Video Editing
Equipment - Cameras
For the purposes of this course our needs are minimal
In terms of equipment we can get away with a good deal. For most of this course we are assuming a shoestring budget. You can do a lot on a shoestring. (You can even break new ground: see http://www.richardleacock.com/leackessays.html)
Image-Stabilizing Equipment
Click on the image above to get a page on Image Stabilization (in a new window)Cameras
Digital, of course, is best
Then the word is
control, control, control.
Big, beautiful, manual control.
More than anything else you need control over two items, 1 - exposure and 2 - white balance, normally in that order. Exposure is almost always the single most important item you wish to be able to control manually.What If I Don't Have Manual Control (of my camera) and my "putt-putt" camera is all I can afford for now?
Don't put, put your camera down. Be happy! Use what you have. Limits like that make us work harder and concentrate more. True. Big budgets and all the great equipment you barely know how to run are not really the secret to good output. Count how many shoestring-budget directors with acclaimed films get big budgets finally and turn out snoozers. Work what you have. Work the content. In the example below of why automatic exposure is a pain, notice the framing work-around of changing where light and dark masses are in the viewfinder. 'Tain't Hollywood, but it can be good. - anyway!
Exposure control (usually aperture and in some cameras shutter speed) keeps your camera from trying to "help" you. Automatic exposure means your loose control over the image. Look at this series of still captures from video of Leonard Reed in his Hollywood office ( November 1999). Leonard Reed left Kansas City in about 1925 and spent a life in show business - he is still in the business and still coaches and gives workshops (he was born in 1907). Leonard is black, white and Choctaw and spent his career in black entertainment as dancer, producer, choreographer and more. He is given credit for originating, with partner Willie Bryant, the Shim Sham Shimmie in 1927 (a tap dance standard), was emcee at the Apollo and is the last living producer of the Cotton Club. Leonard and fight champion Joe Lewis were long time friends and went around the world playing professional golf tournaments as well as doing a stage act together, including the Ed Sullivan show.
Exposure Control - Automatic Versus Manual Automatic: The horrors of getting too much help. As you look at the series of captures notice the light and dark areas of the composition. Notice how changing the proportion of light to dark in the frame is noticed by the automatic exposure control. Although this shows you a compensation to try to overcome the loss of Leonard's facial detail when a very light area (the window) begins to occupy more space in the frame. This shows a clear need for manual exposure control in order to overcome the "helpfulness" of automatic exposure control. With manual exposure we would have had a much larger range of compositions without losing facial detail. 1 - start of clip. Black shirt helps balance light in window. Notice the relative percentages of light and dark in the frame. The eye sockets are a bit dark. 2 - camera moves very slightly upsetting the light/dark ratio. We loose Leonard's facial detail. 3 - A little more window. Leonards face is harder to see. Look at the change in percentages of light and dark in the frame. 4 - Now we are trying to correct for the autoexposure by changing the composition to include just the area most important to us - in this case Leonard's face. 5 - As we zoom into Leonard's face the camera begins to open up the diaphram. 6 - Closer yet. By this time the camera is getting the exposure for Leonard's face. But we really don't want the entire taping to be an Extreme Close-Up (ECU). 7 - Exposure is now okay for Leonard's face and we will attempt to change composition so we can back off. 8 - By putting Leonard's face in the corner (obsuring the lightest areas) we can have a little more surrounding area and still see our subject's face. His eye sockets also show more detail than #1. See this example clip of Leonard (16 sec) :: 56kb or 128kb connection (RealMedia) Manual: In this set of still captures from video the camera and the people are in flux but the camera's aperture, shutter speed and gain were all set manually and never changed all the way through. Look at how the exposures remain relatively the same regardless of whether the camera is pointed toward the windows (the source of light in the room) or away from the windows and into the room. Some exposures change because of the relative distance of the subjects to the light source (the windows) as they move within the ballroom. Unlike the still captures above none of the captures below go dark because of backlighting. Play the full clip below. See the full clip using manual exposure in a situation with a lot of movement for both camera and people. This is at Camelot Ballroom (151st street in Overland Park (Stanley)). There are large windows in the background providing most of the light in the room. Notice how the exposure, set for facial detail, remains the same even though the ratio of light and dark areas in the frame changes greatly.
(2 min 58 sec) :: 56kb, 128kb or 512kb (9.8megs) connection (RealMedia)About the piece. The Birthday Club was started in the early 90's. It is largely retirees, by invitation. They have a ball four times a year. Whoever has a birthday during that quarter pays that day and the rest dance for free.
