Four Characteristic of Light for Photography
  1. At any fixed distance, the large the light source, the softer its illumination. Penumbra(softer light) between highlight and shadow.

  • L1 and L2 are light sources.
  • B=Penumbra(light between the highlight and shadow)
  • A=Umbra(shadow)

2. With any light of a given size, the closer it is to your subject the softer its illumination. No matter how big and how small the light source is, when you put it closer to the subject, the light will become softer.

3. Inverse Square Law. alway keep this is mind, then you could find out how the light change.

4. Direct light is more intense than diffuse light.

Quality of Light

  1. Direct light – light source to the object directly, is has more intense light. Direct light usually uses in highlight.
  2. Reflected light is softer light. Reflected light has greater umbra. the more umbra area you get, the object has more texture.
  3. Diffused light- from the light source to the object, its light is soft. you can use some kind of transparent matter(plastic, paper, etc) and put it in front of the strong light source, then you can get a diffused light.
  4. Radiant- it happens when light directly into the camera lens.


  • Texture
  • Volume
  • Highlight
  • Shadow

different light direction creates a different texture, volume, highlight, shadow. Side light, top light, bottom light, front light, and backlight could create contrast and volume, highlight and shadow, and texture of the object. there is one thing of the backlight is different from others. backlight create an outline of the object, the others don’t.


edited by Jm

Different color of light is a way to show emotion. when the light is too yellow, you can use the opposite color to keep the white balance.