Lighting

Related notes: Light, Unreal Light

https://hg2dc.com/2022/11/07/question-29/

CIR / color temperature /

If illuminated point is 5x times away from light source is ok to use point light

at nooon bright site is x4 in afternoon is x3 at evening x2 stops

One of the most important and influential elements. Give viewer idea about shape geo depth and texture

Properties of Light Source

Primary	Direct
Secondary	Indirect

Intensity

How strong source is. TO define shape we need blackness.

• how bright / dim - how much visibility we have
• consistency -

Distance

• Close moze miec mniejsza intensity i ma fall of większy (szybciej i wyraźniej zanikanie widać z odległością) (Soft shadows, Less contrast, less edge definition ) rembrandt more
• Far zwiększyć intensywność ale wtedy falloff nie widać bo jest na wiekszych odleglosciach cień jest mniejszy i im dalej od światła tym ostrzejsze cienie żeby oświetlić. rembrandt raczej blisko gradienty (Hard shadow, deep contrast, sharper edge) less intimate more tension. Background brighter.

Scale

Wielkość światła nie zmienia falloff tylko ostrość cieni.

• Big światła da większe gradienty cienia ale nie ma gradientu jasności

SOFTNESS ! of shadow -

Direction

front / top / back .
have an impact on shadow.

Shape

Color

White balance
light temperature

for natural light sources (light RGB primes. Additive )

can transform environment

Color

Movement

to indicate life

Polarization

Not polarized

• Sun Light, bulbs, Candles are unpolarized.

Polarized

• Studio setup with filters

Partially

• Reflection (water,.. ) therefore can be partially clamped by filter
• Sky - can be used to darken the sky in photographs, increasing the contrast. (due to sunlight scattered by aerosols)
• Punkt neutralny nieba - są 4 punkty. wszystkie leżą na linii (pod nad słońcem, i 3 po przeciwnej stronie na wysokości słońca, 4 punkt pod horyzontem(punkt antysłoneczny (tylko na dużej wysokości jak słońce jest nisko))) wzorzec polaryzacyjny nawet jak słońce za chmurami.
• crystal - frozen ice crystals, which are seen here beginning to form as the water freezes. Under polarized light the ice appears to have many colors within it. The colors are due to the ice crystals being birefringent in polarized light.
• tensions on translucent materials

Cross Polarization

polarize before it reflect on surface and second time after to secure color without any reflections
1 EV cost of filter

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Properties of Material

Specular Highlights and reflection important,
Translucent
Refraction

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Shadows -

• Umbra - shadow
• Penumbra - semishadow Shadow add 3d and show shape

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Light Setup Phraseology

Key light		direct
Rim light	light around the edges of a subject	back edges
Diffuse light	that is scattered	softer
Fill light	used to reduce the contrast	diffused
Ambient	Indirect	diffused
Bounced	Indirect moon ( fog and snow, lot of bounce)

• High-key (light), - try with hdri . important to choose
• Low-key (dark) - more dramatic
• Unmotivated Light - Support light that doesn’t have a physical representation.

• one eye must be stronger

• low light ratio - low contrast between the lightest and darkest pixel
• high light ratio - contrast
• short lighting - face iluminated from side whitch is back to wiev (opposite from camera )
• broad light - frome side close to us.
• paramount light from top (with butterfly sshadow), + make chick bonsess
• loop light more from side

• checkerboard light - bright on dark and dark on bright elements

• UPSTAGE LIGHTING - key light behind eye line (in oposition to camera in dialogue witch should stay in the same site of the eye line )

