home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Fresh Fish 9
/
FreshFishVol9-CD2.bin
/
bbs
/
hard
/
cvts-1.0.lha
/
CVTS
/
CVTS.doc
< prev
next >
Wrap
Text File
|
1994-03-08
|
45KB
|
838 lines
The Complete Video Test System
Dave Muse
Version 1.0
March, 1994
INTRODUCTION
The Complete Video Test System is a collection of twenty test
patterns that you can use to evaluate, troubleshoot, or compare video
equipment. Many of our tests are unique, and can be found nowhere
else. This text will explain the tests in clear, non-technical
language, and show you how to use your Complete Video Test System to
make purchasing decisions, adjust your equipment for optimum
performance, or just demonstrate the quality of the system you have.
It is important to remember that, just as the strength of a chain
is limited by its weakest link, the results of tests performed on your
video system can only be as good as the poorest piece of equipment
that the video signal must travel through. I will point out, as we go
along, what types of problems with your system could result in low
scores on the various tests.
In addition to helping you evaluate your system, I will be
telling you how to make adjustments to your TV or monitor to improve
it. These adjustments are optional, as you may have to remove the back
of your set to get some of them done. Many sets have an interlock to
disconnect the power cord when the back is removed. You can defeat
this by removing the end of the cord that is attached to the set's
back and plugging it directly into the chassis (if you observe how the
back goes onto the set, you will see how it connects the power cord to
the chassis). THIS INTERLOCK IS DESIGNED INTO YOUR SET FOR A REASON!
Working in back of your set with the power on can be dangerous! Be
careful not to touch anything except the controls we are talking
about, stay away from high-voltage areas (the high voltage cage and
the picture tube), work with one hand only on the set (and keep the
other one away from anything metal), and sit or stand on a dry,
insulated surface while you work (like a cushion or carpet). Last and
most important, don't sue me for your electrocution! I've just warned
you, and you're on your own!
CVTS is available as software that runs directly on an AMIGA
computer system, or as a videotape playable on any of several types of
VCRs. If you have the option, better results will be obtained by
using CVTS directly from your AMIGA system rather than from tape.
Most of the tests, however, will work just fine from tape with no
compromise in function.
USING YOUR SOFTWARE
When using the software version of CVTS, remember that these
tests are designed for NTSC television systems. This means you will
need a genlock or NTSC encoder if one is not built into your system.
The black-and-white video output on the AMIGA 500/2000 will work
with a number of the tests (the ones that do not require color), and
in fact I recommend using this output for as many tests as possible,
if your genlock or encoder is not a high quality unit. The tests you
will need color composite output for are: COLORBARS, COLOR PURITY,
CHROMA RESOLUTION, CHROMA NOISE, COLOR CRAWL, and the MULTIPLE TEST.
Black-and white output can be used for all the remaining tests, even
when you are looking for the color symptoms mentioned and making the
requested color adjustments. Users with monochrome only video output
that do not wish to obtain an encoder can purchase a tape to run the
color test patterns.
If you want to try some of the CVTS tests on your RGB computer
monitor, be my guest. All you'll prove is how incredibly superior RGB
is to NTSC!
The tests consist of pictures and animations displayable with any
IFF picture/animation viewer. An easy way to tell whether a given
test is designed for a TV or a VCR is to look at the icon. A drawing
of a monitor is represented on some of the icons, and a video tape on
others. A test that is intended for both will have a drawing of a
monitor with a VCR on top. One test, the camera resolution chart, has
a camera lens represented on its icon. This video camera test is the
only one that needs to be printed before use. The easiest way to
print it is to run Graphicdump (it came with your Workbench, in the
utilities drawer) and display the test. It could also be loaded into
a program like Deluxe Paint and printed from there. This test is
specifically designed to work well regardless of the quality of the
printer you have.
GUARANTEE?
The video tests that make up CVTS are designed for informal use
by both video professionals and non-professionals alike. CVTS is not
and cannot be designed to the same rigorous technical specifications
as professional test equipment, and results from the former should not
be given the same weight as results from the latter. I can't
guarantee that you will make correct video purchasing decisions just
because you own CVTS - as much as I hope and think you will. I can't
guarantee that you won't damage yourself or your video equipment in
the course of using CVTS (please be careful)! You'll have to assume
the full risks for these things. So what do I guarantee? I want you
to be happy with CVTS, so if you've purchased this package or anything
else from me and you're not pleased with it, you may return it for a
refund at any time.
DISTRIBUTION NOTICE
CVTS is copyrighted. This package is freely distributable, but
not public domain. Distribute it as you wish - just keep everything
together, this document included. Since this version of CVTS is
shareware, you would (hopefully!) feel an obligation to contribute
money to use it. Instead of a guilt-inducing diatribe from the author
about $$, how about this: If you like this product and plan to use
it, I hope you will consider purchasing a colorbar viewing filter,
printed manual, videotape, or other product from me. They will
enhance your copy of CVTS and make it more useful to you. Purchasing
any product (see the included order form) will register you and put
you on my mailing list for updates to CVTS. Yes, new tests and
improvements to existing ones are in the works. I am also quite
receptive to feedback. If you spot something wrong, don't curse me -
write me a letter instead!
THE TESTS
Here is a brief description of each test and instructions for its
use.
COLOR BARS
Everybody has seen the color bar test pattern before. It's a
standard test signal, used throughout the television industry, for
adjusting video signals. Professional television monitors frequently
have a switch, labelled "blue only" , which is meant to be used with
the color bars for precise adjustment. By using the blue viewing
filter supplied with your kit, you can adjust your TV or monitor the
same way professionals do. Here's how it works:
(1) Find the control labelled "Color" on your set (it can also be
called "Chroma" or "Color Level").
(2) Display the Color Bars on your monitor or TV, then look at the
screen through your filter. CONTINUE TO USE YOUR VIEWER for steps two
through five. The odd-numbered bars should appear blue, while the
even-numbered ones are very dark, almost black. Observe that each blue
bar has a smaller blue box just underneath it. While adjusting the
COLOR control, compare the smaller boxes of the FIRST and LAST bars to
the larger bars above them. When they are exactly the same brightness,
the COLOR control is set correctly.
(3) Find the control labelled "Tint" on your set (this control is
sometimes called "Hue" or "Phase").
(4) While observing the two MIDDLE blue bars, adjust the TINT control
so that the smaller boxes underneath them are the same brightness as
the larger bars.
(5) If the smaller boxes underneath the FIRST and LAST bars no longer
match the bars above them, then go back to step one and repeat these
adjustments.
(6) Put down the blue viewer. Look for three small black bars in the
bottom right quadrant of your screen. If you can't find them, turn
your brightness up. When your TV is properly adjusted, the third
(rightmost) of these boxes will be just barely visible - and the oth