Balancing Skin Tone and Creating Skin Tone References

Apples are red, grass is green, and the sky is blue. But what colour is skin?
Skin gives us probably the most complex range of colours in photography, ranging from the lightest to the darkest of a varying combination of colours we might identify as red, yellow, orange, pink, brown, and black. All but the very fairest skin even contains a bit of cyan.

Reproducing skin tones in your final photographs and prints can be done by eye, but you will be leaving a great deal to chance. Even when working with a carefully colour managed workflow, our eyes are easily deceived. We see skin in the midst of the colours in the background of the image, the temperature of the lighting used to take the photograph, and the clothes the subject is wearing. To reproduce beautiful, accurate skin tones, we need to learn and use a more precise method of colour management.

Moreover, skin colour varies between people, and not just by ethnic origin but also by individual. To get a grasp of just how much skin colour varies from one person to another, have a look at Angélica Dass’s project, Humanæ. Dass is not creating a technical reference, but her project highlights the technical challenge of photographing and reproducing the staggeringly various colours and shades of human skin.

This tutorial will take you through a two-step process in Adobe Photoshop that will help. First we'll explore how to balance skin colour in photographs consistently and precisely. Second, you'll learn how to make and use references from colour-balanced skin.

Colour Theory and Skin Tones

A review of some basic colour theory will help with the technical process of balancing skin tones:

A Tale of Two Colour Systems

You may recall that there are two colour systems we use in photography. The first, RGB, is the colour system we use with our cameras and computers. Colours in this system are made by combining varying amounts of red, green, and blue. The second colour system, CMYK, is used in printing. Colours in this system are made by combining varying amounts of cyan, magenta, and yellow. Because cyan, magenta, and yellow when combined produce a dark brown and not black, the CMYK system adds a pure black (the “K” in CMYK) as a fourth colour.
Skin tones are usually evaluated using the CMYK system, even when we are working on digital images on our computers. Some people suggest that it’s easier to adjust skin tones using CMYK instead of RGB, but the reason for using CMYK is likely historical. The colour references we use for skin tones were initially developed by printing press operators who work in CMYK. The references have been refined over the years, but still within the CMYK system. There is so much information about skin tones established in that colour system now that it’s easier to use it instead of trying to convert the information to RGB.
But here is something important to know: the two colour systems are not completely different or independent. Rather, they are complements to one another. In fact, understanding how the colour systems complement each other will become important as we begin to adjust skin tone.
To see how the two colour systems work together, open the Colour Balance dialogue in Photoshop (Image > Adjustments > Colour Balance) or look at the Properties in a Colour Balance adjustment layer (Layer > New Adjustment Layer > Colour Balance). Play with the colour adjustment sliders to see how the colour systems work together.

• The opposite of cyan is red. To get more cyan, you take away red, and to get more red, you take away cyan.
• The opposite of magenta is green. To get more magenta, you take away green, and to get more green, you take away magenta.
• And the opposite of yellow is blue. To get more yellow, you take away blue, and to get more blue, you take away yellow.

Colour Systems in Photoshop

It’s also important to know that Photoshop allows us to have information from both colour systems without switching between them. Even though we will be using the CMYK system to evaluate and balance skin tones, we will be working with our image in the usual RGB colour space. We will not be converting our digital files to CMYK.

Skin Tones in CMYK Values

You can find any number of suggested formulas for reproducing skin tones accurately. Image editors each have their favourites. The formulas are usually expressed as relative proportions of cyan, magenta, yellow, and black; for example:

• Find the cyan value; magenta should be double that of cyan, and yellow should be around one-fifth to one-third higher than magenta (20c 40m 50y). 

But as we’ve already established, skin tones vary widely between ethnicities and among individuals. Therefore, the best any formula can give you is a starting place. The following chart is my rough guide of CMYK values for different skin types.

Balancing Skin Tone

We are going to deal with skin tone in two parts. In this first part, we are going to balance skin tone in an image using Photoshop’s Info palette and a Curves adjustment layer. In the second part, we’ll make a skin tone reference from our image.

