7.8 Dealing with Red-eye and Steel-eye

Like human eyes, bird eyes can sometimes show unpleasant reflections from the inner eye when using flash photography.  In humans, the red eye effect occurs when blood vessels in the back of the eye reflect red light back to the camera.  In birds, a more common effect is steel eye, which appears as a bluish-white reflection, again from the back of the bird’s eye (many birds have a reflective layer of cells in the back of their eye, possibly to improve light collection by their cones and rods in dim environments).
    There are basically two ways to deal with the problem of 
eye shine (red eye and steel-eye).  The first is to prevent it from happening in the first place (or, at least, reduce its incidence) by raising the flash unit above the camera via use of an off-shoe cord and a flash bracket.  The figure below illustrates this approach.

Fig. 7.8.1 : Raising the level of the flash unit can reduce the incidence of eye-shine.
This requires the use of a flash bracket and an off-shoe cord.  Depending on your
setup, it may be easier to just remove any eye-shine later in Photoshop.

The flash units in this case are mounted on a special bracket which attaches to the tripod head.  These flash brackets typically run $100 to $200 (US), and you have to find the right model of bracket for your particular tripod head.  If you’re using the popular Wimberley gimbal-type head, finding a flash brack should be easy.  For other heads, there may or may not be a commercial flash brack available that will attach directly to your tripod head.  Some flash brackets can attach directly to your camera via the screw hole in the bottom of your camera body; I’ve never seen this type used in the field.
    Attaching the flash unit to the camera requires the purchase of a special off-shoe cord (one of the curly cords shown in the figure above).  These typically cost about $30 to $60 (US).  Note that some of the cheaper cords have a reputation for breaking easily, or for spontaneously detaching: on a recent trip I saw a flash head detach from its off-shoe cord and fall onto a hard surface (it was not damaged by the fall, but could have been, and the owner was definitely not happy about the incident).
    My personal preference is to keep the flash unit mounted directly on the camera (since this allows easier use of larger, home-made flash extenders—see section 7.9) and to then manually remove any eye-shine in Photoshop.  For those birds having completely black eyes, it’s a simple matter to paint away the eye-shine using a digital black brush in software.  Unfortunately, this leaves the eyes looking dead.  Using a tiny (digital) brush you can then add in a
catchlight—a small pinpoint of light—as illustrated in the series of images below.

Fig. 7.8.2 : Removing eye-shine and replacing it with a catchlight.  Top: this owl
chick exhibited red-eye when photographed with flash.  Middle: painting out the
red-eye in Photoshop is easy, but results in dead-looking eyes.  Bottom: painting
a tiny white
catchlight in the 2 o'clock or 10 o'clock position can restore
some degree of dimensionality to the eyes, though finding exactly the right
location for the catchlight can be surprisingly difficult.

A catchlight is a natural effect that occurs in direct sunlight and makes the eye look more natural by conveying information about the curvature of the outer eye.  Natural catchlights can occur as simple points of light like those shown in the eagle photo below, or they can be larger and more complex.  Methods for adding artificial catchlights via software are discussed in Chapter 11.

Fig. 7.8.3 : Flash can create its own catchlight.  In this case, the twin catchlights
help to reinforce the impression that the bird is staring at the viewer.

I find that many times the catchlight created by the flash makes the bird’s eyes look more alive than if I hadn’t used the flash.  The times when it instead creates an unpleasant eye shine that I have to fix in Photoshop are, in my opinion, a reasonable price to pay for the many advantages of using flash for bird photography.