Color Balance For Lighting
This is a comparison of White Balance Settings on a white paper. The lightsource in all cases is daylight, cloudy bright. Each white balance setting is a compensation for the spectrum put out by each type of light source. Using the right white balance setting produces correct colors. Light Source:
Cloudy Bright Sun
Use a White Card or white, flat surface, such as this one to set the camera's custom white balance setting. White Balance Set to Daylight Set to Tungsten Set to Flourescent Using a White Card White balance is how you achieve good color rendition. In the "old days" we used to buy indoor or outdoor film. Outdoor film was designed for the spectrum produced by the sun. Indoor film was designed for the spectrum produced by tungsten light (normal light bulbs). Tungsten is very red in color compared to the sun but we don't normally notice because the combination of our eyes and brain conspire to keep adjusting the way we see.
Our eyes are constantly making color adjustments. A white piece of paper as seen in the sun still looks white to us when we look at it under tungsten light. Unless we are looking at that piece of paper under something such as theatrical gels our biological systems are making corrections before we actually "see" the image. Cameras (having no real brain) are not able to make these adjustments so we have to conciously make those adjustments for the machine.
A camera whose white balance is set for sunlight will make a very yellow-red looking picture of a white piece of paper if the paper is in tungsten light. On the other end a camera whose white balance is set for tungsten light will make a very blue looking picture of the same piece of white paper when the paper is in sunlight.
When white balance is set, whether automaticaly or manually, the camera assumes that the "target" is neutral in tone, such as white, black or any gray in between. When you use a white card or a gray card to manually set the white balance this is true because you control the color target. The other option is one of the "presets." Setting the white balance option to daylight or tungsten or flourescent assumes the lighting for your scenes is identical to the preset. When the camera sets white balance automatically, the entire scene is treated as if all the colors in the scene were blurred together and then used as if the blurred colors were a gray card, regardless of the actual color. As a result, automatic white balance keeps changing.
The original version: not corrected and too red from the tungsten light. Second version, color corrected. Different mood and sense. Converting to B&W works best from a properly color corrected original. White Balance is the difference between a muddy picture and a clear picture. Above is a pair of tangoers, shot Fedora's 210 on the Plaza in Kansas City (George Brett has since wiped otu this classy restaurant for a sports bar and a sports gear store. The picture on the left is uncorrected. The picture on the right is color corrected in Photoshop. Notice the livelier look and the clearer detail. Below are two other examples.
Same location setting white balance for open shade (usually a Cloud icon in the camera.) Much brighter, livelier image. A few minutes later with white balance set for sunlight. Now we can differentiate the items in the picture. White Balance is the difference between a muddy picture and a clear picture. Above is a pair of tangoers, shot Fedora's 210 on the Plaza in Kansas City (George Brett has since wiped otu this classy restaurant for a sports bar and a sports gear store. The picture on the left is uncorrected. The picture on the right is color corrected in Photoshop. Notice the livelier look and the clearer detail.
The images on the top row are what you see and what the camera records. Except for the truck drawing, these are all still captures from video. The images on the bottom row are blurred versions of the picture just above. This is equivalent to the way a camera's exposure and white balance systems electronically "blur" the scene by sampling pixels for overall exposure and for overall color cast. In effect the camera treats the scene as a gray card. You can tell that each frame has different overall luminence and different overall color cast. This is the reason that automatic controls can wreck your picture and leave you with scenes which don't match each other. The truck drawing is overly warm for a typical outdoor scene but tungsten lit scenes (regular light bulbs) are very yellow-reddish. The point is that you need to have manual control over color and over exposure in a scene. Manually Setting White Balance
Although a "white card" is common any neutral-color (white, gray, black) target will do as long as the camera will let you make the adjustment. A gray card is a standard item in camera stores and handy to include within the scene to assist later in color balancing.
Small Trick: You can tune the balance so the picture looks very slightly warm by white balancing on a surface with a small hint of blue or cyan. A standard tablet with blue lines will do (lower right illustration).Digital is not the way to go for:
1 - Image stabilization - Use OPTICAL stabilization. Optical methods use an optical wedge method using the entire chip. Minolta developed a method of moving the entire chip. Digital stabilization works in part by using only a portion of the entire chip's image area. It is also subject to artifacts of movement in the frame when at times it can't determine the difference between subject movement and camera movement. Or when it tries to compensate for camera movement which the camera is moving with the subject.