1. Prepare Your Image

Choose a properly exposed headshot of a person, ideally without a lot of background in the image. If possible, do a basic white-balance on your image before balancing skin tone. The technique we will be using to balance skin tone will correct overall colour balance in your image, but your work on skin tone will be easier if you are not also adjusting for a white balance skewed by basic lighting. If you are uncertain how to colour-balance your image or what it means, one of these Tuts+ tutorials will guide you: Quick Tips for a Perfect White Balance or Better White Balance with the Kelvin System.
You can do other portrait retouching before or after balancing skin tone. Sometimes, it’s easier to do retouching after skin tone has been balanced. In fact, sometimes balancing skin tone removes the need for some retouching. Other times, balancing skin tone helps to smooth out retouching that has already been done. Experiment to get a feel for what works best for you in different situations.

2. Select Your Sample

To begin balancing the skin tone, open the Info palette (Window > Info or F8) and select the Eyedropper tool (I). In the tools options bar, set the Sample Size to sample an area of 11 by 11 pixels (“11 by 11 Average”). If your image is low-resolution, you may want to lower your Sample Size to 5 by 5 pixels.

Select a medium-light area on the skin to sample. Avoid bright highlights; the colour saturation will be too low to provide a good sample. Also avoid the cheeks; women typically have makeup there and men often have ruddy cheeks. The chin, forehead or neck are often good points to sample on a woman’s face. For men, try sampling on the forehead or below the pupils at the very top of the cheekbones. Once you’ve chosen your sample area, Shift + Click on the spot with the Eyedropper tool to set your sample point.
In the Info palette, click on the eyedropper symbol next to the information for your sample point and from the drop-down menu, select CMYK. This will provide you with colour values in CMYK while leaving your image in the usual RGB mode.

3. Evaluate the Colour Information

Evaluate the CMYK numbers for your sample point. For example, in my photograph, the values at my sample point are:

• C - 18 
• M - 48 
• Y - 48 
• K - 1

My CMYK chart for skin tones suggests that for average Caucasian skin, I want about 25% more yellow than magenta. In my photograph, the yellow and magenta values are the same, so I will need to add a bit of yellow.
I also want less cyan than magenta. My chart suggests starting with cyan at about 25% of the magenta. In my photograph, the cyan is about one-third of the magenta, so the cyan may need to be adjusted down.
Caucasian skin typically does not have any black, so I will want to be sure that disappears as I adjust my image. Black (as it’s read in the Info palette) is the result of cyan, magenta, and yellow combined so making adjustments to those colours will change the level of black.

4. Use Curves to Make Adjustments

To make the colour adjustments, add a Curves adjustment layer (Layer > New Adjustment Layer > Curves or select Curves from the Adjustments palette). Select the On-Image Adjustment Tool (the pointing finger) in the Curves property box.
You will be working in the individual Red, Green, and Blue channels of the Curves adjustment, so remember:

• To add yellow, take away blue; or to reduce yellow, add blue.
• To add magenta, take away green; or to reduce magenta, add green.
• To add cyan, take away red; or to reduce cyan, add red.

Working one channel at a time, click and hold on the sample point you set on the skin and move the cursor up or down to adjust the curve, adding or reducing colour as you need. The numbers in the left column in the Info panel will be your starting point. The numbers on the right are your adjusted numbers.
In my photograph, I began by working in the Blue channel to add yellow, then switched to the Red channel to remove cyan. Adjusting one channel will affect another, so you may have to make small adjustments, switching back and forth between channels until you have the colours where you want them.

5. Adjust Saturation and Tweak

Adjusting colours will affect the colour saturation of your image. So, after you’ve made your colour adjustments with Curves, adjust the saturation by adding a Hue/Saturation adjustment layer (Layer > New Adjustment Layer > Hue/Saturation or select Hue/Saturation from the Adjustments palette). Decrease the Saturation as needed.
Don’t be surprised if you find yourself going back and tweaking your Curves adjustment layer after you’ve reduced the saturation. You may also want to adjust the overall density of your image (how dark or light it is) by selecting the RGB channel in the Curves adjustment layer and nudging the overall curve (the white line in the graph) up or down.

