s gone well beyond my own attempts at using the masks and came up with some innovative ways to take infinity color masks to the next level.

This video is a little longer than the other Quick Tips, but it moves fast. Sean covers the basics of using infinity color masks and then demonstrates using them on six different images. Here are some things to pay close attention to as you watch the video:

  • Try to choose a color that actually has some decent color. Remember, these are color-based masks, and if you choose a weak color (low saturation), you’ll get a weak (dark) mask. When creating an infinity color mask, the Color Picker eyedropper extracts the hue value of the selected pixels to build the mask around. The saturation levels of that hue in the image then determines the brightness of the mask. This means that low-saturated colors will still be dark in the mask. So, as much as possible, click on colorful colors to make the best and brightest masks.
  • The initial mask preview is extremely accurate, but modification can sometimes create an even better mask. One of the great features with for infinity color masks is that you get to choose the color from the image and the mask is built around that selection. As such, the original mask preview is always on target, and in several of his examples, where this initial mask is essentially perfect, Sean just uses it as is to adjust the image. At other times, though, he first experiments with adjusting the color range or modifying the mask using the tools in the MODIFY section of the RapidMask module. MODIFY is especially helpful for darker masks where a less-saturated color was the target for generating the infinity color mask preview. The key to success in all cases is to start with a mask properly focused on a specific color selected from the image. And since this is the core process for generating an infinity color mask, the initial mask is always a great starting point. Once it’s available, there are lots of opportunities to customize the mask depending on what you’d like to do to your image.
  • Infinity color masks aren’t just for color adjustments. One of the things that really comes through in watching Sean work on these images is the variety of different techniques he employs. Infinity color masks are used to adjust color, saturation, brightness, and contrast. And he uses them with Curves, Levels, Hue/Saturation, Brightness/Contrast, and Solid Color adjustment layers to achieve the desired effect. This illustrates a good point, I think. To really get the most out of these infinity “color” masks it’s necessary to let go of the “color” concept and simply start seeing them as new precision masks for making targeted adjustments. Just like luminosity masks can be used to make adjustments other than brightness, infinity color masks aren’t restricted to adjusting color. When you start seeing these different types of pixel-based masks as a continuum of masking possibilities, the full power of what they can do really starts to take shape.

If you have Sean’s Favorite Photoshop Techniques, Volume 2 video series, you might want to go into the practice images folder and follow along with what he’s doing here. Working along with Sean will help you see where and how you might be able to apply infinity color masks to your own images.

Finally, just a quick reminder that everything on my website’s Panels & Videos page, including the TK7 panel with infinity color masks and Sean’s Favorite Photoshop Techniques, Volume 2, is 20% off through the month of September with the following discount code: Update20

Be sure to subscribe to Sean’s YouTube channel for more great tips on photography and post-processing including those listed below.
Infinity color masks
Linked vs. unlinked smart objects
Three ways to use Levels and Curves
Reusing saved luminosity masks
Developing a quality night sky
Split toning
Cloud sculpting
Exposure blending
Favorite new V6 features

TK7 Update: Infinity color masks and more

I’m happy to announce that the first update to the TK7 panel has just been released. If you already have TK7, check your email for a free download link. It was sent to the email address you used when purchasing. Be sure to check the spam/junk folder as in many cases it ends up there. Also, be sure to add the download server as a contact. That will insure you get these updates in your inbox. The download server’s address is: client@e-junkie.com

This is a really exciting update. It adds two new mask options to the RapidMask module: infinity color masks and “My Channels” masks. Infinity color masks are a huge step forward. They offer a novel way to generate masks based on ANY color found in the image. You’re no longer limited to Photoshop’s Color Range command (bad blending edges) or color sliders (R,G,B,C,M,Y) for making a color mask. You can now select a color directly from the image and the infinity color mask is constructed precisely around that selected hue. Pixel-based hue values are the foundation for these masks, and hue opens up an entirely new dimension for creating masks. It’s all 16-bit and it’s all pixel-based, so the blending through these new masks is awesome. Infinity color masks are essentially a Magic Wand tool for color. You’ll be amazed at what they can do.

