T351 Week 7 - Fall 2015
- Midterm Exam Next Week!
- Don't forget to stay on top of the readings! This week they are: Cybercollege units 27, 28, 29, 30, 31, 32, & 34.
- Audio/News Exercise:
- Due by start of lab this week. Please keep these as succinct as possible.
- If you aren't turning in written releases, be sure to tag the on-camera releases onto the end of your video( a few seconds after it's dipped to black).
- Turn your assignment in via a shared IUBox folder, saved as your username. (Mine would be "jarkraus") Please send links to both Keith & myself.
- Turn your critique in via Oncourse, to the Audio/News folder.
- Interview / feature story: There is no lab next week to give you time to produce your Interview/Feature Stories. We'll
watch and critique them the week after next.
- Next week your Art Video proposals and treatments are due by the start of your lab time next week. Please upload a copy of your materials to Oncourse/Resources/Art Video folder.
- Midterm Quiz in two weeks! We'll review for it next week.
- Your final project proposal will be due in two weeks.
- Please also think about your short stories / dramatic scenes.
The pre-production materials for the scene are due in three weeks. We'll pitch these in lab the week before spring break.
Share techniques with lighting for portraiture, fashion, painting.
Unlike the flash photography used for still photography, video requires "constant on" lighting.
Lighting can be thought of in terms of
- Quality (coherence) - Hard vs. Soft
- Color temperature (color)
- Intensity (brightness)
Lighting instruments can be broken down into two major types: spotlights
and floodlights. In general, spotlights produce focused beams of light
(hard light) whereas floodlights create softer, more diffused light.
Hard light vs soft light
- Hard lighting creates shadows and brings out texture
- Soft lighting minimizes shadows and details.
For most interview setups, soft lighting produces more pleasing
results than hard lighting.
Spotlights generally produce harder, or more focused light than floodlights. There are three basic types: Fresnel, Ellipsoidal, & Open faced.
Fresnel - usually ranked by wattage of lamp. Fresnel
spotlights use fresnel lenses- these glass lenses have an easily indentifiable
series of coencentric rings cut into them to focus the light.
Ellipsoidal - much more directional/focusable than
typical fresnel spotlights. Examples include:
- Pattern projectors
- Follow spots
Open faced - In open faced lighting instruments, the
lamp is housed in front of a reflector, but there is no lens to focus
the light. The Lowell Omni and Tota lights are good examples of open
faced spotlights. Lighting people directly with
open faced lamps usually looks terrible. The best way to deal
with open faced lights is to use an umbrella or a diffuser of some sort.
Floodlights generally produce softer light than spotlights.
- Softlights/softboxes: my favorite key light! Chimera, Riffa lights.
Many softboxes mount over a spotlight (turning it into a soft
- Broad light: Shadows are more
defined due to the more focused output. (Not an ideal light source for lighting interviews.)
- Fluorescent & LED light bank: Provide similar light to a softbox, but with LEs or flourescent. Physically, they are shallow (only 6 inches deep or so) so
can be placed in tight locations.
Types of lamps (what actually lights up):
- Incandescent: These bulbs are larger than quartz
bulbs. These are like the typical screw-in bulbs we use at home.
They become redder with age.
- Quartz or Tungsten Halogen: encased
in a quartz bulb with halogen gas. Smaller & retains its color
temp. Don’t ever touch
with bare fingers! It will put oil on the surface and reduce the
- Fluorescent: can be almost any color temp (kinda
sorta). Consumer bulbs have uneven color values and often can appear a little green. They can work well when mixed with other light.Professional bulbs (Kino-Flo) work very well.
- HMIs: Hydrargyrum Medium Arc. It's too hard to say
so people call them HMIs. HMIs are much more expensive than typical spotlights
and are used for outdoor lighting. Sometimes called sun
they have the same
the sun. (around 5600 degrees Kelvin).
- LED - Light Emitting Diodes have grown inpopularity due to their variable color temperature, low power consumption, and long life.
We measure color temperature on the Kelvin scale
Indoor vs. outdoors (approximate color temps)
- 3200° Kelvin - indoor color temp
- 5600° Kelvin - outdoor color temp
The outdoor color temperature varies throughout day. If you want to shoot at "golden hour" (sunrise/sunset) remember to use the outdoor preset.
We can vary the color temperature with gels. Gels are useful to add an artistic look/dash of color and to correct.
Two "correction" gels are:
- CTO (Color Temperature Orange) This brings 5600° down to 3200°
- CTB (Color Temperature Blue) This brings 3200° up to 5600°.
So if we wanted to shoot in an office with windows but at an indoor color temp, we could place CTO on the windows. Alternatively if you were shooting outside but needed a little fill from a tungsten/halogen light- you could use a CTB on the light.
We measure intensity in lux or foot-candles.
Lux (European) vs. foot-candle aka lumen (American):
- A lux is the amount of light that falls on the surface of a square
meter using a candle as a light source burning one meter away
- A foot-candle is the amount of light that falls on the surface of
a square foot using a candle as a light source burning one foot away
The inverse square law states that for every foot you move away from a light
source, your intensity will drop off by 1/4
10.75 Lux = 1 foot-candle
Incident vs reflected light
- Incident light: the light falling on a subject or performance area
- Reflected light: the amount of light bouncing off or reflected from
Light meters give us objective & accurate means of determining
light intensity. Using a light meter. Point toward subject to measure
reflected light. Point towards light source to measure incident light.
