Editing for Impact – Tonal Adjustments

Editing with impact – Tonal Adjustments

By Dan Segouin

 

Modern cameras have multiple tools and features to manage the tonal ranges of scenes. These tools include built in light meters and scene modes that will analyze the framed scene and produce a recommended exposure to create a recommended image. There are instances, however, especially at sunrise or sunset, where the dynamic range of a scene exceeds the capacity of the camera’s light meter. When this happens, areas of the scene will either be too dark or too bright and will likely also contain unwanted colour casts. As photographers, we can use tools and convenient software sliders to adjust our images to better suit our creative tastes and to render images that have greater impact.

The purpose of this article is to provide guidance and suggestions to create greater impact and improve the readability of an image. These factors do not need to be followed in any order. All basic photo editing software packages that allow for global adjustments to be made to an image use simple sliders that are straightforward and produce nondestructive edits to the source file. These sliders differ from applications that allow for pixel adjustments such as those found in Photoshop, which can be destructive.

As the adjustments are applied to an image, the modifications are shown graphically in the histogram, which is usually located in the top right corner of the software. Using the histogram as the guide, photographers can see the results of their editing decisions and the impacts to the tonal ranges of the image in real time. It is important to remember that these edits are global adjustments and affect the entire image. The adjustment tools discussed will work for colour and monochrome images.

 

White Balance

Cameras have numerous presets for controlling the white balance or colour temperature of an image, all of which can depend on the lighting conditions of the scene. There are specific colour temperatures that are commonly used to warm up colours and tones in an image such as daylight, shade and flash seen during the summer. Temperature presets such as tungsten and fluorescent can create cooler winter effects emulating winter scenes. When choosing an overall white balance for the scene, it is best to alter any existing colour casts within the image to neutral colours to make the scene appear more natural. This adjustment can be made by either applying the presets that most editing software contain, or with a picker tool that can be used to identify a specific part of the image as a neutral colour.

The image below shows a comparison of the adjustments made to an image when using the auto white balance setting versus the adjustment to the daylight setting. The daylight setting increases the warmer tones in the image and creates a very warm glow throughout.

 

Exposure

The exposure triangle of aperture, shutter speed and ISO should be common terms for all photographers. The camera settings coupled with field decisions such as exposure compensation and metering may need adjustments in editing software to create the desired image exposure. Exposure adjustments can result in significant changes as they affect the entire image. By decreasing exposure, images become moody, darker, and potentially more dramatic. By increasing exposure and adding brightness, images can become energetic and lively.

 

Contrast

As exposure can alter the entire image, contrast is an adjustment that is more isolated to the midtones of an image. The contrast adjustment works well to separate objects in an image and accentuate the differences between them, such as surface texture and object detail. This effect takes place in the image as dark areas become darker and brighter areas become brighter, as more contrast is applied to the image. Contrast adjustments are an easy way to apply punch and drama to textures and colours in an image, especially if the lighting is overcast and grey. The midtone range adjustments are often overlooked by photographers and can make subtle changes that make pleasing improvements.

In the following image of a slot canyon waterfall, the lighting was overcast and flat across the surface of the walls of the canyon. The flat lighting reduced the appearance of detail and texture in the scene. With global contrast adjustments, the lighting improved, the colours became deeper and richer, and the texture was enhanced.

 

Tonal Range

Managing the tonal ranges within an image is very important. These ranges will contain detail that can be emphasized or minimized, depending on the artistic taste and intention of the photographer. To target the lighter tones in the image, one would adjust the highlights slider. To adjust the brightest tones, one would adjust the white sliders. These tonal ranges appear on the right side of the Lightroom histogram shown in the image. Editing software will often provide warning indications when the adjustment is too strong, and detail is lost. Using these sliders, one can manipulate the lighter tones, which can add impact and mood to the scene. When images are over brightened, the colour and detail can be lost in specific areas as the contrast is reduced. If lighter areas are darkened, the brighter areas can become unnaturally dark and appear muddy with unwanted pixelation. This result is frequently seen with images that contain overexposed skies. Reducing the brightness damages the pixels and creates an overedited result.

To focus on darker tones in an image, photographers could use the shadows and black sliders, paying attention to the left-hand side of the histogram. With image darkening, it is possible that detail in the shadows will not be visible, which could be a detriment to the image. For the best results it is important to review the histogram as you apply small incremental adjustments.

 

Fine Detail

The next section will focus on the fine detail of an image. The adjustment tools that work with image detail are the texture, clarity and dehaze sliders. These slider tools use specific zones in the tonal range and are very useful for highlighting detail.

For photographers that edit portraits, the texture slider is very useful to help make skin smoother and softer looking by removing texture. By adding texture, landscape photographers can enhance the detail in vegetation such as branches and leaves that may appear within images. This slider works by targeting zones that have sharp edges or drastic colour changes, like the stripes on a zebra. Adding texture will tighten the appearance of the stripes and clean up the transition between the whites and blacks in a zebra coat. When overused, textures become unnatural and distracting.

The clarity slider targets the midtone range of the image so as to add contrast without affecting the highlights and shadows. When clarity is removed from an image, a slight glow will be created. When clarity is added, the image textures will improve, but digital noise may be introduced.

The final contrast adjustment tool is the dehaze slider. This tool mainly affects the midtone range and has many uses. The primary use is to add or remove atmospheric haze within landscapes, and glare from sunlight and reflected windows. The dehaze slider works well to saturate colours in low contrast areas that are in overcast lighting conditions. By removing dehaze, photographers can add atmospheric haze to the image.

 

Vibrance and Saturation

The last section will discuss altering the vibrance and saturation sliders. These sliders affect the entire image and work with colour. Manipulating the colours of an image can help reduce the intensity or dominance of a specific area that may be distracting. Making these changes can also add pop and dynamism to an image that needs a colourful boost.

When the saturation slider is overused, colours will appear unnatural, detail will be lost and very distracting colour banding may be introduced. When saturation is removed from an image, the overall mood can become cool and dreary.

The vibrance slider helps add colour to the image by working with zones in the image that are low in colour and have less saturation. By adding vibrance, colour can be added naturally, which will not create banding or impact detail. This is a useful adjustment for portrait photography as the adjustment will not create unflattering colours in skin.

The following is an example of a mountain scene, captured at the picturesque lookout at Peyto Lake in Alberta. The exposure of the scene was set based on the lightness values of the central peaks. In the first image, the balance of the histogram is weighted on the left-hand side and is too dark. With tonal adjustments, there is an opportunity to bring detail forward and improve the colour in the first image.

 

In the final image, the field of view was reviewed, and the final crop was established to remove tree branches on the left and right sides of the foreground trees. As well, the overall warmth of the image was increased to accent the sunrise colours. The exposure of this image was based on the sunlight on the peaks. The slight adjustment of the exposure helped recover data in the dark areas of the foreground and middle ground. By making further contrast adjustments to the midtones with shadows and highlights, more data was recovered. In addition, the lighter colour tones of the image were increased with the use of the vibrance slider. The dehaze slider helped add more saturation to the colours and added another level of contrast to the midtones. As a final check, the histogram was balanced and stretched across the entire tonal range in the final edit. The histogram for the original image indicated a very high level of darkness, as indicated by the shift to the left side. By using the adjustment sliders incrementally, the resulting histogram in the final image is more even across the ranges.

Mastering the tones in an image is critical to improve image quality. The sliders that are discussed here are easy to use and provide instant feedback. By making small adjustments to each of these sliders, photographers will see improvements to their overall image.

*All images are courtesy of Dan Sigouin