The new “My Channels” option allows you to bring your own masks and selections into the Rapid Mask process. This means that user-generated masks can be easily combined with the module’s native luminosity, channel, color, and saturation masks to better target specific elements in the image. So the Rapid Mask engine can now be powered by ANY mask. There are no limits anymore. With “My Channels” every mask and selection is a Rapid Mask.

Infinity color masks and “My Channels” masks offer a significant expansion of the already considerable masking capability of the RapidMask module. There are also some minor updates in a couple of other RapidMask functions. The video below reviews everything in detail.

If you don’t have the TK7 panel yet, you can use the following discount code for 20% off the updated version and anything else on the Panels & Videos page through the end of September: Update20

Infinity color masks are the most significant new feature in this update and possibly best thing to happen to masking since I pioneered the now ubiquitous luminosity mask techniques in 2006. Luminosity masks are excellent if you’re trying to create selections based on pixel brightness, but not so good if your primary selection criterion is color. Completely different colors can have the same level of brightness, and luminosity masks can’t differentiate between them. Adobe’s Color Range command can be used as an alternative to select specific colors (and it’s the basis for the single-color selections in the RapidMask module), but the edges of Color Range selections aren’t very good. I frequently find it hard to get good blending using standard Color Range selections in many situations. That’s why I added the calculated Color Zones to the TK7 panel. Much better blending at the edges than Color Range masks, but they are still limited since there are just six Color Zone masks that can be calculated.

Infinity color masks completely eliminate both these shortcomings. They can be built around ANY color and the blending edges are excellent. In fact, you get to choose both the color AND the edge feathering as you create the mask. Infinity color masks add a whole new dimension to the masking experience because they indeed work in a completely different dimension in the 3-D color model compared to luminosity masks.

3-D Color Model

These new masks are dead-on accurate, have perfect blending edges, and are programmed with an amazing level of intuitive control so they are easily customized. They’re also true 16-bit masks (of course). No 8-bit selections are involved anywhere from creation through deployment. Infinity color masks are definitely better than luminosity masks when you need to make a color-based mask.

Once you install the update, to generate an infinity color mask, go to the SOURCE section of the TK7 RapidMask module and click the Color > Choose menu item.

Choose color option

This opens the Color Picker where you select a color from your image to build the mask around. The RapidMask module then calculates a starting mask and displays it on-screen while the new Infinity Color Mask control window opens on the RapidMask module.

Infinity Color Mask window

While infinite control is possible with these new color masks, you’ll likely find the initial mask generated from the Color Picker selection to be quite good. It properly isolates the selected color and provides the correct feathering for most adjustments and selections. Once you’re satisfied with the mask, clicking “OK” outputs it as a Rapid Mask and then all features in the MASK, MODIFY and OUTPUT sections of the RapidMask module can be used to adjust and deploy it. Infinity color masks are amazing and quite possibly the next masking revolution. They will quickly find a place in any workflow.

“My Channels” is another new masking option and it’s found at the bottom of the SOURCE > Channel menu.

My Channels option

This feature was recommended by another user and I’m a little embarrassed I didn’t think of it sooner as it makes perfect sense for a full-featured masking panel like the TK7 RapidMask module. However, the coding for it is somewhat complicated, so waiting this long has likely resulted in a better overall implementation.

Clicking “My Channels” scans the immediate document environment for user-created masks and selections. This includes:

  • User-created alpha channels on the Channels panel
  • The layer mask of the active layer on the Layers panel (if it has a layer mask)
  • An active selection (if one exists)

It then lists all these options as individual buttons in a new window on the RapidMask module.

My Channels list

Clicking one of these buttons turns that “channel” into the new Rapid Mask. From there, all the buttons in the MASK, MODIFY, and OUTPUT sections of the RapidMask module can be used with it. “My Channels” makes it possible to bring any masks you’ve created and/or saved into the Rapid Mask process, and this includes using them with the mask calculator. So the RapidMask module now not only works with the masks it generates, it also works with any of the user’s own personal masks and selections. This greatly expands the possibilities for making highly custom masks that combine pixel-based masks from the module with detailed masks of specific elements the user has already created. The video above explains how “My Channels” masks work.

In addition to the new mask options in this TK7 update, there are also a couple smaller changes. One that improves workflow efficiency is the new “I/M” buttons.

