Giao Trinh as Media

8/10/2019 Giao Trinh as Media

1/29

Chng 2: nh sng.

Cng nhChng 1, Chng 2 ca Media College ni vphn kthut nh sng.

Nhng v l Media nn bi vit thin vnh sng kthut ca thu hnh (video), khngphi Stage lighting. Tuy vy, vphn cbn, 2 loi hnh cng ging nhau, ng tham kho. (tuyenphuc).

Phn 1: Thut ngnh sng. LightingTerminology.

Common Lighting Terminology

Ambient Light

The light already present in a scene, before any additional lighting is added.

Ambient lightmeans the light that is already present in a scene, before any additionallightingis added. It usually refers to natural light, either outdoors or coming throughwindows etc. It can also mean artificial lights such as normal room lights.

Ambient light can be the photographer's friend and/or enemy. Clearly ambient light isimportant in photography and video work, as most shots rely largely or wholly onambient lighting.

Unfortunately ambient light can be a real nuisance if it conflicts with what thephotographer wants to achieve. For example, ambient light may be the wrong color

temperature, intensity or direction for the desired effect. In this case the photographermay choose to block out the ambient light completely and replace it with artificial light.Of course this isn't always practical and sometime compromises must be made.

On the other hand, many of history's greatest photographs and film shots have relied oninteresting ambient light. Unusual lighting can turn an otherwise ordinary shot intosomething very powerful.

Incident Light
http://www.mediacollege.com/lighting/http://www.mediacollege.com/lighting/colour/colour-temperature.htmlhttp://www.mediacollege.com/lighting/colour/colour-temperature.htmlhttp://www.mediacollege.com/lighting/colour/colour-temperature.htmlhttp://www.mediacollege.com/lighting/colour/colour-temperature.htmlhttp://www.mediacollege.com/lighting/


2/29

Light seen directly from a light source (lamp, sun, etc).

Reflected Light

Light seen after having bounced off a surface.

Colour Temperature

A standard of measuring the characteristics of light, measured in kelvins.

Colour Temperature Chart

Colour temperatureis a standard method of describing colours for use in a range ofsituations and with different equipment. Colour temperatures are normally expressed inunits called kelvins(K). Note that the term degrees kelvinis often used but is nottechnically correct (see below).

Technically speaking...

Colour temperature means the temperature of an ideal black body radiator at which thecolour of the light source and the black body are identical. (A black body is a theoreticalradiator and absorber of energy at all electromagnetic wavelengths.)

Colour Temperature in Video

For video operations the relevant temperatures range from around 2,000K to 8,000K these are common lighting conditions. In practical terms this usually means selectinglights, gels and filters which are most appropriate to the prevailing light or to create aparticular colour effect. For example, a camera operator will select a "5600K filter" touse outside in the middle of a sunny day.


3/29

Terminology

When referring to the unit kelvin, it is not capitalised unless it is the first word of asentence. The plural is kelvins (e.g. "The light source is approximately 3200kelvins").

The symbol is a capital K (e.g. "The light source is approximately 3200K"). When referring to the Kelvin scale, it is capitalised (e.g. "The Kelvin scale is

named after William Thomson (1824 1907), also known as Lord Kelvin".

Degrees kelvin

According to the The International System of Units (SI) , colour temperatures arestated in kelvins, not in degrees Kelvin. The "degrees" part of the name was madeobsolete in 1967. However, the "degrees" reference has remained in common use inmedia industries.

Contrast RatioThe difference in brightness between the brightest white and the darkest black within

an image.

Contrast Ratiois a measurement of the difference in brightness between the whitestwhite and the darkest black within an image. A ratio of 300:1 means the brightest pointin the image is 300 times as bright as the darkest point. A higher contrast ratio thereforemeans a larger difference in brightness.

Contrast ratio is of interest in two situations:

1. Cameras: When recording an image (video, film, photography)

In video and film work it is important to understand what sort of contrast ratioyour camera is able to reproduce. A high contrast ratio means that brighter anddarker areas of the image will be recorded with more accuracy and apparentdetail.

Most people don't need to know the actualspecifications but video makers need to be awarethat video has a relatively low contrast ratio. If animage includes extreme light and dark, the

camera will struggle to reproduce both. Brightareas will appear over-exposed and dark areaswill appear "crushed" (all black, lacking detail).

The example on the right illustrates a commonproblem for sports coverage in stadiums the difference between the sunlitareas and the shadows is significant.
http://www.bipm.fr/http://www.bipm.fr/http://www.mediacollege.com/lighting/contrast-ratio/camera.htmlhttp://www.mediacollege.com/lighting/contrast-ratio/camera.htmlhttp://www.bipm.fr/http://www.bipm.fr/


4/29

The best way to minimize problems with contrast ratio is to avoid having verybright and very dark objects in frame at the same time. When dealing with humansubjects it makes sense to avoid white and black clothing. Also, be wary of capsand sunglasses in strong light they can create terrible over-contrast on theface.

If you can't alter the framing, either add lighting to the dark areas or filter thebright areas.

When all else fails, the standard approach is to expose for the subject. If someparts of the picture are too bright or too dark it's not the end of the world people are used to seeing this.

Note:Film cameras generally perform better than video, but still do not reproducethe same range that the human eye would see.

