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T436 - Fall 2012 - Week 4

Readings: Blain Brown, chapters 10, 11, 12 & 13. Watch DVD chapters on lighting and gripology.

Agenda/Reality check:

  • Cinema technique reports this week: Mark & Brian
  • This week is devoted to lighting. Lab this week: Lighting exercise – bring gray card and light meter if you have one. Please think about how you would apply the Zone System to light a scene. You'll be carrying out a camera rating and lighting exercise. Please note the PDF of the Sekonic L-558 instruction manual that's on our website.
  • We'll continue working on the production schedule and various roles. If there is something you want to do, please let me know (via email if possible).
  • Don't bring gear back late - or expect the Prod Lab People to stay late for you.
  • Note: We've got just two more labs devoted to learning techniques and practice. After that it's all production. We can still learn new techniques and cover new material- but only in lecture.
  • Jibs and sliders this week in lab as well
  • Maybe one bonus week for planning?

Lighting (continued)

Review from chapter 7:

Know the difference between upstage verses downstage lighting (similar to narrow vs broad). In upstage lighting the key is upstage of the camera (just like in narrow lighting - the key is on the opposite side from the camera).

Practicals - Real life lighting instruments appearing on set. They are best used with a dimmer.

According to the fabulous DP Michael Minnock, all objects must do 2 out of 3 things:

  • reflect
  • absorb
  • transmit

Lighting people and spaces (Zone system & pools of light)

High key lighting – low contrast lighting used in sitcoms. Feels light
Low key lighting – High contrast lighting used for a more dramatic effect (X-Files)

Getting the mood across is a combination of lighting, composition, camera, blocking, and acting. But lighting generally plays a key role in establishing mood. Consider the following questions:

How would you make something or someone scary or tense?
How would you make something happy or light?
How do you make a scene feel intimate or sensual?

There are certainly lighting techniques - low key lighting for scary. Low angle. Pools of darkness. One could use high key lighting for lightness. It's a combination of elements. Character, story point, character arc in relation to story line. Music, cutting, framing of shots. Lighting is only one element.

Get them all to work together and you have something.


Exposure (chapter 10) ------------------------------------------

Four Elements of Exposure:

  1. Amount of light
  2. Aperture (iris/f-stop)
  3. Shutter speed (usually 1/60th of a second for 60i/1080i video)
  4. ASA/ISO

For video, it's always better to underexpose a little rather than to overexpose a little. (But try to make it perfect.)


F-stops show a ratio of focal length to diameter

  • Going up one whole stop (E.g. f2 - f2.8) halves the amount of light coming into the lens
  • Going down one whole f-stop (E.g. f2 - f1.4) doubles the amount of light

In other words, changing by one whole f-stop changes by a factor of 2 (or 1/2).

whole f-stop












1/3 f-stops























An f-stop of 1 is the largest opening one could theoretically have.

Focal length review:

Focal length = distance from optic center (or principle plane) to target (or corresponding focal plane)

f-stop = focal length / diameter of lens

Zone System

The Zone System provides a good way to plan lighting for a scene. The book has an excellent example on page 204. Here's another (on-line) example: http://f164.com/the-zone-system-for-digital/10/2011/


Lighting & Light Meters

Incident vs. Reflected light

Incident light is measured from the source. Most light meters have domes used to measure incident light. One would stand where the subject is and aim the meter at the lighting device to measure it.

For photographers, reflected light values are usually more useful. These measurements are taken off of the subject. In a light meter's spot metering mode (available on the Sekonic L-558), we are measuring reflected values. Reflected light meters assume they are looking at an 18% gray card.

18% gray card – incident equals the reflected amount.

  • ASA stands for American National Standards Institute or American Standards Association. It's an older standard now mostly replaced by ISO.
  • ISO stands for International Organization for Standardization or International Standards Organization

On using the Sekonic L-558:

  • Make sure you're in the right measuring mode (Cine Mode / shutter speed priority mode / ambient light). You should see a sun icon in the top, left-hand corner surrounded by a square. You also need to see either a T below the battery icon surrounded by a square or a "f/s" which is frames per second. To change the mode, press and hold the mode button in while turning the jog wheel.
  • Next be sure you're shutter speed is set right. For 1080i (30 frames per second), we need to make sure the f/s shutter speed value set to 30. (It will really give use 1/60th of a second, which is the duration of one video field. Cine meters like the L-558 assume a 180 degree shutter value.)
  • Make sure you're in the desired metering mode (spot reflected or incident) by turning the eyepiece/dial on the right hand side. The selected mode will show in the LCD display.

Notes on the Sekonic L-558 display:

  • Make sure you understand the large f-stop value. It is followed by a single digit (10th of an f-stop). This value is represented graphically at the bottom of the LCD display.
  • The pair of numbers directly to the right of the f-stop number value is compensation. Unless you are compensating for something (like a different shutter angle, etc.) it should read [00]. When you are compensating the appropriate +/- icon will be displayed.