Image/Mask toggle button

These are simply single buttons that toggle between viewing the composite image and viewing the current mask. You don’t have to move your mouse between separate “Image” and “Mask” buttons anymore to do this. You can just keep your mouse in one place and click repeatedly to check your mask against the actual image. The new I/M buttons are available in the main Rapid Mask interface (above), in Layer Mask mode, and in the new infinity color mask control window.

The last update is the addition of a “Feather Selection” step in the Mask-the-Rapid-Mask MODIFY option.

Image/mask-the-rapid-mask

The action now stops with a suggested feather pixel radius for the masking that will be applied with the user’s active selection.

Feather option

This feather selection blurs the edges of the selection mask to help insure smooth blending. In the original version of the TK7 RapidMask module, this automatically occurred using a calculation based on the size of the image. Some users preferred a different amount of feathering or none at all. To accommodate the different possibilities, the action now stops and lists the calculated pixel radius for the feathering. The user can accept this, adjust it if they choose, or, if they want no feathering at all, click “Cancel,” in which case the action completes without adding any additional feathering to the user’s active selection.

I’m pleased that the TK7 panel is able to continue to evolve in a positive fashion. Infinity color masks are a big improvement, and “My Channels” offers a new level of masking control. And I’m happy to be able to provide these new features as a free update to customers who already have the TK7 panel. If you don’t have the TK7 panel yet, you can get a 20% discount on the updated version for the next couple of weeks with the following discount code: Update20

This code takes 20% off anything on the Panels & Videos page, so it’s a good time to shop for both panels and videos.

The TK7 panel for Photoshop CC

I’m happy, excited, (and somewhat relieved) to finally announce the release of the TK7 panel for Photoshop CC. This is a major update to the TKActions V6 panel and there are lots of improvements. New functions, new actions, new buttons, new masks, new workflow possibilities, and new options for creating, modifying and outputting masks. But perhaps the best news is how little the panel has actually changed visually. The V6 architecture is a robust platform, and all the new TK7 features fit on it easily. If you’ve been using the V6 panel (or even the free Basic V6 panel), then it will be easy to adapt to the TK7 panel. Most buttons, menus, and functions are still in the same place. They have just been upgraded and enhanced with the new TK7 functions.

The video at the bottom is a broad overview of the TK7 panel and covers many of the new features. Some of the most important improvements are listed below.

ALL MODULES

  • Automated installation−Manual installation no longer required. There are installers included in the download folder to properly install the different modules on your computer’s hard drive.
  • Easy update−Many of the user-saved values, like language choice and user action names from the V6 panel, transfer automatically to the TK7 panel.
  • Buttons are 20% larger.
  • Rollover help is accessed by holding down the ALT button (Mac: option button).
  • Smart blur−The panel calculates what it thinks is an optimal feather or blur radius for many actions (but users are still given the option to change it if they want).

COMBO/Cx MODULES

  • Several new and/or improved actions−Spotlight, Freehand Vignette, RGB ↔ Lab , Dehaze, and Add Color
  • Multi-dimension web-sharpening. (This has been added to the Batch module also.)
  • New buttons: Content-Aware Fill and disable/enable layer mask.
  • CTRL/command functions have been added for several buttons to provide alternate placement for the new layers the buttons create.
  • The adjustment layers menu is easier to open so that new adjustment layers can now be accessed with one-click.

RAPIDMASK MODULE

  • Rapid Mask engine generates masks approximately 20% faster.
  • New Color Zone masks.
  • New CMYK masks.
  • Single-slider modify option to “infinitize” any mask using an on-module Levels adjustment.
  • New modify functions−Camera Raw filter, black brush, white brush, burn, dodge, Brightness/Contrast, and mask-the-mask.
  • “Keep Channels panel clean” option automatically removes the channels used to create masks.
  • “Quick Paint” buttons make mask painting faster and easier.
  • “Auto-hide selection edges” option so you don’t have to deal with marching ants when preparing to paint through a luminosity selection.
  • CTRL/command options to provide alternatives in layer placement when outputting masks.
  • Filter Mask option for applying masks to smart object layers with smart filters.