2. TVs, Monitors, etc. When choosing or setting up a playback device (TV,computer monitor, etc)

Contrast Ratiois a specification given with most good televisions and monitors. Itrefers to the device's ability to reproduce different levels of brightness.

A higher contrast ratio is more desirable 500:1 is quite good.

Unfortunately the contrast ratio specification given by TV manufacturers hasbecome somewhat abused. There is a limit beyond which this specification losessignificance, as further improvements aren't noticeable in the real world. Do not

be too concerned with figures higher than 2000:1, and figures over 10,000:1 don'thave much relevance at all.

Note:Monitors also vary in their ability to display levels of gray, i.e. theirgrayscale performance. This can also effect the detail in darker areas of theimage.

Key Light

The main light on the subject, providing most of the illumination and contrast.

Fill Light

A light placed to the side of the subject to fill out shadows and balance the key light.

Back Light

A light placed at the rear of a subject to light from behind.
http://www.mediacollege.com/lighting/contrast-ratio/tv.htmlhttp://www.mediacollege.com/lighting/contrast-ratio/tv.html


5/29

Light directly from a source such as the sun, traveling undisturbed onto the subjectbeing lit.

The Standard 3-Point Light ing Technique

The Three Point Lighting Techniqueis a standard method used in visual media such asvideo, film, still photography and computer-generated imagery. It is a simple butversatile system which forms the basis of most lighting. Once you understand threepoint lighting you are well on the way to understanding all lighting.

The technique uses three lights called the key light, fill lightand back light. Naturallyyou will need three lights to utilise the technique fully, but the principles are stillimportant even if you only use one or two lights. As a rule:

If you only have one light, it becomes the key. If you have 2 lights, one is the key and the other is either the fill or the backlight.

Key Light

This is the main light. It is usually the strongest and hasthe most influence on the look of the scene. It is placedto one side of the camera/subject so that this side is welllit and the other side has some shadow.

Fill Light

This is the secondary light and is placed on the oppositeside of the key light. It is used to fill the shadows createdby the key. The fill will usually be softer and less brightthan the key. To acheive this, you could move the lightfurther away or use some spun. You might also want toset the fill light to more of a flood than the key.


6/29

Back Light

The back light is placed behind the subject and lights itfrom the rear. Rather than providing direct lighting (likethe key and fill), its purpose is to provide definition and

subtle highlights around the subject's outlines. This helpsseparate the subject from the background and provide athree-dimensional look.

If you have a fourth light, you could use it to light the background of the entire scene.

Soft Light

Light which appears to "wrap around" the subject to some degree. Produces lessshadows or softer shadows.

Spot A controlled, narrowly-focused beam of light.

Flood

A broad beam of light, less directional and intense than a spot.

Tungsten

Light from an ordinary light bulb containing a thin coiled tungsten wire that becomesincandescent (emits light) when an electric current is passed along it. Tungsten colour

temperature is around 2800K to 3400K. Also known as incandescent light.Halogen

Type of lamp in which a tungsten filament is sealed in a clear capsule filled with ahalogen gas.

Fresnel

A light which has a lens with raised circular ridges on its outer surface. The fresnel lensis used to focus the light beam. Incandescent Incandescent lamps produce heat byheating a wire filament until it glows. The glow is caused by the filament's resistance tothe current and is called incandescence.

Measuring Light Unit.

There are many different units for measuring light and it can get very complicated. Hereare a few common measurement terms:


7/29

Candela (cd)Unit of luminous intensity of a light source in a specific direction. Also called candle.Technically, the radiation intensity in a perpendicular direction of a surface of 1/600000square metre of a black body at the temperature of solidification platinum under apressure of 101,325 newtons per square metre.

Footcandle (fc or f tc)Unit of light intensity, measured in lumens per square foot. The brightness of one candleat a distance of one foot. Approximately 10.7639 lux.

Lumen (lm)Unit of light flow or luminous flux. The output of artificial lights can be measured inlumens.

Lux (lx)Unit of illumination equal to one lumen per square metre. The metric equivalent of foot-

candles (one lux equals 0.0929 footcandles). Also called metre-candle.

These are some common types of light you'll often hear about in film, video andphotography. Note that these definitions are not always rigid and some people mayinterpret them a little differently.

1000-2000w, used as a key flood light for large areas.

A blondelight is basically a bigger version of a redhead. Power ratingcan be 1000 to 2000 watts, although the term generally refers to a

Blonde
http://www.mediacollege.com/lighting/types/redhead.htmlhttp://www.mediacollege.com/lighting/types/blonde.htmlhttp://www.mediacollege.com/lighting/types/blonde.htmlhttp://www.mediacollege.com/lighting/types/redhead.htmlhttp://www.mediacollege.com/lighting/types/blonde.html


8/29

2000w open-face unit.

These are powerful lights, useful as key floodlights for lighting largeareas.

The example pictured here is an Ianiro 2Kw blonde.

Note:The term "blonde" is often used loosely there is no rigiddefinition.

Redhead 650-1000w, used as a key flood light for large areas.

Red Head is a term used to describe general-purpose lights commonin visual media work. Power rating is around 650-1000w, typically800w.

Red heads can be used as a key flood light for large areas, but arealso useful as fill and backlights.

