Photographic Lighting Basics

• studio flash

• flash technology

• colour temperature

• see also:

  • Marcus Ranum's tutorials

  • Strobist's tutorials

Functions of photographic lighting:

1. to enable the photographer to see and focus on the subject, and then to create an image of the subject with a camera
2. to convey information about the subject such as shape, colour, size, texture and form
3. to comment by giving mood or atmosphere to a subject and implications of worthiness, value, happiness, misery, honesty, purity, etc.
4. to give sensual pleasure to the viewer - the "eye-candy" factor:
   • in addition to the above factors, use of lighting to modify your image will allow one to adjust image contrast and potentially simplify a confused scene by removing detail in unwanted areas by placing them in shadow or excessive brightness, or by decreasing the impact of busy multiple shadows in a scene by choosing a large light source such as a cloudy day to remove the shadows. 

What does light do to a subject?

• whenever light falls on a subject, depending on the direction of light, the size of the light source & the reflective qualities of the subject, varying degrees of each of the following parts of the subject will be present:
  • highlight:
    • this is the brightest reflection from the subject & it shows the colour and potentially the shape (eg. catchlights on the eyes) of the light source
  • highlight / lit area boundary:
    • this region shows shape & texture of shiny & semi-matte subjects
  • lit area:
    • this region shows the colour of the subject
  • shadow / lit area boundary:
    • this region shows shape & texture of semi-matte & matte subjects
  • shadow:
    • unless lit by another light source, this area shows nothing.
• direction of light:
  • the direction of light on the subject will determine how much of each of these regions are visible to the camera
  • front-lighting:
    • subject is lit by a light source near the axis of the camera
    • eg. on-camera flash
  • side-lighting:
    • subject is lit by a light source 90deg to the axis of the camera
  • half-side lighting or angled lighting:
    • light source is in a position between front lighting & side lighting
    • for portraits, 45deg horizontally and vertically from the face is often used to give a good mix of lit area showing skin tones/make-up, and boundary areas showing modelling & form, with a smaller amount of shadow area for contrast & further shaping.
  • top-lighting:
    • is just another form of side-lighting but is generally not flattering for portraits as it casts unwanted shadows in the eyes while the nose and head lighten
    • eg.  midday Summer sun
  • backlighting:
    • light aimed from behind the subject and towards the camera
    • will result in even matte surfaces gaining highlights thus backlight behind a portrait will create highlights in each hair, but those hairs will take on the hue of the light source rather than their own colour.
    • cause lens flare which lightens dark areas in the image thus reducing contrast
    • if the light source is small & directly hits the lens, it will create flare spots on the image the shape of the lens diaphragm.
    • eg. hair lights or kick lights
    • eg. contre-jour
  • thus, if you wish to emphasise the subject's colour, you need to maximise the amount of lit area such as by front lighting, but you will lose textural information
  • if you wish to emphasise form & texture, you need to maximise the area of the boundary of the lit area such as by side-lighting the subject but you will lose colour saturation
• size of light source:
  • small light source:
    • such as sun, flash gun, bare light bulb, headlights of car
    • results in sharply defined shadows, specular highlights
  • medium size light sources:
    • such as window light, photographer's soft boxes & reflectors
    • often give the most flattering portraits as softens the harsh shadows while decreasing unwanted specular highlights such as from perspiration
  • large light sources:
    • such as a cloudy day
    • results in soft shadows if any and no specular highlights & thus lacks contrast but the loss of shadows is useful for simplifying a busy scene, while contrast can be added in other ways such as by using colourful subjects (to create colour contrast) or wide dynamic range subjects (eg. blacks and whites)
• subject surface:
  • shiny surface:
    • highlight area is prominent while the lit & shadow areas tend to merge into one
    • photographer needs to consider shape, size & position of the highlights, in general, shiny objects are photographed with a medium to large light source for best effect.
  • semi-matte surface:
    • both the highlight & shadow areas are clearly distinguishable from the lit area
    • front-light or angle light to show colour and minimise shadows
    • use a small light source to reduce the size of the highlight area
  • matte surface:
    • the surface contains millions of particles reflecting light in all different directions & thus there are millions of minute highlights which are usually too small to be seen
    • the lit area shows the colour of the subject but is largely flat in appearance
    • to show texture, light it using a small to medium light source positioned so the lit area/shadow boundary is prominent.

Lighting the background:

• for an even white background using white seamless paper backdrop:
  • you need 2 to 4 lights shielded from spilling on the subject and shielded from hitting the camera lens.
  • set your lights at approximately a 45 degree angle to the background, one on each side and behind the model, off to the side so as not to flare onto the model. 
  • meter across the background and adjust until your lighting is even. 
  • Then overexpose your background by 1 1/2 - 2 stops over the lighting on the subject.
  • if you over-expose more than this, you risk causing flare around your subject.
  • if you expose less than this, you risk showing any unevenness in lighting.
•  

• an example of what would constitute a good lighting kit for the serious photographer would include:
  • 2 300-800ws strobes +/- a third strobe
  • 1 med softbox
  • 1 sm softbox
  • 1 ea reflector - gold, sliver, black, white, diffused
  • 2 large diffuser panels (could be homemade)
  • 1 spare flash tube
  • 2 spare modelling lights
  • 5 stands, 2 heavy duty (strobes), 3 light weight (reflectors, etc)
  • 2 arms or reflector holders
  • 1 pack Rosco Black Cinefoil
  • 1 set Color correction gels
  • 1 set Colored effect gels (red, blue, orange, green, yellow, etc)
  • Misc grip (gaffers tape, clamps, etc)
  • optional extras:
    • 1 egg crate for the med softbox
    • 1 set of grids (10,20,30 and 40 degree)
    • 1 wireless TX, 2 wireless RX - for wireless sync but not needed for wireless control
      • eg. "Pocket Wizard" and note that the Sekonic L-558R Dualmaster meter has a with built-in Pocket Wizard Transmitter.