Sean Bagshaw has created a new TK7 Video Guide to walk users through all the functions of the TK7 panel, old and new. The video series has new videos, new techniques, new demos, and new sample images for users to practice along. If you’re familiar with Sean’s teaching style, you know how good he is at explaining everything. There’s a lot of functionality packed into the TK7 panel, and Sean’s new videos cover it all. Watch samples.

You can get the TK7 panel and the TK7 Video Guide on the Panels & Video page, and right now there is a 40% discount programmed into both items. Simply add the items to the shopping cart and the discount is automatically applied. The introductory discount makes this a good time to purchase or upgrade to the new panel. I hope you’ll give it a try.

In addition to Sean Bagshaw, I’m also fortunate to be working with Antonio Prado in Spain, André Distel in Germany, Isabella Tabacchi in Italy, Rafael Coutinho in France, Roy Yuan in China, and Luca Libralato in developing the panel and creating educational materials for it. Their photography is inspiring and their expertise at translating the panel into their native language has opened these techniques to a much larger audience. There are links to the versions they helped create on the products page.

TK Actions Quick Tip: Reusing saved luminosity masks

Sean Bagshaw recently posted another Quick Tip video covering how to save and reuse luminosity masks. The TKActions V6 panel has the “Channel” button in the OUTPUT section, which saves the luminosity masks it generates, already programmed in. So the saving part is pretty easy. But the panel doesn’t know when you want to actually recover and use the saved mask, and that’s where Sean’s video comes in handy. He’ll walk you through a couple of different methods to add the saved mask to a layer on the Layers panel. Saving and reusing masks on the Channels panel is somewhat of an advanced technique, but it’s helpful to be aware of it for those situations where you’ve spent a little time creating a particularly useful mask that you might want to use again later on.

Another option for reusing and duplicating a previous luminosity mask is to use one already deployed as a layer mask on the Layers panel. To reuse a layer mask, simply ALT/option+click on the mask and drag it to the layer where you want to use it. Photoshop will duplicate the mask and add it as the layer mask on the second layer. While this is a relatively easy maneuver, layer masks can sometimes get a little messy if you’ve painted on them to conceal or reveal how the mask affects the layer it’s attached to. Channel masks, like Sean demonstrates in the video, can be used to save an original version of a mask that can then be further altered with painting or other adjustments after it’s turned into a layer mask.

Be sure to subscribe to Sean’s YouTube channel for more great tips on photography and post-processing including those listed below.
Quick Tip: Reusing saved luminosity masks
Quick Tip: Developing a quality night sky
Quick Tip: Split toning
Quick Tip: Cloud sculpting
Quick Tip: Exposure blending
Quick Tip: Favorite new V6 features

TK Actions Quick Tip: Split toning

Sean Bagshaw posted another great Quick Tip video on his YouTube channel. Split toning is the topic this time and the new video shows how to customize the technique using luminosity masks. It goes well beyond the split toning capabilities of Light Room and highlights how the TKActions V6 panel and Photoshop provide a more refined approach to this process. Sean covers a lot of territory in this one. Here are some key steps to watch for in the video below:

  1. Separately tone two copies of the same image in Light Room/ACR−one warm, one cool.
  2. Open them as smart objects in Photoshop and stack them as one document.
  3. Use Layer Mask Mode in the V6 panel to make a luminosity layer mask for one of the images that correctly reveals the desired toning in that image.
  4. Modify the layer mask using things like a Curves adjustment and the Paint Brush tool.
  5. Use the smart objects to take the images back to LR/ACR to enhance the effect as needed.
  6. Fine-tune the split toning even more in Photoshop by adding adjustment layers specific to each images’ toning.

There’s an incredible amount of control possible with the steps Sean demonstrates here. I was impressed how the whole mood of the image changed as a result of the split toning process. The sun was above the background mountains in the original image, but not low enough to be casting a lot of warm light into the scene. However, with split toning, Sean essentially took this light and created an image that in the end has a strong golden hour feel to it, even creating some warm backlighting for the trees on the ridge. It’s a very pleasing transformation. I’m sure you’ll enjoy seeing how Sean does this.

Quick Tip: Split toning
Quick Tip: Cloud sculpting
Quick Tip: Exposure blending
Quick Tip: Favorite new V6 features
Be sure to subscribe to Sean’s YouTube channel for more tips on photography and post-processing.