Once you are satisfied with the skin tone in your image, save a copy before moving on to the next step.

Before

After

The Reference Index: Quantifying Skin Tone

Now that you have a skin tone you’re happy with, collect a patch of skin to create a skin tone reference index.
Remove any sample points you set in the first stage by clicking on the drop down menu at the top right of the Info palette. De-select “Colour Samplers.” Flatten the image you’ve been working on (Layer > Flatten Image or select Flatten Image from the Layers panel option menu).

1. Prepare Your Samples

Choose the round Elliptical Marquee tool (M) and select a small area of light skin (about 250 to 400 pixels in diameter). Copy the selection onto a new layer (CMD/CTRL + J). Select a similar sized area of mid- to dark skin and copy that selection onto a new layer.
Deselect (turn off) the Background layer. You will now have two new layers, each with one patch of skin. Select the two new layers and merge them together (CMD/CTRL + E or Merge Layers from the Layers panel option menu).
Next run a Gaussian Blur filter on the merged layer (Filter > Blur > Gaussian Blur). Choose a setting that removes any sign of grain or skin texture.

2. Create a Gradient

Select the Gradient tool (G) and in the tools option bar, choose a Foreground to Background gradient, select Dither, and deselect Transparency.
Click on the Gradient picker in the tools option bar to bring up the custom options dialogue box. Click on the colour tag for one end of the gradient and below the tag, in the dropdown options for Colour, select User Colour. Your cursor will change to a pointer. Select one of the two skin tone samples on your layer. At the other end of the gradient, repeat the steps, choosing the other skin tone sample. Name your gradient and save it. Click OK.

Once you have your gradient options set, use the Gradient tool to draw your gradient from left to right, completely across the layer. You will now have a layer filled with a gradient of the skin tones from your image.

3. Save your Reference File

Delete the Background layer. (Double click the layer to unlock it, then delete it.) Resize your image to something manageable (Image > Image Size). An image 1000 to 1500 pixels wide will be lots. For the Resample option in the Image Size dialogue box, choose Bicubic (smooth gradients) from the dropdown menu.

You may wish to use the Text tool (T) and include information about the index directly in the file. For example, I added information about the skin tone and its CMYK values to my index.
Save the file as a Photoshop file (.psd) in a folder you’ve created for Skin Tone References. Name the file clearly for its reference. For example, I named my file “Male-Caucasian-Medium.”

Using Skin Tone References

Now you can refer to your skin tone reference files when colour correcting and doing advanced portrait retouching.

Open the reference file for the skin tone closest to the skin in the image you’re retouching. Use the Info palette and Eyedropper tool as you did in the first part of this exercise to select a sample point in your skin reference file. Make note of the CMYK colour values.
Use the CMYK colour values from your reference file as a starting place to balance the skin tone as we did in stage one of this tutorial.

There are also companies and artists who make their skin tone reference files available on the Internet. Those files that include and are marked with the CMYK values may be helpful, but avoid using .jpg files that come as colour swatches only. Image files saved to the web have been separated from their source colour profile, then compressed and transformed. The CMYK values that you would read off of those colour samples are likely to be considerably off-target.

Conclusion

Balancing skin tone in a photograph is a challenging task but essential for producing a quality portrait. You can balance skin tone by doing a basic white-balance and fine-tuning the colours by eye, but the outcome will be easier and finer if you take the time to assess the colour values in the skin and balance them with Curves. Saving colour samples from photographs with well-balanced skin will give you a reference when colour-balancing other portraits.

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Most tutorials about digital noise are about how to remove it, but I'll show you why we can all show noise a little more love.
Noise has a bad reputation. Most tips treat it as an unsightly blemish, as if it’s some awful abnormality that needs correcting. Handled properly, though, the right kind of noise can add a lot of mood to an image. In this video we are going to look at how to add grain - organic-looking noise - to certain images can create atmosphere and depth.
While grain can separate your pictures from a sea of clinical-looking digital captures, not all images are ideal candidates for such treatment. We discuss the types of compositions and lens choices that will help with this look.

