UIST 2003 Hints for Making Good
Videos
Introduction
Video is a great way for showing
reviewers and the conference audience the look and feel of your application.
Much of the work at UIST involves highly interactive applications and examples
that are difficult to capture using words and static images. To misquote the
cliché, if a picture is worth a thousand words, then a good video can be worth
many more still.
Although papers must stand on
their own, submitted videos will be sent to reviewers as supporting
material. These hints serve as a guide describing how to produce an ideal
video for UIST. Please do not be intimidated by the guide. Videos are viewed
only as supporting material, and authors of accepted papers will have the
opportunity to prepare a more.
Anyone who has done video editing
and post-production knows that it is a surprisingly time consuming business.
However, it's garbage-in garbage-out, and if you don't have good content or
message, the best video editing in the world will not help it that much. So,
make sure that you thoroughly "proof read" your video. The time will
be well spent, and it will probably still only require a fraction of the time
that you have to spend anyway on video production.
So, how does one determine if the
content is good and the message clear? We suggest you "proof read" or
usability test your video. You can start off by testing your script with
colleagues and friends. Is it interesting and understandable? Next you may want
to storyboard your video. Do the cuts and transitions make sense to people, can
then visualize how it will look? As well as being useful for usability testing,
the storyboard should be an important part of your planning process. Next you
should do rough cuts of the video. Do people want to see more talking head shots
or less? Is the demo clear? Is the pace too fast or too slow? Are there any
particular usability problems with specific segments of the video?
We hope that the hints we provide to you help you make an interesting and
understandable video.
The tips we provide are organized into the following
sections:
-
Planning Before You Shoot
-
Pacing
-
Content: Exposition and Presentation
-
Equipment
-
Camera Basics
-
Lighting
-
Sound/Audio
-
Editing
-
Capturing and Recording information on Computer Screens
-
Final Thought
Planning Before You Shoot
Before shooting begins, prepare a
detailed script of the video and rehearse it thoroughly. Your rehearsal should
include shooting the scenes as they are walked through and then reviewing what
you have shot. When you perform your
review consider looking at the image on a TV monitor rather than the viewfinder
of your camera. Reviewing what you have captured will tell you a lot about the
changes you can make so your video images are clear to the viewing audience.
Questions you may want to ask yourself while you watch your video are:
are there distracting background noises that can be eliminated such as turning
off the soda machine or shooting when the heating system is not running? Are all
the things you want in view in view? Can
the lighting be changed to better show the items of interest?
Videos require much more planning
and preparation than most people think. Find someone who doesn't understand what
you do, sit them down and give your demo to them before the camera arrives. It's
good practice in speaking and helps to clarify the delivery of your ideas. If
your demo involves a larger group of people, it will be especially important to
have the major scripting and production bugs worked out beforehand.
When you have completed your script
It is generally not appropriate
to hire professional actors to appear in your video. (However, professional
readers may be appropriate for the audio, see below.) Usually the most realistic
and convincing advocate of an idea is the person responsible for the research.
However, make sure people who appear on camera speak naturally, and don't look
like they are reading. Remember that the value of video is as a way of
demonstrating things, so keep talking heads to a minimum unless they are an
intrinsic part of the event or process being described
Pacing (Really Important)
The video medium is different
from either a lecture or demonstration. The pacing of a videotape presentation
must be appropriate for concentrated presentation through a TV monitor. Too slow
a pace is as common as too fast. A recording of a live demo often will appear
too slow. Storyboard your script to compose a sequence of scenes that tell your
story. Check that transitions
between each scene give the viewer a sense of continuity and that the transition
style does not distract the viewer from the video content.
Content: Exposition and Presentation
The exposition style of your
videotape presentation will greatly affect its impact. Use the multiple modes of
communication that are available simultaneously in videotape. Always explain
(briefly perhaps) what is about to happen or what is most interesting. Display
screens have few natural navigation aids. Tell the viewer where to look and what
to look for. You might speak aloud the directions to the camera operator, such
as ``if you zoom in on the top right corner of the display'' which will help the
viewer orient themselves. Make your point once, and make it effectively; avoid
being repetitious.
Seek variety of image: switch
between face, screen, hands, and slides to keep the viewer's interest. Always
start out with an establishing shot, which shows the context of the subject
and/or group. This might be a wide shot of the group in a meeting room, a
split-screen shot of users in different locations, a wide shot of a meeting
participant at the computer, or of the entire computer screen. This helps the
viewer stay oriented. Periodically return to an establishing shot to keep the
viewer from getting confused.
Each shot should be visually well
composed. Get as close to the subject as you can. As a rule of thumb, place your
subject so that it takes up two thirds of the screen. Avoid having the subject
in the exact middle of the screen. Pay attention to the background and colors;
the eye is drawn to the most brightly colored part of the scene. Make the
lightest and brightest part be the point of interest.
Avoid visual distractions, such
as idly moving the mouse. Fades to black can be used as transitions between
scenes, but they should not be overused. A full screen fade usually indicates a
change in subject, time or place, and can be confusing when used elsewhere.
Visual distractions can be caused by patterns such as plaid and strip shirts.
Encourage speakers to where solid colored shirts or blouses to avoid the
perception of shimmer in the video image.
Equipment
Use the best quality equipment
that is available to you. The final production quality of a video depends both
on the quality of the equipment as well as the training and experience of the
video maker. If you have access to a high-quality production studio and trained
personnel, use them. However, production quality can be achieved with the
commercial equipment found in most universities, companies, and what is now
available for home video production.
