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 p. 3 to 6 “Camera Buttons and Controls” from Dr. Robert G. Nulph
This will be a practical part of the exam. Be able to identify, define and use the following controls on your or the school’s cam corder:
Focus
Zoom
Iris (Aperture)
Shutter Speed
White Balance

Lighting:
Refer to sections from “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.

Make a diagram of this lighting set up. (p. 83)

From an image such as that on p. 80 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)
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 com 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 (be sure you know what these are) on a more professional camera 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:
What is the pick up pattern of a shotgun
Cartiod
Omnidirectional mic

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
A: 16:9 explain this with a diagram.

Q: If you have a screen 45 inches high how wide should it be if you were shooting in 16:9 mode.

A: 45 divided by 9 x 16

Q: How many fields in a frame?

A: Two. An NTSC SD video image consists of 525 horizontal lines of information an interlaced HD (high definition) video image consists of 1080 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: 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: The camera may offer you a choice of shooting interlaced or progressive. How is this designated?

A: You may have the choice between 1080i or 720p (or 1080/24p)

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

• RCA
• BNC
• HDMI
• DVI
• VGA
• Firewire
• XLR
• 1/4” phono
• mini stereo

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.”

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 aperature increases depth of field

Q: which aperature 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.

Data Rates: see data_rates.html

Define "data rate"

How is Data Rate measured

What is the Data Rate of USB 2

What is the Data Rate of Firewire 800

Video Colour Sampling (Chroma Sampling) see related page

CODECS

What is a video Codec: see related page

What three general types of CODECS have we discussed

-Codec for image capture

-Codec for post production, sometimes called an "Intermediate" codec.

-Codec for playback or distribution, such as H264

What distinguishes Apple Prores 422 (the codec you are using) : makes large files but they is simpler to decode, therefore take less time/processor power, than other codecs. Although it is "lossy" (it throws some information away) it preserves the image very well.

FINAL CUT PRO TOPICS WHICH MAY BE ADDRESSED:

Final Cut Pro:

- how to set your scratch discs in Final Cut.

importing media "log and transfer" "capture now" -identify and describe the functions of the browser, timeline, viewer and canvas,

-describe an insert and overlay edit

- how to export to H264 using "Quicktime Conversion"

Soundtrack Pro:

-identify the difference between audio files and multi track projects,

-how to import sound into Sountrack how/why import video, working with tracks, how do you set the scratch discs (where Soundtrack stores your media and files).

-Exporting single tracks and multi track mixes.