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US/Canada Consumer Video Frequently Asked Question
Archive-name: rec-video/us-ca-consumer-video-faq
Rec-video-archive-name: us-ca-consumer-video-faq
Version: $Id: FAQL.US-CA.Consumer,v 1.5 1994/02/15 22:47:46 long Exp $
US/Canada Consumer Video FAQL (Frequently Asked Question List)
This release of the US/Canada Consumer Video FAQL (Frequently Asked
Question List) for this group (rec.video) also contains a 'Resource
Guide' for rec.video and VIDEOTECH readers. This FAQL does not cover
the subgroup rec.video.satellite. It also does not discuss software
(prerecorded material - such as cult movies - on tape or disc ). Many
sections have been revised (particularly in the area of laser video
disc - as I now have one - but for a comprehensive treatment of many
technical video subjects read Bob Nilands articles as they have much
more depth than we can/will go into here).
The primary purpose of listing commonly asked questions and their
(supposed) answers here is to cut down on 'noise to signal' content
ratios within rec.video. As such it is oriented towards neophytes and
is skewed more towards lowest common denominator systems rather than
high end equipment. It is also USA-centric and NTSC-philic.
This list does not attempt to track the ever changing names and prices
of consumer and prosumer video gear. Some rough trends and some
features to use when evaluating components are listed. I am debating
whether or not to list specific vendor recommendations or not. I am
looking for comparisons and listings of features/checklists for 27"
TVs, camcorders and vcrs to include here.
I am still counting on persons more knowledgable than myself in areas
(such as broadcasting technology, HDTV, BETA, video standards and audio
issues). Please send me corrections to answers and new questions you
feel should be included. Apologies for any non-objectivity you may
find in some of my answers. Help supply some of the ????? data!!!
^L
===============================================================================
TABLE OF CONTENTS
===============================================================================
QUESTION INDEX (enumerated index of questions)
GENERAL
BROADCAST TELEVISION (VHF/UHF/etc.)
CABLE TELEVISION (CATV)
CAMCORDERS, SEPARATE & STILL VIDEO CAMERAS
STANDARDS
VIDEOCASSETTE RECORDING/PLAYING ([S-]VHS/[ED-]BETA/[Hi-]8MM/0.75"/etc.)
LASERDISCS & OTHER VIDEO DISC FORMATS
AUDIO
^L
===============================================================================
QUESTION INDEX (enumerated)
===============================================================================
1. What are good prices ranges for video equipment today?
2. What do the terms 'letterboxing','windowboxing', 'Pan&Scan' mean?
3. What is MTS?
4. What is SAP?
5. Why don't Cable companies use the same VHF channels for local stations?
6. Cable company audits, detection, rules, legality.
7. My cable descrambler box Channel X (2/3/4) output vs. VCR tuner
8. Why do camcorder batteries hold less and less of a charge?
9. How good are consumer DC camcorder lights?
10. Define the terms : Lux, Zoom, and Pixels
11. "Which Camcorder should I buy?"
12. Sony V-series (450,000 pixels) vs F-series (270,000 pixels) models...
13. Are there Television monitors and VCRs that are compatible with...
14. Are there kits and plans for RGB to composite video, Y-C, etc?
15. Why do I get a scrambled mess when I try to copy pre-recorded tapes?
16. Is there a way to remove Macrovision?
17. What is an S-Video (aka Y/C) connector?
18. What are the upper resolutions of different video devices?
19. What is Dolby 'Surround' and Pro-logic Sound, SRS, THX?
20. What is a frame vs a field?
21. What is 'field motion'?
22. What does 'lines of resolution mean?
23. NTSC has 525 what???
24. What is CLV, CAV, PCM, digital vs. linear audio tracks, etc.?
25. What is the proper way to store video tapes?
26. Now I am totally confused as to how one should store video tapes...
27. Are head cleaners bad? What is the best way to clean heads?
28. What is HiFi sound and how is it recorded on tape?
29. "What is the story behind VHS (& the lack of SVHS) LP mode?"
30. What is the VCR+?
31. "Which VCR should I buy?"
32. Can you put a hole in VHS tapes to record in SVHS mode on them?
33. How come the RF output from my VCR/LD (one Channel 3/4/X) lacks MTS?
34. Is the video on laserdiscs (LDs) digitally encoded?
^L
===============================================================================
GENERAL
===============================================================================
Glossary - General Video Hardware
---------------------------------
BNC British Nut Connector
SCART European standard multipin connector. Can be used for both
composite and Y/C video input/output.