Saturation Masks 2: How to make and use “true” 16-bit saturation masks

The first blog in this saturation masks series reviewed why Photoshop’s HSB/HSL filter is NOT a good way to create saturation masks because it consistently overstates the saturation of dark colors in the image. This post will review the method to make “true” 16-bit saturation masks that accurately map saturation in both light and dark colors. This results in perfectly feathered saturation masks for all colors in the image at all brightness levels. The best methods for using these true saturation masks, and their vibrance mask counterparts, will also be discussed. The video at the bottom of this blog reviews all the information on saturation and vibrance masks in this and the previous blog.

The image below is from the video. To see its true saturation mask, roll the mouse over the image. (The mask may take a couple of seconds to load and the rollover might not be visible in the email feed.) Notice how just the most saturated colors (orange clouds) are light in the mask. Unsaturated and dark colors are dark in the mask. Colors of intermediate saturation (blue in the sky) are shades of gray. This is a very accurate saturation mask, and it’s the starting point for making adjustments to control saturation that are equally precise. NOTE: The Granger Chart image will also be used in this blog. Copies of these images are included in the assets download folder for this blog.

There are good reasons for wanting to make saturation masks better than those created by the HSB/HSL filter. The primary one is accuracy. Creating saturation masks that properly reflect pixel-based saturation makes it very easy to use them to modify saturation in the image. Increasing or decreasing saturation, either globally or locally, can be precisely controlled once an accurate saturation mask is available. Many people have found HSB/HSL saturation masks less than useful because they end up with masks that include too many unsaturated dark colors. Inaccurate masks lead to flawed adjustments. Once a precision saturation mask is available, though, saturation adjustments become a standard part of the workflow since they offer consistent, predictable results. Another reason to make a better saturation masks is to aid in decision making. An HSB/HSL saturation mask is so obviously inaccurate that it’s hard to decide whether or even how to modify it to make it work. Once true saturation masks are available, it’s easy to quickly look at them and decide which one to use or how to make an adjustment to the mask to make it fit the image.

True saturation masks are actually quite easy to make, though the method is not entirely obvious. Start with a Selective Color adjustment layer and set the color change to “Absolute” in order to make sure the necessary adjustments are independent of the amount of color actually present in each pixel. Then for all the colors in the “Colors:” drop-down menu (Reds, Yellows, Greens, Cyans, Blues, Magentas), move the “Blacks” slider all the way left to -100%.

Selective color adjustment

For all the non-colors in the “Colors” drop-down menu (Whites, Neutrals, Blacks), move the “Blacks” slider all the way right to +100%.

Selective color adjustment

This Selective Color adjustment drains all the color from the image. So it’s now essentially a gray-scale image even though it’s still in RGB Color mode. But this gray-scale image is what the true saturation mask looks like. In order to make an actual mask of it, simply duplicate any of the color channels on the Channels panel since they’re all identical at this point. Once the duplicate channel is available, the actual Selective Color adjustment layer used to create it can be deleted. A Photoshop action to complete these steps is included in the assets download for this tutorial.

This duplicate channel is the true 16-bit saturation mask. This is the process carried out in the background when the RapidMask2 module creates a saturation mask. It results in a very accurate saturation mask that can be further modified using the buttons on the panel if adjustments are needed to better target specific colors or parts of the image.

The image below shows the Granger chart with its true saturation mask. Notice the smooth transition from saturated to unsaturated colors in both the light and dark tones in the image.

Granger chart plus saturation mask

Saturation masks, however, are really only half the story. Just like there are two main types of luminosity masks, lights and darks, there are also two types of saturation masks: saturation and vibrance. And, again, just like with luminosity masks, they are the inverse of each. Inverting a saturation mask creates the vibrance masks, and both masks are useful when balancing saturation in an image.

Granger chart plus saturation mask

Armed with these two types of saturation masks that accurately reflect true saturation in the image, it’s quite easy to become a saturation ninja, expertly controlling image saturation to your liking. There are just two main techniques to master:

  • Saturation painting through a saturation mask, and
  • Using vibrance masks as a layer masks on a Hue/Saturation adjustment layer

However, knowing which technique to use is important.