The example pictured here is an Arrilite 800w open-face focusingtungsten floodlight. The beam is focused using the yellow control atthe back this adjusts the reflector rather than the lamp, whichshould give the lamp a longer life because it is not being moved.

Note:The term "redhead" is often used loosely there is no rigiddefinition.

Pepper Light 100-1000w, small light used as a more focused key or fill light.
http://www.mediacollege.com/lighting/types/redhead.htmlhttp://www.mediacollege.com/lighting/types/redhead.htmlhttp://www.mediacollege.com/lighting/types/pepper.htmlhttp://www.mediacollege.com/lighting/types/pepper.htmlhttp://www.mediacollege.com/lighting/types/redhead.html


9/29

Pepper lights are small lights, around 100 - 1000w (200w is common).They can be used as key or fill lights in small areas, or to light acertain feature, create lighting contrast and effects, etc.

Pepper lights can be also be used to accent a person's eyes.

HMI A high-quality type of light which uses an arc lamp instead of filamentbulb.

HMI (Hydrargyrum Medium-Arc Iodide)is a type of light which uses anarc lamp instead of an incandescent bulb to produce light.

HMI lights are high-quality and correspondingly expensive. They arepopular with film and television production companies but their priceputs them out of reach of those with modest budgets.

HMI lights require a ballast, an electronic (or magnetic) device whichprovides the ignition pulse and regulates the arc.

Advantages of HMI lights include:

Efficiency: 2 to 5 times as efficient as incandescents. Thismeans they use less power and run cooler.

Colour temperature: HMIs run at around 5600K, daylight
http://www.mediacollege.com/lighting/types/hmi.htmlhttp://www.mediacollege.com/lighting/types/hmi.html


10/29

temperature. This makes daylight shooting easier, as well aseliminating loss of light from gels (which are necessary withincandescents).

Light Quality: Directors of photography speak highly of the lightproduced by HMIs.

Halogen WorkLamp

150-500w, used as a key flood light for lighting large areas. This is alow-budget lighting solution.

Halogen work lampsare designed for workplaces and similarsituations where a flexible means of providing strong lighting isrequired, e.g. builders, mechanics, etc. Work lamps come in varioussizes and configurations, from portable units with handles to stand-mounted multi-head versions. Power rating is generally 150w to 500w.

Halogen work lamps are sold by trade suppliers and DIY stores.

Work lamps can be a cheap option for video lighting. They are usefulas a key flood light for lighting fairly large areas.

You must remember though, that these lamps are not specifically

designed for video or photography. They are not ideal and usuallyrequire a diffusion gel for the best effect. The protective grills may alsointerfere with the light (you may be able to remove them).

You might also want to consider waterproof work lamps for extrasafety, especially if you are working outdoors.
http://www.mediacollege.com/lighting/types/halogen-work-lamp.htmlhttp://www.mediacollege.com/lighting/types/halogen-work-lamp.htmlhttp://www.mediacollege.com/lighting/types/halogen-work-lamp.htmlhttp://www.mediacollege.com/lighting/types/halogen-work-lamp.html


11/29

Other Lights Domestic light bulbs can be used at a pinch, ideally as a secondarylight such as fill or backlight.Many video cameras have built-in lights or the ability to mount a light

these are useful in emergencies but provide poor quality lighting.

ChineseLanterns

A low-cost light, useful in some situations.

chinese lanternis a paper ball (or cylinder, cube, etc) with a light bulbin the middle. They are very cheap to buy and use a standardhousehold light bulb.

For video and photographic work, chinese lanterns are obviouslylimited by the small amount of wattage. However they do create a nicelight that can be useful for close-up shots. In a wider setting, multiplelanterns can be used for effect.

Being made of paper, chinese lanterns are potentially dangerous.

They can catch fire so be careful. For storage they can be collapsed toa disk the same diameter as the expanded sphere.

Instruments / Housing

Fresnel A light which has a lens with raised circular ridges on its outer surfacewhich are used to focus the light beam.
http://www.mediacollege.com/lighting/types/chinese-lantern.htmlhttp://www.mediacollege.com/lighting/types/chinese-lantern.htmlhttp://www.mediacollege.com/lighting/types/chinese-lantern.htmlhttp://www.mediacollege.com/lighting/types/fresnel.htmlhttp://www.mediacollege.com/lighting/types/fresnel.htmlhttp://www.mediacollege.com/lighting/types/chinese-lantern.htmlhttp://www.mediacollege.com/lighting/types/chinese-lantern.html


12/29

chinese lanternis a paper ball (or cylinder, cube, etc) with a light bulbin the middle. They are very cheap to buy and use a standardhousehold light bulb.

For video and photographic work, chinese lanterns are obviously

limited by the small amount of wattage. However they do create a nicelight that can be useful for close-up shots. In a wider setting, multiplelanterns can be used for effect.

Being made of paper, chinese lanterns are potentially dangerous.They can catch fire so be careful. For storage they can be collapsed toa disk the same diameter as the expanded sphere.

Phn 2: Thit bnh sng. Lighting Equipment

Some common types of equipment used in video and photography lighting.

A gray-coloured card which reflects 18% of the light which falls upon it.Used as a reference to calibrate light meters and set exposure.