RCA jacks AKA "phono plugs"
RF jacks Radio Frequency coax hubs.
RF outputs from camcorders,vcrs,laserdisc
players, etc. provide combined audio and video as a
broadcast signal (usually on VHF channel 3 or 4). Lower
quality than baseband (RCA or BNC jacks) inputs/outputs and
Y/C connectors.
S-Video Multipin Connector with separate luminance & chromanance.
---------------
1. What are good prices ranges for video equipment today?
27" NTSC (US) TV, 400+ lines res, MTS/SAP, Y-C & multiple A/V
jacks (in&out), stereo speakers, ~180 ch. cable ready. $500
(assume tuners built into these)
2-head VHS VCR $150
2-head VHS VCR,HQ $200
2-head VHS VCR,HQ,HiFi $250
4-head VHS VCR,HQ $250
4-head VHS VCR,HQ,HiFi $300-360
4-head SVHS VCR,HQ,HiFi $500 JVC47000, Pana PV4167
6-head SVHS VCR,HQ,HiFi $600+
Hi-8 camcorder $1150 Sony CCD V801
Hi-8 palmcorder $900 Sony TR-81
SVHS (full or compact)camcorder $850
8mm camcorder $750
VHS camcorder $600
2. What do the terms 'letterboxing','windowboxing', 'Pan&Scan' mean?
Letterboxing
Putting the entire film frame (as seen in the original aspect
ratio, usually one where the ratio of the length of the
horizontal dimension over the vertical measurement is greater
than 1.33 to 1) inside the TV image (which is a more squarish
shape which can be expressed as 4/3) resulting in black
(although other colors are sometimes used) bars at the top and
bottom of the screen (the amount depending on the aspect ratio
of the film). You can see this often on MTV.
Windowboxing
Similar to Letterboxing except that there are vertical bars on
the sides of the inset image (as well as horizontal bars) as if
to prove 'this is the original frame as shot' similar to when
35mm and 2.5" negatives are printed with the original borders.
Compensates for overscan on overscanned sets. Seen on TNT.
2. What do the terms 'letterboxing','windowboxing', 'Pan&Scan' mean?
^L
===============================================================================
BROADCAST TELEVISION (VHF/UHF/etc.)
===============================================================================
Glossary
---------------
AFT Automatic Fine Tuning - TV/VCR station frequency lock
MTS Multichannel Television Sound. US stereo television
transmission standard. Up to 15KHz frequency response.
SAP Secondary Audio Program. 3rd audio channel provided in
conjuction
UHF Ultra High Frequency. US Channels 14-69.
VHF Very High Frequency. US Channels 2-13.
---------------
3. What is MTS?
It is a method of broadcasting stereo within the frequency
range reserved for each TV channel.
And less frequency range (to 15KHz) than VHS HiFi (up to 20KHz) --
it rolls off low, like an FM signal.
But videotape HiFi has all the problems associated with a compander,
e.g., breathing.
[credit Andrew Klossner [email protected]]
4. What is SAP?
It is a method of broadcasting a second audio channel (often a
translation into another language) within the frequency range
reserved for each TV channel.
^L
===============================================================================
CABLE TELEVISION (CATV)
===============================================================================
Glossary
---------------
AFT Automatic Fine Tuning - TV/VCR station frequency lock
CATV Community Antenna Television is the antiquated name for cable.
HRC A CATV Channel frequency allocation scheme.
IRC Another CATV Channel frequency allocation scheme.
MTS Multichannel Television Sound. US stereo television
transmission standard.
SAP Secondary Audio Program. 3rd audio channel provided in
conjuction
STD Another CATV Channel frequency allocation scheme.
UHF Ultra High Frequency. US Channels 14-69.
VHF Very High Frequency. US Channels 2-13.
---------------
5. "Why don't cable companies carry VHF stations on their cable on
the same frequencies they occupy in the air (VHF channel 3 on
VHF 3, VHF channel 8 on VHF 8) where they exist?"
Terrible ghosting. The cable company's signal lags the
leaked-in broadcast signal by an inch or two or horizontal
spacing. My cable company does this on one channel, and I hate
it.