SITUATION #1: OVER-saturation

TECHNIQUE TO USE: Saturation painting through a saturation mask.

RATIONALE: Usually there are just isolated areas of over-saturation in an image, often as a result of aggressive processing. Rather than making a global saturation change to correct this, it’s often easier, and more precise, to simply paint it away with saturation painting. This is the equivalent of dodging using luminosity painting and is described in more detail in this tutorial.

HOW TO DO IT:

  1. Create a blank pixel layer set to Saturation blend mode.
  2. Create a true saturation mask and load it as a selection.
  3. Select the brush tool and set the foreground color to gray and the opacity of 5 to 10%.
  4. Paint through the active selection on the over-saturated parts of the image. The active selection of the true saturation mask will restrict the paint to landing on just the most saturated areas of the image, partially removing saturation in the process.
  5. Add additional brushstrokes until the desired level of saturation is achieved.

WHY IT WORKS: Saturation blend mode combines the saturation of the saturation painting layer with the hue and luminosity of the underlying layers. Gray paint has a saturation of 0%. So if gray paint is painted on the saturation painting layer at 100% opacity, the result would be that the underlying color would now be 0% saturated. In other words, all color would be removed. Painting with a brush opacity of 5 to 10% means that the saturation of the underlying colors will be decreased proportionally. A true saturation selection can be used to expertly confine the paint to just the most saturated colors in the images. Painting through a saturation selection with a low opacity brush and multiple brush strokes then provides a very controlled method for lowering the saturation of just the over-saturated parts of the image, which are defined by the active saturation mask selection.

SITUATION #2: UNDER-saturation

TECHNIQUE TO USE: Use a Hue/Saturation adjustment layer with a vibrance mask as the layer mask.

RATIONALE: Under-saturation in an image is often more global. The image simply looks dull when it doesn’t have enough color. While additional saturation could be painted in with saturation painting (by painting with saturated red instead of gray through a vibrance mask), large parts of most images can usually benefit from a global increase in saturation as long it’s restricted to less saturated colors, which is exactly what a vibrance mask does. So it’s often better to do a global adjustment with an adjustment layer rather than a precision adjustment with a paintbrush.

HOW TO DO IT:

  1. Create a true vibrance mask. The initial vibrance mask will usually be too revealing, so narrow the range. I like using a Zone 8-½ or Zone 9 vibrance mask as my starting point for enhancing under-saturated colors.
  2. Create a Hue/Saturation adjustment layer with the chosen vibrance mask as the layer mask.
  3. Open the Hue/Saturation properties and drag the saturation slider to the right to achieve the desired degree of saturation across the image.

WHY IT WORKS: The vibrance layer mask insures that the adjustment only targets the less saturated tones in the image. More saturated colors will NOT receive the adjustment so they won’t over-saturate with this process. The saturation boost only affects dull colors in the image because the vibrance mask controls which pixels are affected.

SUMMARY: True 16-bit saturation masks are easy to create with a Selective Color adjustment layer. Once the initial saturation mask is created, it can be inverted to create a vibrance mask. With these two masks, there are two main methods for balancing image saturation.

  1. Saturation painting with gray paint through a saturation mask is a precision method for addressing over-saturation of specific colors or elements in an image.
  2. A Hue/Saturation adjustment through a vibrance mask is a great way to bring additional saturation to under-saturated tones while sparing more-saturate colors from the adjustment.

Saturation changes to an image can be subtle, but I usually experiment with both techniques when the image is nearing completion. It’s often surprising how specifically addressing saturation in this manner can improve the image.

It’s worth remembering that saturation and vibrance masks made with the Selective Color adjustment are pixel-based masks, which makes them completely self-feathering. This means that any change you make using these techniques always blends seamlessly into the final image.

The video below reviews and demonstrates all this information about saturation masks. If you would like to practice along, a jpg of the image used in the video is located in the assets download.

Saturation Masks 1: The problem with Photoshop’s HSB/HSL filter

In addition to my work advancing luminosity masks, I’ve also been a big proponent of saturation masks. I’ve used them since 2007 when I first started writing about saturation masks and saturation painting. The way I originally recommended making them was Adobe’s HSB/HSL filter. However, Adobe stopped including the filter in Photoshop for a number of years, so I changed to a different and ultimately better method to make saturation masks. Adobe has again included the HSB/HSL filter in the Filter menu of Photoshop CC. Now that it’s returned, this is probably a good time to review why it should NOT be used to make saturation masks.