An 18 Percent Gray Cardis a simple gray-coloured card whichuniformly reflects 18% of the light which falls upon it. Gray cards canbe used as a reference to set the camera exposure or to calibrate alight meter (light meters are used to determine which exposure settingis required to produce a medium gray tone).

Gray cards are usually made from coated cardboard or polystyreneand come with a protective cover. They are an inexpensive and usefuladdition to the photographers' kit.

How to Use a Gray Card

To set your exposure with a gray card, first make sure the camera is inmanual mode or is able to hold its settings when you half-depress theshutter button.

Position the card immediately in front of the subject, ensuring that thelighting on the card is exactly the same as the lighting on the subject.If you are using a light meter, take your reading now. Otherwise, half-

18% GrayCard
http://www.mediacollege.com/lighting/equipment/gray-card.htmlhttp://www.mediacollege.com/lighting/equipment/gray-card.htmlhttp://www.mediacollege.com/lighting/equipment/gray-card.htmlhttp://www.mediacollege.com/lighting/equipment/gray-card.htmlhttp://www.mediacollege.com/lighting/equipment/gray-card.html


13/29

depress the camera shutter button to save the exposure setting untilyou fully depress the button (and take the picture).

(Note: This process is very similar to performing a white balance).

Tips At the start of your roll of film, take one photo of a gray card.

This acts as a colour correction reference for the film processor. Do not use any old gray piece of cardboard for a gray card. You

really need a professionally-made one. When you first purchase a gray card, run a series of tests to

establish exactly how it performs in both bright outside light andlower artificial light. Use slide film rather than print, as slide filmdoes not correct exposure errors.

Ballast A device used to control the electrical current in a light.A ballastis an electrical device used to control the current in anelectrical circuit. A lighting ballast controls the start-up and regulationof fluorescent and high intensity discharge (HID) lamps.

A ballast is necessary for fluorescent and HID lamps because theyhave a negative resistance, which means if they are connected to aconstant voltage source they will continue to draw more current untilsomething melts down. The ballast controls the current and keepseverything working correctly.

Ballasts come in many varieties and complexities, from a simpleresisters to computer-controlled units.

Consoles Hardware and software systems which control lighting. Operated bythe lighting technician, consoles coordinate lighting displays onstages, studios, etc.

Lighting consolesare systems which control lighting - much as asound mixercontrols audio and a vision switcher controls video.

Consoles are typically a combination of hardware and software.

Operated by a lighting technician, consoles are used in a wide rangeof applications including stage, studio, film set, etc.

Modern consoles include options for automating certain tasks andeffects. Complex productions rely heavily on such automation.
http://www.mediacollege.com/video/camera/white-balance/http://www.mediacollege.com/lighting/equipment/ballast.htmlhttp://www.mediacollege.com/lighting/equipment/ballast.htmlhttp://www.mediacollege.com/lighting/equipment/console.htmlhttp://www.mediacollege.com/audio/mixer/http://www.mediacollege.com/lighting/technician/http://www.mediacollege.com/lighting/technician/http://www.mediacollege.com/audio/mixer/http://www.mediacollege.com/lighting/equipment/console.htmlhttp://www.mediacollege.com/lighting/equipment/ballast.htmlhttp://www.mediacollege.com/video/camera/white-balance/


14/29

LightMeter

A tool used to measure light and indicate the ideal exposure setting.Also known as an exposure meter.

A light meter, also known as an exposure meter, is a tool used tomeasure light levels. Light meters are commonly used in photography,motion film and video to help determine the ideal exposure setting.

Many cameras have built-in light meters and this function is oftencarried out automatically. However serious professionals still regularlytake manual readings.

ReflectorBoard

A specially-designed reflective surface used to act as a secondarylight source. The board is lightweight and flexible, and is normally

folded up for transport in a small carry-case.

Sometimes referred to as a "flecky board", this is a specially-designedreflective surface which is usually used to act as a secondary lightsource. It is particularly useful as a fill light when working in strongsunlight.

Reflector boards come in white, silver or gold surfaces. Manyreflectors have a different type of surface on each side, giving you twolighting options. Gold surfaces provide a warmer look than silver orwhite.

If you don't have a reflector board you can improvise. Almost anysuitably-sized object with a reflective surface will do. Some examplesinclude:

Windscreen sunshades for automobiles Polystyrene sheets Tin foil on cardboard (try both sides of the foil for different

effects) Whiteboard

How to Fold Up a Reflector Board

Reflector boards are lightweight and flexible, and are normally foldedup for transport in a small carry-case. They can be tricky to fold up if you've never done it you may want to read the instructions belowand practice in private before having to do it in front of the whole crew!
http://www.mediacollege.com/lighting/light-meter/http://www.mediacollege.com/lighting/light-meter/http://www.mediacollege.com/lighting/equipment/reflector-board.htmlhttp://www.mediacollege.com/lighting/equipment/reflector-board.htmlhttp://www.mediacollege.com/lighting/equipment/reflector-board.htmlhttp://www.mediacollege.com/lighting/equipment/reflector-board.htmlhttp://www.mediacollege.com/lighting/equipment/reflector-board.htmlhttp://www.mediacollege.com/lighting/light-meter/http://www.mediacollege.com/lighting/light-meter/


15/29

Hold the board with your left hand facing

forward and your right facing backward.

