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Dogs, Pillars and Glitter Paths ~ Kiri Stuart-Clarke ( photography ) imaged this scene at Hunstanton, Norfolk, England.    Image©Kiri Stuart-Clarke
Sunlight reflects off a wavy sea in many directions but there is still order.

Often the reflections form caustics, sheets of intense light which appear to the eye placed as at left as a dazzling point dancing over the sea surface. When intersected by a boat hull they form ever changing spidery patterns.

From further away the many caustics from many waves merge into a glitter path.

Sundog rays are simple by comparison. rays enter a plate crystal side face and leave through another inclined at 60° to it. Unless the sun is on the horizon, the ray also reflects internally (not shown at left) an even number of times from the near horizontal upper and lower faces.

Glitter Paths

The light of a cloud curdled sun reflects in gentle North sea undulations to form a glitter path bent at its base by shore induced wave asymmetry.


Mirrors in the clouds – horizontal plate habit ice crystals – imitate the glitter as a pillar pretending to beam upwards from the sun.


More plate crystals refract and disperse sunlight into a prismatic sundog. At its closest, 22° from its master when he is setting and on a wider leash when he is higher. Rays through the ice prisms reflect too in the waves to form a second glitter path.   A glitter dog?