Sekonic L-558 manual (PDF)

Sekonic’s light meter faq:


Inverse square law

The inverse square law applies to sound, gravity, and point source light (energy that radiates). In other words, it doesn’t apply to laser beams. It works best with a bare candle or bulb radiating light evenly in all directions.

Point source light's intensity is inversely proportional to the square of the distance

Assume a light casts a quantity of 100 footcandles at 10 feet

  • At 20 feet it will cast 25 footcandles (100/2x2 or 100/4)
  • At 30 feet it will cast 11.11 footcandles (100/3x3 or 100/9)
  • At 40 feet it will cast 6.25 footcandles (100/4x4 or 100/16)
  • At 50 feet it will cast 4 footcandles (100/5x5 or 100/25)

There's a good explanation of the inverse square law at:

Inverse Square Fun with the light meter:

You can test the inverse square law yourself using the Sekonic L-558. To do so, use a point source light (E.g. bare bulb) and setup the Sekonic to function in incident mode (page 26 of the manual):

  • Turn the Lumisphere retracting ring q to lower it to the mark position.
  • Make sure that any compensation (see page 28) is canceled.
  • Set the meter to EV mode and ISO 100.
  • Place meter parallel to the subject and take a measurement 1 foot from the light source.
  • Now move back a foot and take another reading. It should be about 1/4 of the first reading.
  • Move back another foot (3 feet away). Your reading should be about 1/9 of the original reading.


Zone System

The Zone System is useful for objectively and accurately designing and analyzing lighting setups.

Understanding how to use the zone system is key to lighting scenes. While we can have as many zones as we want in a zone system, let's use 10, as this is a good number to use for video. On a waveform monitor, digital black is 0 IRE. The brightest white is 100 IRE.

Pure black is Zone 0
The brightest white is Zone 10
Anything over Zone 10 is overexposed



(18% reflectance) On a waveform monitor, this is about 55 IRE


Camera Movement (chapter 11)

Be sure you know the various types of camera moves and what they accomplish

  • Punch-In (Camera stays put and a longer lens is used)
  • Tracking (Camera moves with subject)
  • Countermove (camera moves in opposite direction of subject. The background can move twice as fast)
  • Reveal (Camera moves to reveal NEW CONTENT)
  • Circle (You can figure this one out)
  • Crane/jib moves (Allows camera to move up and sideways. These are great for opening and closing master shots in scenes. "Ameilie" has some wonderful examples of this.)

Mounting devices:


Types of Camera Heads:

  • Fluid head
  • Geared Head
  • Remote Head (like on our jib)
  • Friction Head (not used much)
  • Underslung Head

High Hat - Low to gound mount



Motion Control (Good examples include Michel Gondry's Kylie Minogue video "Come into My World" (with some awesome difference keying and layering) or clips from Amelie)

Chapter 12 color

Know the two color systems (additive/RGB and subtractive/CMYK) and what they are used for.

Know the two basic compensation gels: CTO (color temperature orange) and CTB (color temperature blue) and what they are used for.

Chapter 13 image control


Can be round, square or rectangular
Square are usually used with a matte box
Round filters can be directly attached to the lens

Filter Types

  • Color compensation & correction (light-balancing filters, warming, cooling, etc.)
  • NDs (reduce exposure without affecting color temperature)
  • IR (reduces infrared light)
  • Graduated (Color grad, ND grad, etc.)
  • Diffusion (soften an image)
  • Polarizing (can reduce light from a specific direction)
  • Special Effects (E.g. 4-point star)

Always think in terms of f-stops and how you are affecting them.


Every 3 db of gain is 1/2 of a stop. 6 db of gain is a whole stop.

ND filters*


ND .3

ND .6

ND .9

ND 1.2

Takes off (in f-stops)





reduction of light (in %)





* Tiffen website: ND filters

Polarizing filters take of 1.5 to 2 stops

CTB gels can take off 75% of a lamp's output.

Scrims (the type that slide into a light's filter frame) come in singles and doubles. Singles take off a half a stop, doubles take off a whole stop.

ND filters


ND .3

ND .6

ND .9

ND 1.2

Takes off (in f-stops)





reduction of light (in %)





Polarizing filters take of 1.5 to 2 stops

Problem Solving:

You are on the beach on an overcast day. You need to shoot some video of someone walking along the shore. You want to use a 100mm lens at f-2 in order to have the proper depth of field and angle of view. However your light meter tells you that you ought to be shooting at f-4. What should you do?

Solution: You need to figure out the difference between the actual reading and the desired f-stop. The difference between f-2 and f-4 is 2 f-stops. Therefore if you used an ND filter of .6, it would take off two stops.

Misc. Filter info links:


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