Move your left hand forward and down,

while moving your right hand backwards

and up.

Keep moving your hands in a

smooth motion.

The board will end up folded in a

compact circle. You can then return

the board to its case.

Hold

the

board

with

your

left

hand

facing

forward

and

your

right

facing

backward.

Moveyourlefthandforwardanddown,whilemovingyourrighthandbackwards

andup.Keepmovingyourhandsinasmoothmotion.Theboardwillendupfolded

inacompactcircle.Youcanthenreturntheboardtoitscase.

Gels Materials which are placed in front of a light source to alter it'scharacteristics, e.g. colour temperature or dispersion .

Diffusion Gels & Materials

In the context of lighting, diffusionmeans to spread the light beam outand make it more random.

When you have a single source of light like the sun, the resulting lightis very directional and will create shadows where the light does notfall. On an overcast day, water particles in the clouds diffuse thesunlight and make it appear to be coming from the whole sky(reducing shadows in the process).

Video lights tend to create directional light. In some cases this isdesirable but sometimes this type of light can be too harsh. Inparticular, you don't usually want strong shadows on a person's face.

One way to mitigate this problem is to use some sort of diffuser. Thisusually comes in the form of a gel, filter or piece of material which isplaced in front of the light. Professional light fixtures have specialholders or clips on the barn doors to attach gels and filters. Woodenclothes pegs can also be used.


16/29

More elaborate setups might use large sections of diffusion materialmounted in a frame, or in a "softbox" like those pictured left.

You can also bounce light of walls, ceilings and materials (e.g.foamcore) to create different diffusion effects.

Warning:Always be very careful when mounting any gel or materialnear a light. Lights can get very hot avoid flammable material andnever attach plastic pegs to a light fixture.

Spectrometer

A professional-level instrument which measures the spectrum of light.Technically speaking, a spectrometer analyses the electromagneticspectrum and measures the intensity of radiation as a function ofwavelength.


17/29

Systems used to support lights and hold them in the correct position.

In the context of lighting equipment, the term Lighting Supportrefers tothe range of systems used to support lights and hold them in thecorrect position. This usually means light stands and clamps. Clamps

and other accessories are sometimes referred to as grip gear.

Like microphone stands, most lighting standsand clamps use a standard system of fittin

Stands &Clamps

gs.

On simple light stands like the ones pictured, thelight slides down onto the fitting and screws tight.

Clamps like those below can be attached to anyappropriate solid object.
http://www.mediacollege.com/audio/microphones/stands.htmlhttp://www.mediacollege.com/lighting/equipment/support.htmlhttp://www.mediacollege.com/lighting/equipment/support.htmlhttp://www.mediacollege.com/audio/microphones/stands.htmlhttp://www.mediacollege.com/lighting/equipment/support.htmlhttp://www.mediacollege.com/lighting/equipment/support.html


18/29

Phn 3: Lighting For Video & Television

Video lighting is based on the same principles as lighting for any other visual media. Ifyou haven't done so already, you should read through our general lighting tutorialsbefore reading this page, which deals specifically with lighting issues for video.

Light Sources

All video uses some sort of lighting, whether it be natural light (from the sun) or artificiallights. The goal of video lighting is to choose the best source(s) to achieve your goals.

First and foremost you need enoughlight. You must ensure that your camera is able torecord an acceptable picture in the conditions. With modern cameras this is seldom aproblem except in very low light or strong contrast.

Assuming you have enough light, you must then consider the quality of the light andhow the various light sources combine to produce the image.

If you have clashing light sources (e.g. artificial interior lights with sunlight comingthrough the windows), you may find the colours in your image appear unnatural. It's bestto control the light sources yourself if possible (e.g. turn off the lights or close thecurtains).

When moving between locations, think about what light source you are using. If youmove from an outside setting to an inside one with artificial lights, the amountof light

may seem the same but the colour temperaturewill change according to the type oflights. In this case you need to white balanceyour camera for the new light source.

Contrast Ratio

Contrast ratiois the difference in brightness between the brightest and darkest parts ofthe picture. Video does not cope with extreme contrast as well as film, and nowherenear as well as the human eye. The result of over-contrast is that some parts of thepicture will be too bright or too dark to see any detail. For this reason you need toensure that there is not too much contrast in your shot. See Camera Contrast Ratioformore details.

Camera-Mounted Lights
http://www.mediacollege.com/lighting/http://www.mediacollege.com/lighting/colour/colour-temperature.htmlhttp://www.mediacollege.com/video/camera/white-balance/http://www.mediacollege.com/lighting/contrast-ratio/camera.htmlhttp://www.mediacollege.com/lighting/contrast-ratio/camera.htmlhttp://www.mediacollege.com/video/camera/white-balance/http://www.mediacollege.com/lighting/colour/colour-temperature.htmlhttp://www.mediacollege.com/lighting/


19/29

The camera-mounted light is an easy, versatile solution used by amateurs andprofessionals alike. Typically the light will draw power from thecamera battery, although aseparate power supply can be used. Be aware that lights which draw power from thecamera battery will significantly shorten the battery's charge time.

This type of lighting does not create pleasing effects. it is a "blunt instrument" approachwhich is really only designed to illuminate the scene enough to allow normal cameraoperations. However it is a simple, practical solution.