• chiaro/scuro - bright/dark - renecance - davinchi and karavagiion

• lamps, stringlights candles, headlights … props

Natural Light Setup

Daylight

• Daytime (above 6°) - 8 am - 3-4 pm most difficult short shadows high contrast. harsh lighting that produces high contrast between light and shadow.
• Golden hour (from 6° to -4°) - because lighting is soft, diffused, and warm. doesn’t produce strong shadows and harsh lighting, it’s ideal for landscape photography.
• Twilights (from 0° to -18°) - Twilights are the time intervals happening between night and day, before sunrise and after sunset. The sun is below the horizon, but its light is visible because it illuminates the upper layers of the atmosphere.
  • Civil twilight (from 0° to -6°) - still enough natural light to see and distinguish objects perfectly. Sky is very bright, with colorful clouds. It’s just after sunset, the colors of the sky change most rapidly. (0-30 min After sunset) at the end of the civil twilight, drivers begin to turn on the headlights, and street lights start illuminating our cities. The horizon is clearly defined and some stars like Sirius or bright planets like Venus start to be visible. ideal for portrait and landscape photography.
  • Blue hour (from -4° to -6°) -because lighting is soft, diffused, and warm. sky has a deep blue hue
  • Nautical Twilight (from -6° to -12°) - ideal for urban and city photography. Taking advantage of the artificial lights
  • Astronomical Twilight (from -12° to -18°)

• Nighttime (below -18°) - in cinematography we are threatening night as is a day so background still lighter than foreground , (in reality farther darker cause is dark)

• Moon: , look for days when the full moon rises or sets when the sun is at an elevation between 0.5° and -6°. . If the sun is above 0.5°, the moon will be less visible

Atmosphere

Azimuth - Horizontal angle of the sun’s position.
Zenith - Vertical angle of the sun’s altitude.

Lowering contrast and saturation over distance, make color more like sky
Skylight intensity is relative to the HDR
Light - Radius and intensity keep both together. Mini roughness light without reflections

Direct lighted vs shaded intensity ratio
~4:1	sun/sky
~3:1	sunrise/sunset
~2:1	overcast

You can measure that by looking at a white surface with sun on it, and adding a shadow casting object then comparing the brightness of the lit to the shadowed areas. Modify the skylight until it’s around 25% the value of the sun. Convert to linear space if comparing in screens photoshop. (adjustment->levels and set the midpoint to 0.4545).

Shafts

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Studio Light Setup

Light types

• Flesh in camera: electric discharge lamp . tube of gas high voltage short time . high CRI and: ~5500K. lik daylight..
• IES. profiles

Softboxes - have diffusers.
Strip light - softbosx to light characters from side or behind to get rimlight. Beauty dish - bounced 2x . larger area of light but keep dir.
Umbrelas. White shoot throu, not as good cause not stoping light in other dir. Silver - keep directionality, hard contrast Gold to make warm, in portraits

Area & directionality

Light scenarios

• key light
• bounce light (with reflectors)
• rim light
• backlight - to show silhouette
• negative fill - dark and shadow

Light	Where	How	Effect
Flat	Sit-coms, passport, news	Lack of personality. One straight
Butterfly		front top. Highlight chic bones Small shadow under nose	Women
Frankenstein	Horrors	from bottom - unnatural (or to much butterfly from top )	Not natural
Split	Caravaggio	upper Side: One side black, other in light	Dramatic
Rembrandt	Side but: nose shadow touch chick and eye make light triangle.(eyes more to the light than carrav)
Loop		Side but: nose shadow almost touch chicks shadow.
Back side		Subject z boku światło z boku z tyłu
Broad side		looks more 3d z przedniej storny jak patrzysz na bok
Checkerboard		on face from right background left
Background

Campfire effect - revels underchin, make face fat

Three-point lighting It consists of a bright main light coming from one side, dim fill light coming from the opposite side, and a back light behind the subject, which is used to pick out edges and highlight form. larger, softer lights the technique of three-point lighting was abandoned,

Americen tv look

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Stage Light Setup

DMX

• Multiplexing Data Transmission
  • 1 dmx - 512 channels (dmx universe)
  • 1 controller can control multiple universes
• Dip Switch or Digital Readout - to set address of light

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Virtual Light Setup

Unreal Lighting
Sky is black and the sun is white

Scenarios

scenarios:

• like cyberpunk, lots of small colors
• visible (practical) and invisible (for fill)
• hard direct / rozproszony. Silhouettes instead of shadow
• help to emphasise silhouettes, movements and focus
• usually warm colors near and cold away
• more light u have less color saturation
• High key - superbright