Base light: the minimum operating light level
You can think of controlling light in three parameters:
- Quality (hard or soft)
- Intensity controls (control brightness)
- Area/Directional Control (How much area we're lighting)
It's important to be able to control one parameter without affecting
another. For instance we might want to adjust intensity without
affecting quality. Say we want to light our subject
with hard light, but just need to lower the output. We shouldn't use
a diffuser as it would change the light from hard to soft. So as you
choose a method to control or shape the light, be aware of how it affects
the other parameters.
Ways to control light:
- Placement - Don't forget that placement is directly related to intensity.
Move the light further away to reduce the intensity, closer to increase
- Dimmers - Good dimmers are expensive, but provide an easy way to
control intensity. Cheap (inexpensive) dimmers
may create audio interference. Variable transformers generally are
more expensive, but don't create as much RF noise.
- Gels - Gels come in many colors as well as neutral density (ND).
ND gels reduce the lamp's output without affecting quality.
- Scrims - These small screens fit into the lamp's filter holder. You
can use a half scrim to block off a portion of the light. Scrims reduce
light output without affecting the quality too much.
- Screens/net/mesh - These are often used behind subjects or over windows
in order to reduce the intensity.
- Barn doors. Helps control light spill. Stops back light from hitting
camera lens & causing lens flare
- Flags - Flags come in many sizes (2x2, 2x4, etc.) and can be clamped
to light stands. Flags can contain reflective or diffusion material
or can be completely opaque.
- Diffusers - Typically a fabric-like material that can be placed
onto a lamp (like a gel) or suspended in a flag or screen. Diffusion
softens and reduces the light output.
- Reflectors - Reflectors bounce light onto the subject from an existing
light source. Often used to provide a soft fill and can minimize
shadows. White, silver and gold are common colors. A
sheet of foam core works well as an inexpensive reflector. Glue tinfoil
to one side for more lighting options.
Jim's general tips for lighting interviews in the field
Scout a location in advance of your interview. Make sure it's available the time you need to shoot your interview. (Schedule it in advance)
Find a quiet and large room with few or no windows (or
windows you can block off). Make sure it's large enough that you can
set up multiple lights and move them around.
The most common noob mistake is using too small a room and placing their subjects against a wall.
For general interview setups, I suggest NOT using the subject's office (unless it's a great space and they have plenty of time).
Offices are usually too small and cluttered. In addition it can take
30-60 minutes to setup audio and lights for a simple, professional-looking
interview. It's an inconvenience to your subject and usually makes the
videographer feel rushed.
Try to place your subject at least 8 feet from
the background (E.g. wall). The more separation you have between your subject and the backdrop, the better it will look and the easier it will be to light. If your subject is sitting
right next to the background, your key light will hit the wall.
If the wall is lit, it will usually look terrible. So make sure there is as
much room as possible between the subject and the backround. If you
want to see background elements, (pictures, flags, awards, interesting
objects, etc) you'll want to be able to light them separately.
It's also nice to be able to place your camera a distance from
the subject so you can use a longer focal length, and minimize the apparent depth of field (throw
the background elements slightly out of focus).
Fine tune your composition. Remember the rule of thirds. Given the wide screen of HDTV, position your subject so their eyes are on either the top left or top right grid intersection. An object of interest or splash of light should balance the frame on the opposite side. Be sure you can see both of the subject's eyes. Is there a little reflection in the eyes? If so your light is in a good position.
Lighting Triangle review:
- Key - illuminates the basic shape of the subject
- Fill - Reduces and fills in shadows created by the key.
- Back -helps separate the subject from the background, creates
a figure-ground relationship.
- Background/Set - Lights setting/location. Sets mood and locale
Key light - For shooting most interviews, soft lighting
typically produces more pleasing results than hard lighting. I recommend
using a softbox for your key light. Don't point
an open face light at your subject - it looks terrible. A fresnel however
can give pleasing results. AN umbrella can as well but it spills light everywhere. I usually start by placing the key light a
little higher that the camera/interviewer. If your subject is wearing
glasses you may have to position the key light higher than normal to
reduce the reflection.
Fill - If you're using soft key light, a reflector works fine
for fill and is easily controllable. You can adjust the fill amount easily
by placement of the reflector and whether you use the white or silver
side. (You'll need a stand and spring clips to hold it.)
Back light - A little back light goes a long way. I
find I'm always using both gels and diffusion to make it look right.
(Try turning off your key light to focus and set your backlight.) This
is a good light to use colored gels on.
Set light - Highlighting a special something in the
background will add the finishing touch. This is also a good place to
use colored gels. Remember to throw the background out of focus a little
by using a small f-stop coupled with a telephoto lens.
Placing the keylight: Broad (downstage) vs Narrow (upstage) lighting
Consider if you want broad or narrow lighting. Most
interviews are shot portrait style- where the talent is slightly askew
from the camera, typically facing an off-camera interviewer.
lighting is when you position the key light on the camera side of
the interviewee's primary vector. Narrow (also known as short) lighting
is when you place the key light on the other side of the primary
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