Learn how the relationships between these three important adjustment tools can enhance your photos…
The Clarity, Vibrance and Saturation tools are some of the most useful adjustments for enhancing digital images.
While most people understand what is meant by ‘clarity’ and many can comprehend ‘saturation’, the concept of ‘vibrance’ is relatively new and often poorly understood. So even though most image editors provide adjustments for clarity, vibrance and saturation, many photographers are unsure about what each tool does and how best to use it.
The Clarity, Vibrance and Saturation sliders (circled in red) are grouped together in the Basic panel in Adobe’s Camera Raw and Lightroom applications.
Locating the Vibrance and Saturation controls in Photoshop.
The Clarity slider is a fairly new tool that has only been available in a few raw file converters. It’s provided in Phase One’s Capture One 7, and Adobe’s Camera raw and Lightroom applications. It’s available as a plug-in for Photoshop, Photoshop Elements, Aperture and iPhoto from Topaz Labs. Unlike the Vibrance slider, it hasn’t yet been added as an adjustment layer in Photoshop.
Clarity adjustments perform a similar function to contrast adjustments. However, while the Contrast slider applies an even level of adjustment across all tones in the image, the Clarity slider works almost entirely on the midtones of the image, as shown in the examples below. In Photoshop and other Adobe applications it also applies a low level of unsharp masking with a high radius setting.
The effects of moving the Clarity and Contrast sliders to the 100% positions, compared with an unedited image. Note the differences produced by these tools on the amount of detail you can see in the adjusted images.
The saturation tool is the most commonly-used (and over-used) adjustment of colour intensity in digital imaging. As is the case in all image editors, you’ll find saturation is boosted by default in JPEG images recorded by almost all consumer cameras, as well as camcorders and smart-phones, because brightly-coloured pictures with strong colours are more engaging than pictures with subdued hues.
Regardless of which editor you’re using, when you move the saturation slider to the right you intensify the colours in the image. Move it all the way to the left and the colour intensity is reduced until the image changes from colour to black and white.
The main problem with adjusting saturation is that the tool acts linearly, applying the same boost to colour intensity across the spectrum. Increasing saturation can affect different colours differently because areas with different colours usually have different base levels of saturation at the point of capture, reflecting the natural intensities of hues in the subject.
This means one colour can become over-saturated before another reaches its full potential.
The results begin to look artificial because areas that are over-saturated lose detail due to saturation clipping.
Over-saturation can push the brightest and/ or darkest areas in one or more of the three colour channels (red, green and blue) beyond their linear range, causing them to become ‘clipped’ to solid black or white. Clipped channels can’t reproduce the full potential tonal range in an image.
We first encountered the Vibrance tool in Pixmantec’s RawShooter Essentials, an excellent raw file converter that was originally offered as freeware in 2005. When the Vibrance tool was first introduced in 2006, it was little more than a novelty, although it was so clever (and popular) it has now been adopted by most serious image editors and raw converters, albeit in slightly modified versions.
The Vibrance tool was developed to prevent saturation clipping by boosting colour intensity selectively. Areas that are already colourful receive less adjustment than those with lower colour intensity.
The effects of moving the Vibrance and Saturation sliders to the 100% positions, compared with an unedited image. Note the differences produced by these tools on hues that are already quite vivid and how over-saturation can clip details.
Using the Tools
Essentially, the Contrast and Saturation sliders are relatively blunt tools, whereas the Clarity and Vibrance sliders provide a considerable degree of fine control.
Contrast and Clarity: The Contrast slider expands or shrinks the overall range of tonal values in the image. When it is moved to the left, the contrast is reduced and the range of tones expands; when moved to the right, the range of tones contracts.
Clarity works in a similar way to contrast but only affects the mid-tones in the image, rather than operating globally on the entire image like contrast. Most photographers use the Clarity tool for applying just enough edge contrast to bring out crisper detail, without producing the halo artefacts associated with over-sharpening.
Success with this tool is very image-dependent ““ and it may not be advantageous with some shots. You must simply try it out to see what changes, being careful not to overdo the adjustments. Always zoom in on processed images to check for processing artefacts and don’t be afraid to tweak other sliders, particularly the exposure, shadow brightness and contrast, to compensate for artefacts that are just visible.
An example of an image that was improved quite dramatically by a simple increase in contrast.
Saturation and Vibrance
The Saturation slider applies a linear colour boost to all colours. If it’s applied to colours that are already intense it can push them past the maximum points for one or more channels.
The Vibrance slider applies a non-linear colour boost, increasing saturation in more muted hues while moderating the boost given to already-saturated hues.
Moving the Saturation slider to the right will emphasise colours that are already relatively bright. You can then bring up colours with less impact with the Vibrance slider.
If you want less colourful areas in your image to stand out, consider lowering the saturation before increasing the vibrance. But if you want the most colourful areas to dominate, reduce the vibrance and then increase the saturation.
Be clear about which colours you want to boost. Aim to achieve the best-looking balance between saturation and vibrance, without over-saturating any colour.
The Vibrance tool is often used for boosting the strength of brighter colours without pushing skin tones to the point where they begin to look artificial. It’s particularly effective when subjects are wearing bright, primary colours.
For all of these adjustments, your eyes will be the best judge of how far to push each slider in either direction. Unfortunately, most of us prefer highly-saturated colours. We’ve come to expect high saturation (particularly in warm hues) as a result of watching years of over-intense colours in movies, TV programs and printed photos.
A small boost to saturation can be attractive. But this control should be used with a light touch if you want to retain a natural-looking appearance.
The saturation slider can also be used to subdue colours and impart a muted tone to images. Moving the slider all the way to the left will subdue all hues and leave you with a black and white image.
An example of an image that was improved quite dramatically by a simple increase in saturation, which brought out the ‘warmth’ in the colours of the rocks.
Most cameras provide in-camera adjustments for saturation and contrast, although they don’t include clarity and vibrance controls. In some cases the saturation and contrast adjustments are discrete controls; in others they are combined in ‘picture style’ settings such as Vivid and Landscape. Users can seldom tweak these in-camera pre-sets to anything like the same degree as they can with editing software.
Our general advice to photographers is to capture images as raw files and then tweak parameters like contrast, clarity, saturation and vibrance when converting the files into editable formats (JPEG or TIFF). This provides a much greater degree of control than you can obtain with in-camera adjustments.
Besides, in-camera adjustments are only applied to JPEGs and when they are applied they are locked into the file. If you don’t like them, you’re stuck with them ““ unless you’ve also captured an unprocessed raw file as a back-up.
Article by Margaret Brown
Excerpt from Photo Review Issue 62