GUIDE TO SHOOTING RAW PART III

COLOUR CONTROL

 

ALTHOUGH you can use the Curves and Levels tools to adjust the overall contrast of the image, to get the most from the colours in your picture you need to use the dedicated controls that are available Whether it's global adjustments in the form of vibrancy or saturation, or individual colour control, the changes can have a significant effect on your image Also, in raw format they are made using the full colour gamut of the camera so greater control's available.

SATURATION

The Saturation control is usually in the form of a slider that allows you to alter the colour saturation of your image By removing all saturation you create a black & white image, while boosting the saturation will make the prominent colours brighter and more intensive This is a handy tool for landscapes when you want to boost the blues and greens in one simple step, and it can quickly add punch to an overcast scene You can also reduce the saturation slightly for a more muted colour effect, such as with a portrait.

VIBRANCE

Where Saturation provides colour adjustment in a linear form (increasing all colours equally), the Vibrance control takes a non-linear form, boosting subtle colours more than the prominent ones This will result in a more natural increase in saturation that appears evenly across the scene and Is more suited to equalising colours and for shots with subtle gradation. By combining the effects of the Vibrance and Saturation sliders, it is possible to achieve a great deal of control.

COLOUR SPACE

IN THE same way as a camera's tonal data is restricted when saving a JPEG, so too is its colour range. Most cameras offer a choice of sRGB or Adobe (1998) RGB colour spaces, depending on the required use for the file (usually sRGB for screen display and Adobe RGB for printed work). However, the colour space of the sensor generally captures more information in some areas than is contained in ether of these selections, so data is removed in the processing. Raw files maintain the full colour space of the camera and will only restrict this to sRGB or Adobe RGB when processed in software This means there is more colour to use in the adjustments.

HUE, SATURATION AND LUMINANCE

The Hue, Saturaton and Luminance controls are the equivalent of your Colour Mixer palette in the raw converter and appear in most advanced versions of software, including Adobe Lightroom and Photoshop's Camera Raw plug-in. They allow individual control of all your main colours, from red, green, yellow and blue through to orange, purple, aqua, and magenta. Each colour can be adjusted individually via the Hue, Saturation or Luminance controls The Hue setting is useful for changing the appearance of a colour that may have been affected by the lighting. For instance, you can make a pink dress appear redder or a murky lake appear bluer The Saturation control works in a similar way to the global saturation slider but applies to just the selected colour, boosting its appearance in the scene. Finally, Luminance brightens or darkens the appearance of the colour.

COMBINATIONS FOR EFFECTS

By adjusting multiple sliders, it 5 possible to make more creative adjustments to the colours For instance, a cross-processed look can be achieved by reducing the Hue and increasing the Saturation in the reds, yellows and purples, combined with some split-tone adjustment (see below) A polarising effect can also be achieved, or enhanced, by increasing the Saturation and decreasing the Luminance in the blues.

SPLIT TONING

The Split Toning palette in Lightroom and Camera Raw allows you to use different colour casts for shadows and highlights by adjusting the Hue and Saturation for each This can be used to create duotone images from black & white conversions or to add casts to colour images for effects such as a cross-processed look

BLACK & WHITE

Converting an image to mono through a raw file allows the greatest amount of control due to the larger range of tones available. In Lightroom and Camera Raw. the full collection of colour sliders can be used to create the greyscale mix in the same way as you would use the Channel Mixer in Photoshop The colour sliders work in a similar way to filters, and by increasing or decreasing combinations of sliders you can darken or lighten certain tones within the image to create the desired black & white effect