2 - Zooms. Digital zooms are not really zooms. This is just a method for enlarging the central region of the image area with all the zaggies and pixellation artifacts you get from that, even though smoothing methods, such as interpolations, are added to make the digital "zoom" more palletable. Because a smaller area of the chip is used to produce the image the overall image suffers badly in term of resolution. Only optical zooms are real zooms (variable telephotos) and only optical zooms always use the full imageable area of the chips.
IEEE-1394 ( a.k.a. Firewire™ ) vs USB 2.0 vs USB 3.0 and eSATAThis is an Apple patent. Although it has an IEEE description Apple trademarked the name Firewire™. Sony implemented it's own version and called it iLink™. Everyone else is standard just calling it a 1394 connector. This is a fast serial protocol for moving data at a rate of 400 mips. USB 1.0 is a fraction of this speed. But, in numbers the USB 2.0 standard, at 480 mips is faster by 20-percent but in practice the actual speed of the USB depends on other CPU activity. A computer busy with other tasks can cut down the USB speed far enough that a 1394 connection can outpace it easily.
The IEEE-1394 connection runs independently of the computer's CPU and therefore is not affected by computer traffic which is not sent via the Firewire™. One note on 1394 dependencies: getting the data to the Firewire™ and saving the data from the Firewire™ does take CPU cycles but they are the same ones that would be needed to get data to or from a USB cable as well. That means Firewire™ is still the choice over USB 2.0 even though the un-impeded throughput figures for USB 2.0 are higher.
SATA is a disk-buss standard used for hard drives and runs at full system rate within the case. eSATA is the same buss but with a connector to an external drive, outside the case, usually a drive "dock.". This was the fastest method for data transfer until USB 3.0 came along wich pretty much matched the SATA transfer speeds, starting with hardware releases in late 2009 and early 2010. By the end of 2010 inconsistencies in the USB 3.0 implementation were ironed out and by mid 2011 you began to see a lot more USB 3.0 drives, even in the small USB-powered drives.
Image quality and Chips
Digital Cameras use three different types of image-sensor arrangements, Single-Chip CCD, Three-CCD Chips, Foveon chip and CMOS chips, single chips and three chips, sometimes called 3-MOS. The CMOS chips have all but taken out CCD chips as superior performers, especially when it comes to image "bloom." Because they take fare less electricity to run CMOS chips are also much better with batteries and run with less heat. At this writing no video camera uses the Foveon chip yet and only one still camera, the Sigma D9. In general three-chip cameras give better images than single-chip cameras. All things being equal in terms of shooting, shooter, equipment, etcetera, three chips always give better results than single chip cameras. But the difference is small enough that you may not see the difference without a cue card. In either case the single-chip cameras need offer no apologies.
All digital cameras pick up the image in three primary colors: red, green and blue. (If you were thinking that red, yellow and blue are primaries your are right, for paint and other pigmented color materials which are seen by light reflected from them.) Red, Green and Blue (RGB) are light primaries for colors seen by transmitted light. Television uses the RGB colors. Printing on paper with four-color printing uses the light primaries, Cyan, Magenta and Yellow. To cure purity problems black is added in printing to get proper color density and contrast. (CYMK color)
All we will use here will be RGB (red, green and blue) colors.
Film pictures exhibit grain. Grain is the microscopic structure of film and represents the smallest unit of the image in film. Depending on film, exposure, developer and development methods film grain can be very fine or coarse. Grain shows up in random order in the film's emulsion. That randomness in placement and size gives film subtle and smooth gradation (change rate between light to dark) which digital is still trying to come close to matching.
Digital pictures exhibit pixels. Pixels are the smallest image unit in the picture. They are always in a regular order regardless of whether they are created by rendering or directly from the image chip. Where color film has three emulsions each on top of the other, one for each color, digital chips have four pixel positions arranged in patterns of red, green, blue, green. These individual patterns are part of an overall checkerboard like pattern called a Bayer mosaic. The Foveon chip is the only chip in which the sensors for each color are arranged on top of each other physically, as with film.
The components of the single-chip Bayer mosaic pattern shown at the right. Notice that there are twice as many green pixels. Kodak scientist Dr. Bryce E. Bayer invented this mosaic pattern for color image systems about 25 years ago for both rgb and cmy sensors.This illustrates the RGB sensor.You expected that single-chip cameras would have red, green, blue pixels? Nope. Humans are more sensitive to green than any other color and so to get colors closer to what your eye sees the extra green sensor is used. But, unlike film, the sensors are not on top of each other (except the Foveon chip). What that means is that although each pixel position is a basic unit of the picture it is only recording one of the three colors at its location. To make up for that all single-chip cameras (keep excepting Foveon, of course) have to make up the other two colors at each pixel location by "interpolating." This means the camera's software looks at the colors around each pixel and uses their values to determine a value for the non-recorded colors.