Night-Mode Video Shooting

Some cameras offer a special "night vision" option which allows you to shoot withvirtually no light. This mode uses infrared light instead of normal visible light.

This is useful in extreme circumstances when you have no other option. Unfortunatelythe results tend to be poor-quality monochrome green.

Of course, you can use this mode for a special effect if it suits the content.

Lighting Interviews

The normal rules of lighting apply to interviews. This page covers some general tipsspecific to interview lighting, whether or not you have your own lights. See our lightingtutorialsfor more detailed information about lighting technique.

If You Have Your Own Lights

You need to decide whether or not they are actuallynecessary. Although conventional wisdom says you shouldcontrol interview lighting yourself if possible, in manysituations the existing light will be fine and more practical.

Shooting outside

The weather will obviously influence your decision. If thenatural light is sufficient there may be no need to addartificial light. If you do use your own lights you will need toadd the appropriate gels to match your lights to the daytimecolour temperature. If the sun is too strong you could find ashady location.
http://www.mediacollege.com/lighting/http://www.mediacollege.com/lighting/http://www.mediacollege.com/lighting/http://www.mediacollege.com/lighting/


20/29

Shooting inside

Find the best location - ideally a room with plenty of space and the ability to controlexisting light. Unless you have a good reason to use existing light sources, try toeliminate them all (close curtains, turn off lights, etc). Then set up your own lights.

If You Have No Lighting

In many situations you are limited to the available light. Thisis where a reflector board(pictured) can be a lifesaver.Easy to carry and use, it can create useful lighting effectsand compensate for unfavourable conditions. If you don'thave a reflector board you can sometimes improvise withother reflective objects.

Shooting outside

With luck the natural sunlight will be fine, using the sun asthe key light. If the sun is low, be careful not to make theguest squint. Strong sunlight creates strong shadows whichcan be balanced with a reflector.

Shooting inside

Try to avoid mixed lighting, e.g. sunlight through a window mixed with artificial light.Depending on the strength and quality of light sources, you could either turn the artificiallights off or block out the window light.

Overhead lights aren't desirable as they create ugly shadows on the face. If they are allyou have you may be able to balance them with a reflector.

Camera-Mounted Lights

In many situations a light mounted on the camera is all you have.This is common in mobile operations such as news coverage.

Although it is a simple, practical solution, it does not produceparticularly good lighting and should only really be used whenbetter lighting is not possible.

Note:Lights which draw power from the camera battery will reduce the battery's chargetime.
http://www.mediacollege.com/lighting/equipment/reflector-board.htmlhttp://www.mediacollege.com/lighting/equipment/reflector-board.html


21/29

Editing Interviews

Before you shoot your interview you must know how it will be edited. For example, ifthere are going to be lots of other shots inserted you may want to hold a static shotthroughout the IV so that these shots can easily be added anywhere. On the other

hand, if there is to be little or no editing you may want to vary your shots to maintaininterest.

Despite the many different styles of interview, most have a fairly common basicstructure. The following example outlines a typical approach:

Establishing

ShotA very wide shot which shows the location. Not always necessary.

2-Shot A visual introduction to both interview participants (interviewer and

guest). Usually a wide shot or MCU.

1-Shot Begin concentrating on the guest with an MCU and overlay name/titlekey.

Questions &

NoddiesWhile most of the interview concentrates on the guest, the interviewer is

occasionally shown asking and responding to questions.

Cutaways When appropriate, relevant cutaways can be dropped in.

Cutting Between Interviewer and Guest

The most common edit is the cut between shots of interviewer and guest, whether it belive cuts between cameras or post-production edits.

The natural instinct is to cut exactly between the end of a question and the beginning ofthe answer. However this tends to look stilted. Try cutting a little before or after thequestion/answer is complete.

In live multi-camera situations it's easy to get caught behind the action, cutting to thewrong person at the wrong time. This can happen, for example, when you expect oneperson to speak but another person does. Do not "chase" the person speaking - it'sbetter to have a shot of someone else listening for a few seconds than to cut quickly tothe speaker and draw attention to your mistake. If you have the luxury of a wide shot,this can often get you out of trouble.


22/29

Back-Cut Questions

If you are using one camera and the IV is to be edited in post-production, the usualroutine is to concentrate your framing on the guest during the interview. Then when theinterview has finished you reposition the camera to face the interviewer and shoot them

asking the questions again. The interviewer is in exactly the same position as they wereduring the IV, facing the empty space where the guest was (which is of course out ofshot). These shots are then inserted into the interview over the original questions. Theresult is an interview which looks like it was shot with two cameras.

Obviously it's important to record the back-cut questions exactly the same as they wereasked during the actual IV. You will usually have a pre-prepared list of questions to helpyou, but you should also make notes during the IV of any new questions.

Make sure your positioning and eyelines are consistent, as well as microphoneplacement.

Noddies

"Noddy" is the term given to a shot of the interviewer reacting to the guest. Theinterviewer may be nodding, smiling, frowning, looking concerned, etc.

Noddies perform two functions.

To include the interviewer and show their reactions. To provide edit points.

