Chapter 6: Understanding light 2: Studio lighting

When used in portrait photography, the term “Key” refers to the overall tone of the final photograph. The elements of the portrait that play into the tone of it are the color of the background, the color of clothing used and the color of any props or foreground elements.

Generally, portraits are classified in one of three keys – low key, mid key or high key.

Low key portraits are created using a dark background and dark clothing and props. You can identify the key of a portrait by determining the average tone for the scene.

• more dark elements than bright ones
  
• Clothing and background might be black or dark browns giving the feeling of drama or rigidity.
  
• higher lighting ratio near 3:1(or higher about 8:1), which means, big contrast between highlights and shadows.
  
• Shadow takes over the subject, that a lot of details are gone.
  
• Usually only one key light is enough, or sometimes accompanied with very soft fill light or simply a reflector.
  

A high key portrait setup would involve the use of a white or off white background and brighter clothing.

• it requires a great deal of light control and has the most risk of overexposure and loss of detail.
  
• low lighting ratio near 2:1 to 1:1. In other words, there’s not much contrast between highlights and shadows on the subject
  
• A common background for high key portraits is paper which is slightly overexposed resulting in a pure white seamless background and a feeling of cleanliness.
  
• Great care is usually taken to separate the subject from the background to eliminate shadows.
• These portraits also tend to require more light and thus more power and lighting equipment to create.

mid key portraits will use skin tone to set the mood. In these cases, clothing may be used to accent the tone of the skin with contrast rather than allow all elements to blend together.

• Often a high key portrait can be converted to a middle key portrait by reducing exposure.
  
• Often the background sets the tone for the image and as such key should be a consideration at the beginning of a portrait setup.
  
• A background should not take focus off of the subject, but rather help lead the eye to the subject in the final image.
  
• Take time to identify your overall tone, or key before you arrange the lighting setup and you will be surprised at the results.
  
• Lighting ratio is about 2:1. Shadows and highlights are well balanced. The details are all preserved, and fill light is normally required.

3-point-lighting

key light

• main source light.
• stronger the light darker the shadow
  

fill light

• it's used to fill in the shadows created by the key light

Back light

• It creates a rim of light surrounding the model/subject that separates him/her/it from the background.
  
• It adds three dimensionality to the picture.
  
• it's set above or behind the model.
• It can be in high or low intensity, if it's in low intensity, we usually refer it as hair or head light.
  

Head light/hair light

• to give some highlight on the model's hair, to give his/her hair some details.

*let's clear up some confusion here. yes, back light, head light and hair light may be very similar, the differences are the intentions. Back light is to separate the model from the background by creating a rim of light around him/her. However, head light and hair light are usually in low intensity, and the intention is to have a nice shine on the hair. got it?

This is a youtube video about basic studio lighting. if you are interested, you can check it out. It's very informative and he mentioned a lot of tips that I couldn't cover during class.

http://youtube.com/watch?v=6lsRu90jE88
http://youtube.com/watch?v=9crGU-QRCZE
http://youtube.com/watch?v=VUJ_nV4UXcQ
http://youtube.com/watch?v=eMY_uWZRNEg
http://youtube.com/watch?v=B4PK7gddT_s
http://youtube.com/watch?v=sJugEUrqCH4
http://youtube.com/watch?v=t49wbabsM5E
http://youtube.com/watch?v=9oFWgGIWRRM