269/369 Quiz #1 Study guide

The quiz will be composed of a selection of these questions. The page numbers refer to where the question is discussed in your handout.

Camera Buttons and Controls
Refer to class notes or p. 3 to 6 “Camera Buttons and Controls” from Dr. Robert G. Nulph

Iris (Aperture)

Q: What two aspects of the image are controlled by the iris or aperture settings on the camera?

A: 1)The size of the opening of the aperture and therefore how much light enters the camera.

2) The depth of field in the image

Q: What is controlled by the Shutter Speed

Q: Under what circumstances would you use a fast shutter speed?

Q: Under what circumstances would you use a slow shutter speed?

Q: What does White Balance effect

Q: The plane on which the focused image appears is
A: the focal Plane

Q: The place where the light rays CONVERGE is called
A: the focal point

Q: and the distance from the focal point to the axis of the lens is the
A: focal length

Q: What is “selective focus”
A: choosing to have only a part of your image (fore ground or back ground) in focus while the rest is “soft”

Q: What is “depth of field”
A: the depth or distance in the image in which it is in focus

Q: what two factors govern the extent of the depth of field:
A:1) the focal length of the lens 2) The working aperture

Q: What does opening the aperture (iris) do to your depth of field
A: it makes it smaller

Q: What does closing down the aperture do to your depth of field
A: increases it. A smaller aperture increases depth of field

Q: which aperture is smaller: f 8, f 11, f 16
A: f 16

Q: The angle of view of the lens affects the relation of objects in the foreground and background of the image. What is the effect with a narrow angle (telephoto) lens?
A: objects in the foreground and background appear to be closer to each other than than they really are. Distance is compressed.

Refer to Ch. 3 "Composition Beyond the Basics" in Grammar of the Shot

Q: Define "Depth of Field"

A:"The Depth of Fild is a zone around that point of critical focus that will appear to be in acceptable focus." p.71

Q: "As a general rule of themb the Depth of field will be found roughly_________in front of and ________ behind the plane of critical focus." (71)

A: "As a general rule of themb the Depth of field will be found roughly one-third in front of and two-thirds ehind the plane of critical focus." (71)

Q: What four factors affect Depth of Field

A: 1: Focal Lenght of Lens

2: The aperture set on lens

3: The format of the camera (such as SD or HD)

4: The Distance from the lens to the primary object of critical focus

Q: Which gives a larger depth of field a short (wide) lense or a long (narrow or telephoto type) lens?

A: short/wide

Q: Which lens aperture (small or large) has greatest depth of field?

A: Small

Q: According to the notes on p. 72 what situation provides the shallowest depth of field

A: Long lens, dark situation which requires the aperture to be wide open, and being in extreme closeup to subject.

Q: Colour Temperature refers to what?

A: The colour of light according to its temperature

Q: How is this measured?

A: In degree's Kelvin

Q: The lower number of degrees the more __________the colour will be.

A: The lower number of degrees the more warm/reddish the colour will be

Q: How many degrees kelvin is typically associated with sunlight

A: 5600

Q: How many degrees kelvin is typically associated with tungsen light

A: 3200

Q: how do you set the camera to respond to the colour of light in your shot?

A: Use the white balance

Q: What happens when you have two or more colour temperatures of light (for instance day light and tungsten light) in a shot?

A: One or the other is likely to look unnaturally intense (either too blue or too orange)

Q: A _______gel over tungsten lights can help balance them closer to daylight.

A: A blue gel over tungsten lights can help balance them closer to daylight.

Lighting:
Refer to sections from Grammar of the Shot or the on reserve reading “Lighting for Digital Video and Television", John Jackman
Name and explain the purpose of the 3 types of light used in a common 3 light set up.

Key, Fill and Back light (defined on p. 86 of Grammar of the Sho)

Make a diagram of this lighting set up.

(p. 87 Grammar of the Shot)

Q: Explain the differences between Hard Ligh and Soft Light

http://www.cybercollege.com/tvp027.htm

From an image such as that on p. 80 (Jackman) describe the position of the lights, what is specific about the light they cast (hard or soft shadows/highlights etc.)

How does using a soft box or diffuser affect your lighting

Each of the lights must be properly focused on the subject. In nearly every case, you want the of the beam to hit the subject. (84 Jackman)

A (center)

What is the approximate angle, if you imagine a clock with 12 at the top (ceiling) that a flattering key light should fall on a human subject. (86)

A) from about 1:30 to 2:30

How can the nose shadow help you determine lighting
A “the shadow should not fall too close to the upper lip( vertical angle) nor extend too far onto the cheek (horizontal angle). As a starting point, position the key so that the nose shadow falls into the fold that runs from one side of the nose to the corner of the mouth, without extending onto the cheek. “

What is a reflector? How do you use it? 87

What is an “off side key” where do the shadows fall with such a light. 97
(a key that doesn’t seem to come from the same frontal direction as the camera. The shadows fall “toward” the camera.
(From Single Camera Video Production: Focal Press)

-What are 3 ways you can control the intensity of a light (106)
-dim the light (vary the voltage), add filters or scrims, or move the instrument closer or farther from the subject.

Contrast range
You would use a light meter (which we haven’t talked about) to determine this but you can also use your eye and the zebra stripes (if you are using a more professional camera which has them) to help you determine what range to expose for or to add or take away light from you seen.

p. 108 “ If the amount of light reflected from the brightest portion of the frame in which detail is required reflects more than 30 to 40 times the light in the darkest area needed for detail then additional fill light is needed on the dark areas or some light needs to be taken off the lighter areas.