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Meet Lightroom Mobile

by Andrew Childress

I spend a lot of time in Adobe Lightroom. This also means that I spend a lot of time at my desk, working in a Lightroom catalog. Luckily, that's about to change. With the launch of Adobe Lightroom mobile, it's time to take our editing work on the road. I've spent the week trying out this app on my iPad, and today I'm sharing my experience.
When Lightroom 5 launched, there was a sneaky feature included in the release notes: Smart Previews. This feature is what Adobe called "representative RAW files" that are small file size duplicates of your RAW images. Even when you're not on the same drive as your RAW images, you can maintain your previews and edits with Smart Previews. Lightroom mobile uses the cloud-based Smart Previews to reduce the file storage needs.
To get started with Lightroom mobile, you'll need an iPad running iOS 7 or newer (Adobe says that an iPhone app is coming soon). From the app's info, it appears that all iPad iterations except the very first one are supported by the app. Props to Adobe for supporting my aging iPad 2, by the way.
Launching alongside Lightroom mobile is the brand new Lightroom 5.4, which is required for use with the app. To get started with Lightroom Mobile, make sure you update your installation of Lightroom to the latest version.
You'll also need an Adobe Creative Cloud subscription to use the app. If you don't already have one, Adobe will provide a 30-day free trial of Lightroom mobile when you sign in with your Adobe ID.

Getting Started

When you setup Lightroom mobile, your entire catalog won't sync to the cloud. Instead, Lightroom will send selected collections to the cloud. Make sure you are using Lightroom 5.4 and sign in with your Adobe ID before attempting to start syncing.
To get started with a synced collection, start by making sure you have a collection of images built. Then, right-click a collection name in the Collections panel and choose Sync with Lightroom mobile.

Make sure to choose "sync with Lightroom mobile" when creating a new collection. If you forget, you can always right-click an existing collection in the Collections panel to turn it on.

One quirk that I noticed right away is that only one catalog can be synced with Lightroom mobile at a time. Switching catalogs will cause you to lose the synced collections.

Once you've added images to a synced collection, give Lightroom some time to complete the sync. The progress of the sync is shown in the upper left corner.

The iPad App

Let's get this out of the way: the interface is incredible. Although it's different than the desktop version, the tiled layout is stunning. This app could definitely be used to show image collections to clients.

The tiled view of the iPad app is absolutely good enough to bring to meetings with your clients.

After entering a synced collection on the iPad, you're presented with this masonry style layout of your images. Tapping an image brings it into full view, and after a few seconds, it it sharpened and displayed a histogram alongside the image.

For Culling

One of the key parts of a workflow is the culling stage, and I'm finding Lightroom mobile to be fantastic for cutting my image collection down to the keepers. In the lower left corner of the image is a flag icon that can be tapped to toggle an image as a pick.
Even more intuitive is the ability to swipe up or down on the image to flag it or unflag it. Immediately, this app is going to find its way into my workflow to cull image collections down away from the computer.

One of my primary uses for the app will be to cull image sets to the keeper images. I do this using the flagging system, which I can apply by swiping up and down on the iPad.

Of course, the value of Lightroom mobile is that once changes are made on the iPad, they get pushed back to the same images on your computer's catalog. With no more than a minute's lag from my testing, I'm confident that my collections will stay usably synchronized.

For Editing

Much of the editing power of the desktop version of Lightroom is present on the iPad. Adobe should be applauded for not copying and pasting the interface of Lightroom onto the mobile app. Instead, they designed an interface that fits a touch screen device perfectly.
When you tap to open a single image, there are four icons at the bottom of the screen that access the editing power of Lightroom mobile. The far left icon toggles the traditional Lightroom filmstrip of image thumbnails. The second icon opens the full editing options that you're accustomed to.

Tapping the first icon on the far left of what I call the "tools panel" will toggle the filmstrip off and on.

Tapping this icon opens the "editing attributes," like exposure and contrast. Tapping any of those icons opens new set of tick marks that appear over the image. Dragging that slider from left to right works the same as the desktop version of Lightroom. As always, the back and forward arrows are in the lower right hand corner to undo and redo your changes.