TK Basic V6 panel

The way to run the HSB/HSL filter is to create a stamp-visible layer of the image and then convert it to HSL (Hue, Saturation, Lightness) with the filter. Once this is done, the new “Green” channel is used as a saturation mask. Sounds easy, but it’s flawed. A saturation mask created by this process poorly matches the saturation in the image, especially for dark colors.

This first blog covering saturation masks will take a closer look at the HSL/HSB filter and the asymmetry problem associated with it. It’s helpful to understand the problem before moving on to the solution. To do this, I’ll use a Granger Chart, shown below, for illustration since it makes the HSB/HSL problem quite obvious. A copy can be downloaded here. (NOTE: There are some color artifacts in the image on this blog as a result of converting from ProPhoto to sRGB for display on the web.)

TK Basic V6 panel

In the Granger Chart, the most saturated colors zigzag across the vertical center of the image. Saturation will vary somewhat depending on hue, but moving vertically, either up or down away from the center, leads to colors with decreased saturation. The saturated colors in the middle gradually transition to 100% white on the top and 100% black at the very bottom. Black and white have no color at all and so, by definition, are completely unsaturated (saturation = 0%). In other words, pixels close to the center are highly saturated, and saturation decreases in a gradual manner as you move towards the top and bottom edges.

And this is indeed what happens according to Photoshop’s Color Picker when moving vertically from the center to the top edge. The image below shows saturation values from the Color Picker at evenly spaced points along the vertical axis. As you move up from the center (Saturation = 100%), saturation values decrease progressively as distance from the center increases. Exactly as expected.

TK Basic V6 panel

But look what happens as colors get darker. Saturation values, again extracted from the Color Picker, do NOT decrease when moving downward from the center. As colors get more black and contain less color, saturation values don’t change. Saturation remains at 100% even though the amount of color present is gradually decreasing. Even the very bottom pixel of the Granger Chart still has a saturation value of 98% according to the Adobe Color Picker. Strange, huh? Why does saturation remain unchanged as color intensity decreases and black increases? And why are the dark colors different than the light colors?

The actual saturation mask produced using the HSB/HSL filter (the “Green” channel after converting to HSL) matches values from the Color Picker. It is shown below. As a quick review, a saturation mask shows white or light gray in saturated colors and shows black or dark gray in unsaturated colors. For light colors, the HSB/HSL-produced saturation mask shows a smooth decrease in saturation, fading from white to black when moving from the center towards the top edge. This is exactly as expected. The central intensely colored pixels are highly saturated and show as white in the saturation mask. When moving towards the top, saturation decreases, so the mask turns gradually darker gray until it is entirely black at the top border, which is white in the image (and therefore 0% saturated).

TK Basic V6 panel

But look what happens with this HSL mask in the dark colors. The dark colors in the image remain pure white in the mask (indicating very high saturation) even though they contain less and less color when moving from the center towards the bottom. Yes, this matches the saturation values derived from the Color Picker, but it ignores the obvious fact that color saturation actually decreases gradually as you move lower from the center of the Granger Chart. There is no corresponding smooth transition in the saturation mask of the dark colors like in the light colors as would be expected.

This is the asymmetry problem that comes from using the HSB/HSL filter to produce saturation masks. Light colors show appropriate saturation and feathering in the HSB/HSL saturation mask, but dark colors show exaggerated saturation and no feathering at all.

The important thing to take away in all this is that a saturation masks created using the HSB/HSL filter significantly (and sometimes grossly) overstate saturation in dark colors of the image. Dark colors end up being mapped as more saturated than they really are. This is also demonstrated in the image below. Its HSB/HSL saturation mask is shown beside it. Notice how the letters and numbers, even though they are nearly black, are showing as a very light gray in the saturation mask created using the HSB/HSL filter. This indicates they contain highly saturated colors. But this is obviously wrong. No way does a color this dark have the degree of color saturation indicated by the mask. Black is 100% UNsaturated, and any colors approaching black should be very dark in a mask that accurately maps color saturation. But in this mask, the characters in “OPEN” and “7 TO 7” are very light. Based on these tones in the mask, their color saturation in the image should exceed that of the deep blue sky (which is a darker gray) and approach that of the reds and yellows in “GRILL” (which are also very light gray). Even worse, the black word “GEARHART” is mapped in the mask as being more saturated than the magenta background behind the hamburger bun. These characters are clearly less saturated than this. So this isn’t just a theoretical concern that happens in a mathematical image like the Granger Chart. The same problem of the mask showing over-saturation of dark colors is also quite obvious and quite extreme in an actual image.

