"Tonality Tuning": brightness and contrast to order

Mittwoch, 23. Januar 2008, 21:08

> Deutsche Version

The fine tuning of brightness and contrast in photographs is an exercise that requires a good deal of sensitivity. The smallest changes can make the difference between an outstanding and an average photo. As in most cases, the photographer himself is usually his own harshest critic.

There are various ways of adjusting brightness and contrast in Photoshop, but even with the required expertise, finer and more precise adjustments require time and patience.


What improvements does the photo need?

If you have a lot of photos to process, a simpler method (for example the Auto function in Adobe Camera RAW; "brightness/contrast" or "levels") will probably save some time. For those with more precise demands, individual processing might be preferable, always with the question "what improvements does the photo need?" in mind. In many cases, the answer is simple: "lighter shadows", "more contrast in the mid-tones" or "reduced brightness in the light tones".

The classic tool for this purpose in Photoshop is the gradation curve applied as adjustment layer, with which adjustments can be made with high precision - provided that one is willing to invest the time and to try out and compare different settings. There is often the added difficulty that the optimisation of one area of tonality can affect other areas that do not need modification. The solution is the layer mask which confines adjustments to a defined area or tonality range of the image. These masks can also be drawn manually with the paintbrush or - in the form of luminance masks - created from the brightness information of the image channels. Working with the paintbrush is a question of intuition: it is quick but not very precise. Luminance masks are a more exact solution but they are difficult to generate and usually require a considerable amount of post-editing.


Tonality Tuning: time-saving and flexible

A flexible and time-saving solution is offered by Uwe and Bettina Steinmueller from Digital Outback Photo (DOP) with their Photoshop script "Tonality Tuning".

Instead of creating gradation curves and layer masks yourself, Tonality Tuning has a practical interface for the selection of brightness and contrast settings. Using the mouse, a preset gradation curve (adjustment layer) is then created for the required adjustments with a layer (luminance) mask, which can be fine-tuned afterwards if necessary. In this way, light tones, mid-tones and shadows can be modified quickly and extremely accurately. The strength of the effect can be regulated by way of the layer coverage. If the effect is too weak, the layer is simply duplicated.

Alternatively, it is possible with Tonality Tuning to select areas of brightness and store the selection, for example, as an alpha channel for further processing. Or else an adjustment layer can be created from the selection (see "Workflow with Tonality Tuning" below) and the changes confined to shadows, mid-tones or light tones alone.


Smart and congenial

Tonality Tuning is one of those smart yet congenial add-on tools for Photoshop that makes expert knowledge directly available for image processing. Instead of having to learn a new program, the tool can be set to carry out all settings in Photoshop automatically from within the familiar software environment. Further adjustments can then be made with the (powerful) functions in Photoshop - in the case of Tonality Tuning with layers and layer masks.

Highly recommended!



Workflow with Tonality Tuning

Basic settings for brightness and contrast control - here I
have selected "mid-tones brighter".

The mid-tones are now somewhat brighter. Tonality Tuning
creates a gradation curve in Photoshop with a layer mask
for the required adjustments.

Alternative: selection of an area with Tonality Tuning and
subsequent creation of an adjustment layer in Photoshop
(here the mid-tones were strikingly altered with
"hue/saturation").