Although the principle of reflection is applicable to all the wavelengths in the electromagnetic spectrum; as photographers we are only concerned about the reflection of light. Reflection is nothing but light bouncing back off the surface of any object.
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| Reflection of Light |
Law of reflection says that the angle of reflection will always be the same as the angle of incidence (angle at which light falls on the surface). There are mainly two types of reflections as far as light is concerned first is specular reflection in which most of the light falling on the surface is reflected back and the second is diffuse reflection where only a portion of light falling on the surface is reflected back.
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| Angle of Reflection of Light - Source Wikipedia |
Important Note: Polarizing filters, every photographers trusted alley to control reflections work only in sunlight, they do not work to control reflections with studio lights unless polarizing gels are fitted on.
Specular reflection Vs Diffuse reflection
Specular reflection occurs from smooth surfaces such as mirrors or a calm water body. Diffuse reflection occurs off surfaces with a matt finish such as paper, clothing etc.
Specular reflection produces a reflected image of its surroundings (inversed exact replica) on its surface where as diffuse reflection does not produce a clear image but instead allows you to see what is on the surface.
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| Photo By Chris Gin |
There are a variety of reflectors used in photography to reflect light on to the subject or scene. Depending upon the surface texture or smoothness they produce light quality from specular to diffuse in varying degrees. In photography it is easier to photograph subjects with surfaces that give diffuse reflections as the subject does not reflect back an image of the camera, the photographer, lights etc. But an object with surface giving out specular reflections will reflect everything and so special care and special techniques (such as the use of a light tent) are used when photographing them.
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| Specular Reflection Angle - Source Wikipedia |
One classic example of subject with specular reflection that is hard to photograph is glassware. Glassware could be either transparent or translucent and are highly reflective. Special equipments like long strip lights, black bounces, etc are employed to avoid unwanted reflections and to use the reflections that are present in an aesthetically pleasing way.
In the next article we will discuss about Quality Of Light - Diffusion
In the next article we will discuss about Quality Of Light - Diffusion
