What type of illumination is recommended for photographing external eye structures?

Diffuse illumination is recommended for photographing external eye structures because it provides a softer, even light that minimizes harsh shadows and highlights. This type of lighting is crucial in ocular photography, as it allows for better visualization of details without the risk of glare that can obscure delicate features of the eye. By distributing light more evenly across the subject, diffuse illumination enhances the clarity and quality of the images captured, which is essential for accurate assessment and documentation of the eye's external anatomy.

Moreover, this technique can help reduce the potential for reflections that are often problematic when using direct lighting, resulting in clearer and more informative photographs. Proper lighting is vital for various medical evaluations and photography, and the use of diffuse illumination supports these needs effectively.