[credit Andrew Klossner [email protected]]
6. And while we're discussing these (very interesting) topics, can
someone in-the-know briefly explain how, for example, a
rapacious cable company would detect 1) a "universal
descrambler" from a Radio Electronics article, 2) a second TV
connected in another room (believe it or not, some cable
companies have the unmitigated greed to want to charge EXTRA to
hook up a second TV in a bedroom, for example. Contrast this
with the phone company, which charges you for the LINE, not how
many phones you have connected to that line. But I digress...
;-) 3) How such detection can be circumvented.
- [email protected] (Scott Coleman)
[DISCLAIMER: Doing anything with the CATV coax coming into your]
[house other than connecting it to Cable Co. equipment or ]
[directly into ONE TV or VCR is considered illegal in most ]
[cable franchises (theft of service). ]
[This FAQL answer in no way endorses such behavior. ]
1) The R-E article box only accepts NTSC composite
video input, therefore no one would detect it.
It requires an external RF tuner if you want to feed
a channel into it (such as the RCA connector labeled
'video out' on the back of most VCRs).
2) TDR? (Time Domain Reflectometer - can show the
electrical topology of a cable) and or RF leakage
(backwash). Although many modern cable unscrambler
boxes are 'addressable' by the central Cable Co. office
many rec.video people don't believe they are 2-way
(is this a fallacy?). I am not sure whether the
cable co. can measure the load you are placing on the
coax cable - but if you are not using a powered splitter/
signal strength amplifier you will soon see that having 2
sets on one cable will result in a weaker/worse signal.
3) Pass the CATV signal through something that will
isolate, clean up, amplify and shield from RF
interference before distributing it to non-sanctioned
equipment??? Some splitters, or daisy chain the CATV
coax from VCRs to TV (or vice versa).
7. Why does cable descrambler box only output on Channel X (2/3/4),
rendering my VCR useless for recording premium channels?
Check and see if your cable box can be programmed or if you
can obtain a timer/remote for it from your cable co.
A VCR+ might make your life easier (elsewhere in this FAQL).
There are some TV/Monitors and VCRs that have multiple RF inputs
(and often multiple RF outputs) - these are sometimes labled
Antennae and CATV. You can have the unmucked cable coax connected
to the RF input labeled CATV and the output from the converter
box connected to the RF input labeled Antenna (assuming you aren't
using an antenna). In some case you are provided with an RF output
labeled 'decoder loop' that you can run to your converter box
(so that you don't need an RF splitter).
^L
===============================================================================
CAMCORDERS, SEPARATE & STILL VIDEO CAMERAS
===============================================================================
Glossary
---------------
AE Automatic Exposure (Iris, and possibly shutter)
AF Automatic Focusing (IR or image sharpness method)
AFM Audio Frequency Modulation - audio method for encoding on tape.
CCD Charge Coupled Device - one of the two different types of
solid state devices that replaced video tube technology.
IR Infra-Red. Light frequency below red in the (visible) spectrum.
Used by some AF systems (mostly older) and remote controls.
Lux Light Intensity measurement.
MOS Metal Oxide Semiconductor - one of the two different types of
solid state devices that replaced video tube technology.
PCM Pulse Code Modulation - audio method for encoding on tape. Rare.
---------------
8. Why do camcorder batteries hold less and less of a charge
after many uses? Is there anything I can do about it?
A memory pattern effect occurs (NiCad rechargable batteries
'learn' a memory pattern of past charge levels) but is somewhat
overrated. What most users see is really the fast discharge
rate of a NiCad (they will discharge much more quickly than
Alkaline batteries when both are sitting on a shelf not being
used).
You shouldn't really charge a NiCad frequently (if you are just
going to store it) or continually top it off after use unless you
need to use it for a full cycle again right way - you will just
be wasting cycles in the life of the NiCad (~ 500 - 1000 cycles).
On the other hand NiCads should NEVER be fully discharged
or reverse charged - this can shorten the life and even
damage the battery (some people use home-brew methods such as
paperclips and lightbulbs to short and discharge the battery).
Some posters in sci.electronics have suggested sparking the
batteries with a good jolt from a car battery to get them
to forget the memorized pattern. While this might work to
blast away the filaments of material shorting individual cells
it may result in an explosion and is not endorsed here.
An electrolytic capacitor can be used for this purpose,
be careful out there....