Camera Basics
Too much movement is
a common problem with many videos and is a problem that can easily be avoided by
adopting some simple camera techniques. Using
a tripod can give a stable image by removing the potential for “camera
jiggles” and can also ensure that the image seen appears level. Minimizing the
use of panning, zooming and other moving shots can
also help. Use the pan and zoom capability to get your subject in appropriate
view prior to the shoot. When you do use pan or zoom, begin and end each moving
shot with a static shot.
Lighting
Carefully consider lighting when
preparing the area for the shoot. Avoid using several different sources of
lights when shooting. It can throw off your colors and has the potential to have
the subject of interest appear to dark or too bright during the course of the
shoot. When reviewing your video look for distracting dramatic shadows on walls,
poor contrast between the subject and the background, or ghoulish shadows on
faces, a common occurrence with overhead lighting. Using directed diffuse
lighting could help solve some of these problems caused by poor lighting
conditions. When recording information from a computer monitor check for glare
and adjust your lighting to remove or reduce the glare as much as you can.
Many cameras enable you to do
white balance adjustments. Make use
of this feature as it can greatly enhance the contrast between your subject and
the background.
Avoid using different sources of
lights when shooting, as it will throw off your colors. For example, avoid
taping in a room with both natural and artificial light sources. The white
balance setting adjusts the camera to your lighting. When setting, focus the
camera on the color that you want to be filmed as white. This could be a sheet
of white paper or the whitest color in the scene, depending on the effect you
want. Avoid having too much white in a scene because it will make all your other
colors too dark. Monitor your video levels. White levels should be at 100 units,
and black levels should have a pedestal of 5 to 7.5 units. If possible, include
30 seconds of color bars and tone at the beginning of the tape. The color bars
must be generated by the camera or editing equipment. Color bars copied from
another tape are worse than none at all.
Sound/Audio
The quality of the sound can impact the quality of your
video. As with light there are
simple techniques that you can employ to add to the quality of your video.
Often the camera microphone does not give adequate sound.
To over come this problem, the sound can be recorded separately, however,
synchronization of the video with a commentator can often be a problem when
adding the “voice over” to the video. Consider
using an off-camera microphone that is directly fed into the video camera used
in the shoot. It can give you the
quality sound you need and remove the need for you to add a voice over and
synchronize the voice with the images. Removing
background unwanted background noise is helpful.
Sudden and repetitive sounds often can be avoided by asking those in the
room of the shoot to not rustle paper, clear their throat or
jingle the change in their pockets. Doing
the shoot between on cycles of the room’s heating/cooling system is another
possibility and shutting windows to eliminate street noise.
When doing a commentary near a computer —
using ``talking heads,'' try to do these with the computer off, or with the
microphones arranged so that the computer noise is not picked up. If
you have a sound meter available USE IT to perform sound checks during the
shoot. The sound level should
constantly stay at the middle range level. Avoid
sound spikes above and below the mid-range level.
Finally, many successful videos
use trained readers for the dialogue, which you can find by calling acting
schools or radio-stations. The final dialogue should have clear should
enunciated words and the style should be neither too soft, slow, or fast.
When you listen you will know when it is right.
OH – turn off ALL cell phones!
Editing
As best as you can edit the
original raw footage or stills and when all your editing is complete make your
master. Loss of quality is less likely to occur with digital video but even then
you must be careful with special effects and compositing.
Capturing and Recording Information on Computer Screens
Because of incompatibilities of
resolution, refresh rate, and interlacing, it is often difficult to get good
shots of computer screens on video. Two ways to capture the image: by pointing a
camera at the screen, or using a scan converter or video encoder to translate
the computer's signal directly to an NTSC or PAL signal or videotape. You will
probably need to experiment to find the best way of capturing screen images on
video.
Most people will film the screen
with a camera. In this case, darken the room to enhance contrast, and set your
white balance to match the white of the screen. Position your camera to avoid
rhomboidal windows from the curved face of the display. You will have to pan
around the screen to show different parts, because the video will usually not
show the entire display in sufficient resolution to read text and see the
graphics. If you have problems with one camera, you might consider borrowing or
renting different cameras to see if you can obtain better results when shooting
from the screen.
Try to find a display that has a
refresh rate that is compatible or synchronized with the NTSC video camera rate
of 30 frames per second (25 frames per second for a PAL video camera). Most
displays are not, so you will get a crawling refresh line on the tape. In this
case, try to wait until it is not visible before each video segment. If there is
a continuous beating or flashing on the video, this means that the refresh rates
are completely incompatible, and you should probably not make a video of that
screen. Sometimes shooting the image from a flat panel (LCD) type display,
can remove some of the problems seen with the traditional computer monitor.
If you have hardware that
converts your computer signal to NTSC, you can record directly from your
computer to tape. A major problem with this is that single pixel horizontal
lines will flicker badly (in fact, all odd number width horizontal lines will
flicker somewhat). Most modern scan converters filter this out. Check to see if
your scan converter has a filter to reduce flicker.
Some scan converters have zoom functions.
Use this feature advisedly as you would use the zoom and pan on a camera.
If your display is color, limit color saturation to 75 to 80% and choose
hues carefully, especially reds, to avoid exceeding the NTSC color bandwidth.
Final Thought
Making a video is hard work, but
as any attendee of UIST will tell you, a good video is worth its weight in gold.
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