With digital cameras becoming more and more common,
it's getting easier and easier to get images into the computer for
retouching. We'll look at correcting "red eye" in this column.
This candid snapshot of the notorious Young Johnny G is an extreme
example of "red eye." Red eye occurs when light reflects off of
the capillaries in the back of the eye. The capillaries, filled
with blood, reflect red (unless, I suppose, you have an image of
a true "Blue Blood"). Typically this happens when the flash is directly
above the lens and the subject is looking into the camera. ("Look
at the birdie!") In this first example, the pupils are dilated far
enough to reflect from an angle.
Let's zoom in and apply two different techniques. On the left
(Johnny's right eye), you'll see the result when the pupil is
filled with black. It looks as unnatural as the red eye. On the
right, the pupil has been adjusted using the Paintbrush, set to
60% opacity and a blending mode of Luminosity. This leaves the
natural reflections and specular highlights. (Specular highlights
are explained below). This produces a more realistic image. Note
that the pupil hasn't been changed all the way to black. There
is still a hint of a tint, which adds to the realism.
Another, more typical, example of red eye is seen
below. The Lovely Libby was looking directly at the camera when
the flash and shutter cycled. The fact that the eyes match the
dress does, in this case, ruin an otherwise beautiful photo.
In this case, the red eye reduction technique most
appropriate is desaturation. The Sponge tool, set to Desaturate
and Pressure at 50%, makes quick and easy work of the pupils.
The brown eyes are emphasized, with natural highlights.
One more example shows Perry O. with his Dad. (Hmmmm...Dad
doesn't have red eye -- could it come from the mother's side?)
In this case we'll use a technique that is appropriate
for critical projects and high resolution images. A selection
is made of the reddish areas of Perry's eyes. The area includes
the entire pupil, with the specular highlights. To eliminate the
red, use Image> Adjust> Selective Color. With the pop-up menu
set to Red, click the radio button for Absolute, and increase
the amount of black using the lowest slider.
Specular Highlights
Specular highlights are those reflections in a photograph that
contain no color information. Their RGB values are 255/255/255.
Such pure white areas are natural and removing them completely
is usually unnecessary (and sometimes results in an unnatural
look). The word "specular" refers to mirror-like reflections.
And, of course, a white light source reflected in a mirror produces
white.
New at Adobe's Web site is the Photoshop Expert
Center. Tips & tutorials, updaters, plug-ins, downloadable Goodies,
and training resources are just some of the things available to
you on these pages. Check it out at www.adobe.com