Noddies are shot in the same way as the back-cut questions. The interviewer faces thesame direction and provides a series of nods, smiles and any other expressionsrelevant to the interview. This is difficult for inexperienced presenters and will causemuch hilarity for anyone watching who has never seen it done before.Note:If you are tempted to laugh and make jokes at your first professional shoot - don't!Experienced presenters have heard all the noddy jokes a million times and it just showshow new you are.

In the edit suite, whenever you need to remove a segment of the guest's speech you

simply inset a noddy to cover the edit. Obviously the noddy must be appropriate - youdon't want a shot of the interviewer smiling as the guest relates a tragic incident. This iswhy you must make sure you shoot the whole range of expressions - so you'll alwayshave the right one for the edit.

Note:For better or worse, noddies can give emotional cues to the viewer. For example,if a guest is reciting some facts and figures, a shot of the interviewer looking shockedsuggests to the audience that these figures warrant a strong reaction.


23/29

Some More Rules:

When shooting for post-production create clean lead-in and lead-out space, and include

information about the IV content.

At the beginning of the IV have the presenter record a brief intro and 3-secondcountdown, leaving the "one" silent, e.g:"IV with John Smith regarding environmental contamination, starting in 3... 2....(silence)..."The interviewer then begins the actual interview on "zero".

At the conclusion of the interview, pause and don't move. This stops the guest fromimmediately looking or walking away, providing you with enough time to mix or wipeaway to the next shot.

Keep an eye on looking room and direction. When gathering and editing lots of different

shots you must be constantly ensuring that everyone is facing the right way. Forexample, if you shoot your back-cut questions the wrong way the interviewer and guestwill appear to be facing opposite directions.

Cutaways and noddies will save your edit. You can't have too many of them.

General Tips for Shooting Interviews

The KISS PrincipleWhen you're starting out shooting IVs it's probably best to keep it simple. It's better tohave a boring static shot for 60 seconds than an empty or soft shot. Remember, theimportant stuff is what the guest is saying, not how creative your framing is.

Dealing with Newbie Guests

Guests who have never been interviewed before can be a challenge, especially if theyare very nervous. It's important to reassure them and make them feel comfortable. Hereare a few things you might find yourself saying to the nervous newbie:

"Just treat it as a normal conversation. There's no reason for you to worry aboutanything else that's happening. The best thing you can do to look good for the camerasis to ignore them."

"Don't worry if you make a mistake or muddle up your words - just carry on. It actuallyhappens all the time in interviews, but because it's something the audience is used toseeing in everyday conversations they won't even notice."


24/29

"You look fine!"

Note:If the interview is to be edited, you can point out that any serious mistakes can becut out.

Pace Yourself (and Everyone Else)

Fatigue is the enemy. Interviewers and guests who are tired do not perform well, so becareful not to exhaust them. When preparing the set, use stand-ins to take their placewhile you set up the shots. Do not ask for multiple takes unless necessary (you willoften find the first take is the best anyway).

Clothing

Beware of clothing which is un-camera-friendly. This includes shirts and jackets withfine patterns which produce the moire effect. Dark glasses or caps which obscure/shadethe eyes are not good.

Be Prepared

Think about everything that could happen during the interview. Especially if you'reshooting off-the-shoulder and there's a chance that your subjects could move around,you need to know how you're going to move. Try to ensure that unwanted bystandersaren't going to interrupt the IV.

Summary

Interview technique is a required skill for any serious camera operator. Know what the goal of the interview is and stay focused on that goal. Know the editing requirements. Double-check everything, then do it again. Be prepared for anything.

Lighting with Background Windows

Shooting pictures indoors with external windows is a common issue for photographersand video makers. The large difference in light levels between the room and the outsideview make finding the correct exposure a challenge. Video is particularly susceptible tothis problem due to it's relatively low contrast ratio.

If you can't avoid having the window in shot, in most cases the only thing you can do isuse the manual iristo set your exposure correctly for the subjects in the room. Thismeans that the window will be over-exposed but that's a necessary compromise. If you
http://www.mediacollege.com/lighting/contrast-ratio/http://www.mediacollege.com/video/camera/exposure/http://www.mediacollege.com/video/camera/exposure/http://www.mediacollege.com/lighting/contrast-ratio/


25/29

wish to show the outside view, expose the iris for the window (which will make the roomdark).

If you have time and resources available, there are two things you can do to help evenout the lighting so it's possible to capture both areas effectively:

1. Add more light to the room2. Reduce the light from the window

(1) Increase the Lighting in the Room

Any extra light you can shine on the subject will decrease the contrastratio between them and the window.

In some cases switching on the standard room lighting can help, althoughthis often introduces new problems such as clashing colour temperaturesand harsh downward shadows.

It's possible that a reflector boardcould be useful.

(2) Reduce the Light from the Window

You can reduce the amount of light comingthrough the window by placing some sort offilter over it.

In the example pictured here, black scrim (afine mesh material) is taped to the window.You can see that the background is muchmore manageable through the scrim.

If the entire window needs to be in shot you'll

need to be careful and discreet with the scrim/filter. It can be difficult getting exactly theright fit. If only part of the window is in shot it's a lot easier.

