If you've never heard of this term, or perhaps have, but had no idea with that the photographer was referring to, then the next five minutes should be very enlightening (no pun - ok - a little pun intended there) for you.  Capturing catchlights is very popular technique in portraiture and for good reason! A catch light is a spark of light in your subject’s eyes. This spark will help draw the viewer’s attention to your subject’s eyes making them full of life and, well, sparkling.

Technically speaking a catchlight is a light source that causes a specular highlight (something super shiny) in the subject's eyes in an image and they can be created a number of ways.  The absence of them can really drag a portrait down, making it dull and lifeless.  

Look at the images of Sula below; because she's a black dog and we photographed her with low-key lighting, we really need to see both of her eyes and in this pose there's barely a wisp of a catchlight in her camera-right eye. She looks like a pirate! But with a slight turn of her head toward the light, bingo!  We've got bright eyes popping in this black dog against a dark gray background. Image how lifeless this image would look if we didn't have catchlights in her eyes?  

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