Specular Highlights

The next exploration of aspects of lighting on http://www.strobist.com/ is concerned with the control of specular highlights. That sounds flash doesn't it (no pun intended). This is just the technical term for the usually blown out bright spot on a subject that is the direct reflection of the light source.

The first example image demonstrates this phenomenon rather crudely. The flash umbrella used as the light source is clearly visible in three three spoons. This shows how different apparent light sizes could be used to create a slightly different effect. the other feature of this image is the usually undesirable reflection of the photographer and camera. The on camera flash is visible even though it was set to not trigger. The reason for this is that I am using the Nikon CLS system to trigger the off camera flash. The on camera flash cannot emit the infra red signal without a tiny amount of visible light. Normally this would not supply any discernible light to the scene. The case of a direct reflection is an exception.

The second image is better in one respect. Altering the camera to subject angle has eliminated the photographer's reflection. the spoon shape is quite tricky for managing reflections, with a flat subject it would be easier to visualise when the specular highlight will appear in the image. The third spoon image shows the spoons positioned so that the top spoon has no specular highlight, the second a tiny and the third some more. That ugly photographer is back though! Also of note in this image is the white bar which is a reflection of the edge of the plate on which the spoons are resting. The possibilities are limitless, the challenge is taking control of the variables.

The last two images in this post are not included to illustrate anything about specular highlights

but they do quite nicely show the usefulness of a tiny amount of on camera flash to fill in a shadow side of a subject. This coffee pot is a potential nightmare of unwanted reflections. The first shot is taken with just a large translucent umbrella to the right. There is a fairly deep shadow on the left of the pot. A small amount of on camera light has reduced this. The final result is an evenly lit coffee pot with definition between the many different surfaces. The rim and spout are catching the light nicely to show the subject shape.

I must be honest, this is not the sort of photography I normally enjoy but I feel that I am learning so much by playing with these inanimate objects. A human subject would not tolerate this amount of experimentation.