A bright sunny day is one of the most difficult shooting scenarios, why? “During a cloudless bright day, it is nearly impossible to balance the bright sun with any other light source to maintain contrast range.”
What is a solution? “The best method for balancing the lighting is to use the sun as the back light (but don’t shoot directly into the sun) and reflect the sunlight (using a reflector board) back toward the subject.

Q: What is the best /easiest type of natural lighting?
A: A slightly overcast day provides very even light.

Microphone types
Q: Describe a dynamic microphone:
A:”…the most common, most rugged, ….the pickup coil converts sound-wave energy into electric energy without an outside power source or amplification. These mikes can be designed to be relatively small and in any pickup pattern.” The dynamic microphone at SFU= Shure SM58

Q:Describe a condenser microphone
A: “is gradually replacing most other mikes…powered by small batteries or by current supplied from the amplifier (phantom power) the condenser mike has become much more practical…it is very sensitive, has a fine frequency response, and is small and lightweight. The condenser mike can be designed in any pickup patter and is manufactured in a variety of forms and price ranges.”
Condenser mikes at SFU: audio technical shotgun, lavaliere mic,

Microphone pick up patterns:

Q: What is the pick up pattern of a shotgun
Q: Cartiod
Q: Omnidirectional mic

Q: What kind of microphone would you use to mic a actor talking in a medium shot out in the street, and why?

AUDIO RECORDING:

Q: What is the range in recording (and playback) where you want to see your levels ?

A: Between -12 and -6 DB

From: Video Cameras and Lenses in the Digital Era, Robert M. Goodman (97)
Q: What is the NTSC frame rate :
A:29.97 fps (frames per second)

Q:What is the PAL frame rate (Europe, Russia, S. America etc.)
A: 25 fps

Q: What is the “normal” video aspect ratio for High Definition Video

(P 8 of grammar of the shot)

A:1.78 to 1 or 16 : 9 explain this with a diagram.

Q: If you have a screen 27 inches high how wide should it be if you were shooting in HD 16:9 mode.

Q: Explain the difference between Interlaced and progressive scan in video
A: Progressive scan
Progressive or non-interlaced scanning is any method for displaying, storing or transmitting moving images in which the lines of each frame are drawn in sequence. This is in contrast to the interlacing used in traditional television systems.

Advantages of progressive scan include:
-Subjectively increased vertical resolution. The perceived vertical resolution of an interlaced image is usually equivalent to multiplying the active lines by about 0.6. This explains, for example, why HDTV standards such as 1080i (1920x1080, interlaced) in most cases deliver a poorer subjective quality than 720p (1280x720, progressive).
-No flickering of narrow horizontal patterns
-Simpler video processing equipment
-Easier compression
see: http://en.wikipedia.org/wiki/Progressive_scan

Interlacing is a method of displaying images on a raster-scanned display device, such as a cathode ray tube (CRT), in which the display alternates between drawing the even-numbered lines and the odd-numbered lines of each frame. The word also refers to any method of storing or transmitting video in which the odd and even fields are separated.
See: http://en.wikipedia.org/wiki/Interlace

Q: How many fields in a frame of interlaced video?
A: Two. An NTSC video image consists of 525 horizontal lines of information. The electron gun scans top to bottom, left to right, odd numbered lines first, then the even numbered lines. Each full scan of even numbered lines, or odd numbered lines constitutes a "field". Each field scan takes 1/60th of a second, therefore a whole frame is scanned each 1/30th of a second. (literally 29.97 frames per second)

Q: Be prepared to identify these connectors and say what they are used for (audio/video/computer):

• RCA
• BNC
• USB
• Firewire (400, 800)
• VGA
• DVI/HDMI
• component/ composite
• XLR
• 1/4” phono
• mini stereo
• what is a hot shoe

About Lenses
From: “All About Lenses”, Jim Stinson, in Digital Videomaker, 3rd Ed. Focal Press
Q: What is Diffraction

Q: Fill in the blanks (underlined)
“When a convex lens refracts light, the light’s rays converge at a certain distance behind the lens, forming a coherent image on a plane still farther back.”

CODECS p. 214 to 2220 in he Focal Guide to Final Cut Pro and Feb 3rd on our class website.

The word codec refers to the action of "code/decode" or "compressor/decompressor" . A codec can also be thought of as a mode of compression for digital information.

"Compression" is another way to describe what a codec does.

http://en.wikipedia.org/wiki/Video_compression

Codecs are used to make data (such as video content) smaller or readable or more easily read (decoded) by other devices. There are codecs for recording (we are using pro res 422 as this is the standard of our VIXIA cameras) and for playback (in many cases we are using the H264 codec for playback as it makes a relatively small file which is easily played by quicktime.)

There are "lossy" codecs (most of the popular effective codecs fall into this category) which reduce quality to achieve compression but they attempt to maintain the impression of all the visual data being there. Jpeg is a popular "lossy" codec for images, or MPEG 2 is a compression for Standard Definition DVDs, which is also lossy.

"Lossless" codecs don't cause any loss in the data, however these are more often audio codecs.

-what is a codec

-shooting/editing and output codecs

-Shooting in Different formats

Q: What formats can you shoot with with the Vixia cameras?

A: 1080i, 720p

Q: What framerates can you shoot with with the Vixia?

A: 30, 24 fps

Q: What is the effect of shooting with 24 fps?

FRAMING TERMS, Define or explain:

2 shot

POV

180 degree rule, 102

30 degree rule, 106

master shot

shot list

Other terms:

Diagetic and non diagetic

Acousmatic