TK Basic V6 panel

NOTES:

  1. The question can fairly be asked as to why these dark colors aren’t actually pure white in this saturation mask of the image as the dark colors are in the Granger Chart? I’m not entirely sure, but I think this probably relates to the way the Granger Chart is created. It’s made from two gradients: one of completely saturated colors and the other of black-to-white tones. I have a feeling that the colors it produces are only a subset of all colors (even though it creates what appears to be a spectrum of all color) and it’s these specific dark colors that get mapped to 100% saturation by Adobe’s Color Picker. Although, it may also be related to how Photoshop converts from RGB to HSL. Or it could be some other reason entirely. The Granger Chart happened to be what I was using when experimenting with saturation masks, and was what tipped me off to the HSB/HSL problem of dark colors appearing more saturated than they really are. But the over-saturation of dark colors has been apparent in all “real” photos that I’ve made saturation masks for using the HSB/HSL filter. The over-saturation of dark colors is seldom 100%, like with the Granger Chart, but it is always very obvious once you’re aware of it and start comparing the saturation of dark colors with other, truly more saturated colors in the image.
  2. It is also worth noting that there is still some self-feathering of the of the over-saturation in HSB/HSL-produced saturation masks in “real” images. There is no abrupt cutoff like with the Granger Chart HSB/HSL saturation mask. So using these HSB/HSL masks would still lead to a smooth blending of whatever is adjusted through such a mask. However, visually evaluating these HSB/HSL-created masks to decide where saturation is truly present in the image is nearly impossible since the dark colors end up being so light in the mask that they frequently outshine actual saturated colors. The bottom line is that any adjustment through such a mask intended to affect actual saturated colors in the image disproportionately affect darker colors in the image instead.

SAT mask menuWith the problem described, the question becomes how to make a more accurate saturation mask, one that treats light and dark colors equally so that the saturation in darker colors gradually tapers off as saturated colors are replaced with unsaturated black. What that mask looks like for the Granger Chart is shown below and was generated using the “SAT” mask option in the TK RapidMask2 panel. It shows perfect saturation feathering in both light and dark tones. This is easily achieved when using a better method than HSB/HSL to generate TRUE saturation masks.

TK Basic V6 panel

Below is the test image along with the more accurate saturation mask generated from the RapidMask2 panel. The most colorful areas are now the brightest shades of gray in the mask and elements with little or no color (the words “OPEN”, “7 to 7”, and “GEAHART”) are very dark gray. This is exactly the way it should be in a pixel-based mask that accurately maps color saturation.

TK Basic V6 panel

I’ve been using this more advanced method for making saturation (and vibrance) masks in my panels and developing workflow for close to a decade and wouldn’t return to using the old HSB/HSL filter at this point even though Adobe once again makes it available. I’ll explain how to create these TRUE saturation masks in an upcoming blog.

SUMMARY: Saturation masks produced using Photoshop’s HSB/HSL filter display asymmetrical saturation when comparing light and dark colors. Light colors show a perfectly feathered saturation transition as colors get lighter and less saturated while dark colors get mapped as being more saturated than their color would suggest. A better method for making saturation masks would take into account pixel brightness as well as saturation.

FINAL NOTE: I’m not an expert in color models and do not know why the HSL/HSB filter maps saturation the way it does or why the Saturation values in the Color Picker remain at 100% for dark colors. I just know that pixel-based masks need to accurately display the pixel-based values I’m looking to adjust if they are to be useful. That way I can properly evaluate the mask and modify it, if need be, to match my image. In the case of saturation masks, the HSB/HSL filter is definitely substandard for creating the type of masks I want to use.