Adobe should be applauded for not copying and pasting the interface of Lightroom onto the mobile app. Instead, they designed an interface that fits a touch screen device perfectly.

Tapping the second icon on that tools panel opens the image editing options that we're accustomed to with the full edition of Lightroom.

Once you've picked an attribute to modify like the "whites" level, a new set of tick marks appears over the image. Grabbing the circle and moving it left to right is similar to the sliders of the desktop version of Lightroom.

Editing on Lightroom mobile is that simple. Pick an attribute, slide the point, and your editing changes will take effect. The mobile app temporarily pauses syncing to keep your iPad working quickly, but you can always tap the cloud icon and choose "Sync Now" to accelerate the process.

You can force a faster sync by pressing the cloud icon and choosing "Sync Now."

Once a sync completes, the changes you made on your iPad will be visible in your catalog on your Mac or PC.
Presets
Finally, you can also add presets to your images by tapping the third icon on the bottom of the app. The presets are categorized and you can tap any preset to apply it. From my testing, I did not find a way to add or use "user presets", but let's hope that it makes its way into a future edition of the app.

Presets are available for one click edits in Lightroom mobile. Choosing the third icon on the tools panel will open the option.

Cropping

Beyond the standard editing features, cropping is also available in the mobile app. You can click the fourth icon from that same "tools" panel at the bottom of the app to choose cropping options. Choose an aspect ratio (like square or 4x3) to crop the images to, then tap and drag over the image to change your crop. You can even twist your fingers to correct tilt.

Cropping is another essential feature that is in the iPad app! Complete with aspect ratio selections, custom cropping and tilt correction, this is a full featured tool.

Edit Photos Taken With Your iPad

In addition to syncing via the cloud, you can also import images from the iPad's camera roll. Go out of a collection by pressing the back arrow several times and you'll be at the home screen of the app. Press the arrow in the upper right hand corner to create a new collection. When it's created, you can tap the newly created collection to add images from the iPad's camera roll.
The best part is that these images are reverse synced to your cloud collection, and I transferred the screenshots you see in this tutorial using this option. You can add iPad images to any collection by pressing the "+" button present in the corner.

Sharing

Adobe built in a sharing option to make Lightroom mobile a true portable solution. When viewing an image, choose the icon in the upper right hand corner to choose the iPad's typical sharing pane.

Social share options are available by pressing the icon in the upper right hand corner when viewing a single image.

The normal iOS sharing options will appear allowing you email or message your images. You can also configure the app with your Facebook, Flickr or other social media accounts. Once you've done that, those icons will appear as well.

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My Thoughts

It's no secret that I'm a Lightroom fanatic. I've tried creating my own patchwork mobile solutions, but none were good enough to use. I was bound to like any version of an official app, but I have to be honest, this app impressed me.
This is going to change the way that I work, and untether me from the desk more often. I can definitely see myself spending long car rides culling large collections. The editing functionality is good enough to use and is more than a gimmick. When I get back to my desk, I can pick up on my edits without missing a beat.
One thing that Adobe hasn't made clear is the amount of storage space that will be avilable to your Lightroom smart previews. The typical Creative Cloud account includes 20 gigabytes of storage, but it's not clear if the images go in this same bucket of storage or not. Keep in mind that because they are using Smart Preview technology, the images take far less storage space than the RAW files.
The only thing that might turn some users away is the required tie to Creative Cloud. Personally, I have preferred buying the boxed version of Lightroom and skipping Creative Cloud, but this may change my plans.
I think that this may be a tipping point for many other photographers as well, and the cloud seems to be the way that Adobe is headed. The fact that this has essentially been added for free to the collection enhances the value of Creative Cloud as well.

Wrapping Up

Adobe hit a home run with the release of Lightroom mobile. It's going to find its way into a lot of photographers workflow, mine included. I came in with high expectations and this app met them. I think the power of the app will only grow with future updates.
Have you tried Lightroom mobile yet? How does it fit in your workflow? Let us know what you think about this new app.

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