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

Chapter 5: Camera, the practical side

Aperture

• Opening at the front of a camera that admits light. It is usually circular, and except in very simple cameras is variable in size, so regulating the amount of light that passes through the lens to the film.

Effective aperture

• The diameter of the beam of light that passes through the outer lens component along its axis to the aperture

• it increases or decreases proportionally as the real aperture is varied

Relative aperture

• The ratio of the focal length of the lens to the effective aperture.

• If lens has a focal length of 50mm and the effective aperture is 25mm, the relative aperture is 50/25 = 2, which commonly expressed as f number

• Larger the f number, smaller the aperture.

• Usual sequence marked on the lens barrel is

• F2, F2.8, F4, F5.6, F8, F11, F16, F22, each “stop” marking a halving of the amount of light which the aperture admits.
• F2 --> F2,8 = one stop down
• F8 --> F4 = two stops up
  

Depth of field

• Zone of acceptable sharpness extending in front of and behind the point on the subject that is exactly focused by the lens.

• if you have an infinite depth of field, it means everything that falls into the photograph is in focus, for example, landscape photographs with wide angle.
• three ways to manipulate depth of field

1. the distance of the point focused from the lens (shorter the distance, the more shallow the depth of field)
2. the size of aperture (smaller the aperture, the greater the depth of field)
3. focal length of the lens (greater the focal length, the shallower the depth of field)

Shutter

• Mechanical device used to expose film to light for exact period of time.

Shutter speed

• The period of time that allows the camera to expose to light.

Film speed

• Degree of sensitivity of an emulsion expressed numerically for purpose of exposure calculation.

ISO

• International standards organization
• sensitivity of the film or the sensors.
  
• greater the ISO number, more sensitive it is to form images in the film, yet, grainier it is.
• ISO 100 and 200, good for daytime outdoor; ISO 400 and 800, good for nighttime or indoor, or when light is insufficient; ISO 1000 - 2000, good for high speed shooting.
  

Exposure

• total amount of light reaching the light sensitive material (film) or light sensors (digital camera)
• Overexposed = too bright, the image looks washed-out
• Underexposed = too dark

Chapter 4: Understanding Light 1: Physics of light

Natural Light
Light used in photography from natural sources, for example, sunlight.

Sunlight
This is an example of natural light. This light comes from no other than our own sun. While the sun gives surely enough light for film to be exposed at, you must still do some serious thinking before taking the picture. For one thing, the time of day will affect the quality of your photo, as you will learn.

Overcast skylight
Though related to sunlight, this type of light is different in many ways. For one thing, you will not get the harsh shadows that appear in direct sun. Because clouds are blocking the sun, light is diffused, or scattered, thus softening shadows. Also, clouds can give a dramatic touch to your photos.

Artificial light
Light used in photography other than that from natural sources. Generally it refers to light specially set up by photographer such as flash or floodlight.

Diffused light
Light rays scattered, usually because of something such as fog or clouds in the way of the rays' paths

Bounce light
Light that is redirected or reflected from the light source.
If the reflecting surface is colored, the it will affect the color of the light, thus, white surfaces should be used for bounced light unless special color effects are desired.

Bounced flash
Technique of softening the light from a flash source by directing it on to a ceiling, wall, board or similar reflective surface before it reaches the subject. The light is diffused at the reflecting surface, and there is a decrease in light power because of absorption there and because of the greater distance between light source and subject. Bounce flash is particularly used in portraiture, where direct flash is often too harsh and unflattering and can cause red-eye.

Chapter 3: Photocomposition

Photocomposition
Golden ratio
• 1:1.618

• if you divide each smaller window again with the same ratio and joining their corners you end up with a logarithmic spiral. This spiral is a motif found frequently throughout nature and shell, horns and flowers.

• the golden mean and the phi occurs frequently in nature and it may be that humans are genetically programmed to recognize the ratio as being pleasing.



The rule of thirds

• where a picture is divided into three sections vertically and horizontally and lines and points of intersection represent places to position visual elements.


Lines & Implied forms
Vertical lines = emphasize the power, strength, and height



Horizontal lines = express stability and width



Diagonal = express dynamite energy



Curving lines = expressed sensuality



The Curve
• Here is a line of great beauty and charm and nothing gives a better example than a beautiful female form with all it’s lines and curves. Of course there are other examples: the curve in a river or a pathway through a flower garden.

The “S” curve
• This line goes further than just a plain curve line. It is called the “line of beauty”. It is elastic, variable and combines charm and strength. It has perfect grace and perfect balance. You have seen this “s” curve hundred times in drawing and paintings and other works of art.

The leading line
• The lines that leads your eyes in to the picture area easily like a road or a fence, a shoreline or river, a raw of trees or pathway. A successful “leading line” will lead your eyes into the picture and take it right to the main subject or center of interest.
• An “un-successful leading line” will take the eye in to the picture but will zoom the eye right out of the picture if there is no stopper to hold the eye in the picture frame; such as a tree, house or rather large object on right hand side of the picture frame which will stop the eye going out of the picture. The center of the main subject will act as a stopper and hold the eye in the picture frame.
• The best leading lines will start at lower left area of the picture frame but not in the exact corner. Again, the eye likes to enter a picture frame of this point and leading line will help it get in to the picture easily and swiftly.
Implied forms
• Combination of implied lines and they help to hold a picture together. Eye enjoys these interesting forms and will stay in the picture area to examine each one of them, if they are present.

The circles
• Is made up of continuous “curve” and it’s circular movement keeps the eye in the picture frame. There are many circles in nature and man made objects and if you find them in an image before you, be sure to make good use of them in your photography.

The triangle or pyramid
• This has a solid base and will show stability. It also has height and strength. The pyramids of Egypt have survived for thousand of years while other types of solid buildings have crumbled into dust in less time.
• A triangle can show up in your viewfinder as three points in the scene, such as two trees on the grounds pointing to a cloud in the sky. Sometimes a fence in combination with stream and a farmhouse can form the triangle composition

The Radii
• Is a connection of lines meeting in the center and it is also an expansion of lines leaving the center.

The Cross
• A showing of “opposing force” that will give the picture a feeling of cohesion and relationship. The horizontal bar of the cross will act as a “stopper” while the vertical pole can act as leading line. The windows in a large skyscraperwill form crosses and will keep your interest in the building
• Could relate to religious meaning.

The “L” or rectangle
• This makes an attractive “frame” it can be used to accentuate important subjects. Many times it is a frame within a frame.

Mass
• Equal objects, such as trees, houses, mountains, lakes or any other large or small object with in the picture area.
• Two sections, formal balance and informal balance

Formal balance
• Sometimes called equal balance or classical balance. It elicits feelings of dignity and repose but makes static, unimaginative photo images as the objects in the picture area are of equal size, one balancing the other equally like two children of equal size on a playground seesaw.
• Looks boring unless you have definite reason to use it.

Informal balance
• Gives an unequal balance in the picture area. If you have a large object in the picture it should be counter-balanced with a smaller object or objects to make good photocomposition.

Bull’s eye composition
• “No, No” in good photocomposition. When you place the main subject right “smack” in the center of the picture area it is called bull’s eye. This should be avoided at all times, unless you have definite reason for doing it.
• With main subject at the center of the picture frame the eye will go into the picture and stay in the center, eyes will not move around to enjoy the rest of the picture. Eyes can get tired very fast and lose interest of the photograph.
• Even the object is a little off center, it can still improve the picture’s composition.