Filters can cause unwanted side effects such as ripple and the moire effect. Beingfurther away from the window helps.
http://www.mediacollege.com/lighting/colour/colour-temperature.htmlhttp://www.mediacollege.com/lighting/equipment/reflector-board.htmlhttp://www.mediacollege.com/lighting/equipment/reflector-board.htmlhttp://www.mediacollege.com/lighting/colour/colour-temperature.html


26/29

Lighting Effects

Cold / Warm

You can add to the feeling of coldness or warmth by using additional filters or doublingup on gels. Very blue means very cold, very red/orange means very hot.

Moonlight (or any night-time light)

This is an old standard technique which has become something of a clich. You canmake daytime seem like night by lowering the exposure slightly and adding a blue filterto the camera. However a convincing illusion may require more effort than this youdon't want any daytime giveaways such as birds flying through shot. You also need tothink about any other lighting which should appear in shot, such as house or streetlights.

Firelight

To light a person's face as if they were looking at a fire, try this: Point a redhead withorange gel away from the subject at a large reflector which reflects the light back at thesubject. Shake the reflector to simulate firelight (remember to add sound effects aswell).

Watching TV

To light a person's face as if they were watching TV, shine a blue light at the subjectand wave a piece of cloth or paper in front of the light to simulate flickering.

DIY Lighting Kit

Professional lighting kits for video and photography are very expensive. Fortunately forthe budget-impaired enthusiast, it is possible to put together a perfectly adequatelighting kit for less than $US100.

A good beginner's lighting kit should include:

Three (or more) lights with stands Reflector board(s) Power cables, extension leads and a multi-box.


27/29

The Lights

The standard budget light is the halogen work lampwhich can be found at anyhardware store or purchased at amazon.com for as little as $US10. These come with orwithout a stand and range from around 150W to 500W.

The stand-less units have a small handle and can be rested on any solid surface suchas a table or the floor. This is not ideal for your main lights but it can be useful for filllighting, backgrounds, etc. In any case these units are so cheap that it can't hurt to buya couple.

Lights with stands are more versatile and you should have at least one of these(preferably two or three). Try to find a stand which goes up to around 2 metres (theheight of a tall person). Taller than 2 metres would be even better but this type of lightstand doesn't normally go that high.

Some lights (like the W12665 unit pictured) can be used with or without the stand,making them even more versatile.

One drawback of these cheap lights is that the colour of the light is quite yellow. As longas you white-balance your camera this isn't a huge issue, but if you want the bestquality lighting you can try one of these solutions:

1. Purchase a 32K white bulb (ask your hardware supplier).2. Place a coloured gel in front of the light to correct the colour.

Speaking of gels, the other big drawback of these lights is that there is no built-in

system for mounting accessories like gels and diffusers. You can improvise by creatinga wire holder or separate stand for accessories.

You will also find that you can't alter the spread of these lights, i.e. from floodlight tospotlight. This is not a big concern for most people but if you do need this functionalityyou might need to consider a professional video lighting kit.

Reflectors

Professional reflector boardsare used to add or control light ina scene. You can make your own from just about any large

reflective object, although the exact colour and reflectivity willobviously affect your lighting. Common suggestions for animprovised reflector include:

Windshield sunshade (pictured) Sheet of foamcore Polystyrene sheet
http://www.mediacollege.com/lighting/types/halogen-work-lamp.htmlhttp://www.mediacollege.com/lighting/equipment/reflector-board.htmlhttp://www.mediacollege.com/lighting/equipment/reflector-board.htmlhttp://www.mediacollege.com/lighting/types/halogen-work-lamp.html


28/29

Stiff cardboard, or tin foil on cardboard (try both sides of the foil for different effects) Whiteboard Survival blanket (gold on one side and silver on the other)

Hobby shops have a lot of items which may be of interest. Online auction sites are alsoworth checking as reflectors can often be found fairly cheap there.

Power

You will need a few power extension cables of varying lengths, plus one or more multi-boxes with built-in trip switches. It helps to have a separate carry case for power cables.

Safety

Lights get very hot! Seriously, you can burn yourself badly or set fire to things. Lights can draw a lot of current so be careful not to overload power sources.

If you're working outside, use an isolating transformer on your power.

Lighting Safety Tips

Keep bystanders away from lights they are notorious for knocking them over.

Always be extremely careful with the heat created by lights. The barn doors can burnyour fingers. Wait until lights cool down before touching or moving them.

Don't handle bulbs with your fingers use a piece of cloth or something else.

Only use material for gels which is specifically designed for lighting. Don't use paper,tracing paper, baking paper, plastic, etc. Never attach anything to a light which isn'tdesigned for the application.

Make sure stands are stable and loose cables are taped to the ground.

Lights are power-hungry don't overload sockets. Never plug more than 2Kw oflighting into a domestic power point.

Make sure all lights have adequate ventilation and never cover them.

Tips for Lighting People

Harsh light is not flattering; soft light creates a warmer feel.


29/29

Avoid strong nose shadows or any strong contrast on the face. Place the key light onthe same side as the camera and fill the shadows.

Avoid reflections from glasses. You may need to adjust the position of the subjectand/or lights to do this.

Beware bald heads they can reflect a lot of light and appear over-exposed. Tryweakening or softening the light with a diffusion gel.

Soft light and diffusion helps reduce the appearance of wrinkles.

Giao Trinh as Media

Documents

Transcript of Giao Trinh as Media