That means that:
1 - Each red pixel position has to make up its green and blue.
2 - Each green pixel position has to make up its red and blue.
3 - Each blue pixel position has to make up its red and green.In the process of interpolating, the derived pixel colors are blurred (in software) before averaging. Although most single-chip color cameras use chips with the pixels in straight rows and columns, there are variations on the scheme. Fuji, for example, uses a set of honeycomb-shaped sensors in a tighter pattern. They call it a Super CCD. Sony introduced an 8 megabyte chip in fall 2003 in which one of the two green sensors (in a sensor set) is an emerald green, contending that this makes their color rendition more accurate. This is similar to the emerald green in Pantone's Hexachrome printing colors. Sony called their (then) new 8 meg chip an RGBE chip, rather than an RGB chip.
In a three-ccd or three-MOS camera the red, green and blue parts of the image are separated into three streams, red, green and blue. Then a single-chip for each color records all the pixel positions. The red, the green and the blue pixels from each chip at each corresponding pixel position are combined to form a single RGB pixel in the image.
The colors are separated by dichroic filters. Dichroic filters (also sometimes called dichroic mirrors) do not have pigments or dyes. Dichroic filters are clear coatings on glass which are the exact thickness of the wavelength of the light color they are designed to pass through. All other colors are reflected. That is the "DI" in dichroic, light is separated into two streams, one which goes through and the rest which are reflected. As dichroic filters are tilted at an angle to the entering light the length of a path through the coating layers changes meaning that the wavelengths of light which pass through and which reflect changes.
For an article on the net which directly compares the Foveon X3 sensor to Bayer-pattern sensors go to http://www.ddisoftware.com/reviews/sd9-v-bayer/. (this link opens in a new window)
"Real" Cameras v "Amateur" Cameras
First, let me tell you that you do not need a professional camera to produce worthwhile, even broadcast quality, output. Pro cameras give you extra controls and capabilities you really can't get at the consumer level, or even the "prosumer" level. But today's consumer cameras produce so much quality that you won't see the difference easily, if at all, on a regular television. Maybe not even on studio monitors. Even HD (high definition) is beginning to get into the act with a new HD camera introduction for less than $2,500.00.
In the mid-90's I bought a Hi-8 camera on the return shelf for $1,600. It was a bargain because its retail price was $2,500. The equivalent Hi-8 today is about $300 or even less. In 1990 I bought a Digital-8 for $1,000. It was a good deal. The equivalent Digital-8 today is about $400. My 3-CCD Canon GL2 cost me $2400 street and listed at $3,000. It is still up there for now but Samsung just introduced a MiniDV camera at $400. I have to confess to you that it is hard to see a full $2,000 difference in list price between my 3-CCD and my one-chip camera. I do see the differences in resolution and color depth but the visible difference is not huge.
Added later: Sony added a line of HiDef cameras in late 2008 which are superb at $3,200 and use three CMOS chips recording to miniDV tape in HDV format. Panasonic matched it with a $4,000 three ccd camera later to be a 3-mos camera with everything stored to SDHC memory cards. Sony then brought out the same CMOS camera storing directly to SDHC and SDXC memory cards for $3,600.
In the chain of items which are most important to picture quality the format's data specification is nominally first, matched closely by the quality of the recorder in the camera and the lens. The data specification is a fixed standard. Most lenses will exceed the ability of the recording mechanism so the recorder is usually the most variable quality-assurance link.
So don't get camera envy. I've met enough persons with expensive machines who got lousy results because they didn't know how to use them. What's more, that consumer camera is good cover and lets you get into more places than the expensive machine which can be very intimidating.
And for an interesting take on Hi-8 cameras (1993) and later innovations in equipment (pro and non-pro) check out the essays on Richard Leacock's site at http://www.richardleacock.com (or the essays directly: http://www.richardleacock.com/leackessays.html). Leacock was one of the original cinematographers credited with inventing Cinema Verite with Robert Drew. He started fliming early in his teens, during the 30's. His family knew Robert Flaherty. In the later 1940's he worked with Flaherty. Later he worked with Robert Drew on the 1960 documentary "Primary" which covers the Wisconsin Democratic primary between Hubert Humphrey and John F. Kennedy