According to much popular wisdom (in the 'Info-Hams' mailing
list) many of the commercial products (D'Charger, etc.) are
harmless at best and shorten the life of your battery at worst.
Most new camcorder battery chargers (both the camcorder vendor
and 3rd party 'quick' chargers) stop charging them (overcharging)
after they are fully charged and some units perform 'pulse'
charging (preferred).
You need to be careful to use a charger that is appropriate for
your NiCad battery. Some 'quick-chargers' can build up gas
pressure quickly in batteries that are not designed for them.
Some full size systems and lights use sealed lead acid
(sometimes called gel-cells) that do not like full discharge,
they should be stored charged, and topped off to keep them at
full charge. Storing them discharged is bad for them.
[credit : [email protected] (Alan Larson),
instructions in my SunPak camcorder light battery,
"Hugh_E._Wells.ElSegundo"@Xerox.COM,
popular wisdom in the 'Info-Hams' mailing list ]
9. How good are consumer DC camcorder lights?
Most of the 20-30 watt DC units are only good for 10-20 feet.
And the batteries last for less than a hour (although you can
get Pro units that will last for 2 hours or longer they
generally require external battery packs).
10. Define the terms : Lux, Zoom, and Pixels
Lux - Light sensitivity. 1 lux is the light from one candle (?).
Most 1 lux cameras use electronic enhancement to obtain an image
(and the quality is not very good at one Lux - but hey, neither
is Ektachrome pushed to 1600 ISO!).
Zoom - Most camcorders have a zoom lens which can capture a range
of angles of view from wide through (what is considered) normal
to telephoto. The 'X' rating is the number of 'times' the
image is magnified (optically) at the highest setting (as in
binocular ratings). Most camcorders have 6x1 (low),8x1,10x1
or 16x1 (high-end) ratings.
Pixels - Picture Elements. Individual light gathering elements
(usually) on a chip. Analogous to 'rods' and 'cones' in our eye.
Better camcorders have over 400,000 pixels.
11. "Which Camcorder should I buy?"
The answer depends on many factors. Do you want the best
possible or the best price/performance in a particular class?
I would not recommend BETA to newcomers to the field unless
you are willing to put up with compatibility problems.
If you want to go BETA then you know what you are doing
(and up against). VHS has won the consumer VCR market,
even Sony makes VHS & SVHS equipment now and Sony's real path
for the future is in 8 and Hi-8 mm.
If ease of use is your criteria and you own a VHS VCR then you
should look at VHS or VHS-C (a 20 minute compact format)
camcorders - you can playback your cassette using your VCR.
If portability and weight (but not human induced jitter) are
your concern you might want VHS-C, S-VHS-C, 8mm or Hi-8.
If capturing high quality video for display now or in the
future is a concern then I would go with S-VHS[-C] or Hi-8.
If audio is a concern then look for a unit with HiFi Stereo
(Minolta 8-808. Sony V-101 has AFM. Olympus VX-H804 has
PCM Digital Stereo).
12. Sony spec says that V-series models have 450,000 pixels per
image while F-series models have 270,000 only. I am curious if
this difference matters since our VT (not HDVT) has a fixed
number of pixels anyway. Am I wrong or V-series models are
really meant for our grandson's- generation?
[credit: [email protected] (Zheng Zhu)]
The CCD on Hi8 picks up at about 410,000 pixels and the Hi8
systems records at about the same "level" (in quotes because
pixels are transmuted into horizontal lines of resolution but
it is about the same)... Regular 8 CCD (CCD is the
charge-coupled-device pickup "tube" of the camera) handles
about 270,000 pixels altho there are a few regular 8 CCD with
higher pixel resolution even if the taping system can't
actually record that high a resolution. Still results in a
better picture but nowhere near as good as Hi8.
Not meant for your grandson, meant for now, if you want to pay
the price (you also have to buy a Hi8-capable monitor if you
want to see ALL of the difference, but you will see some of it
even on a regular monitor or TV).
[credit: [email protected] (Jon Rosen)]
^L
===============================================================================
STANDARDS
===============================================================================
Glossary
---------------
HDTV High Definition Television. Megapixel display systems
proposed for the US. Japan and Europe have already selected
HDTV standards.
NTSC National Television Standards Committee. Video signal used
(broadcast,tape&disc) in the US, Japan and Latin America.
PAL Phase Alternate Line. Video signal used (broadcast,tape&disc)
in most of Europe (and the parts of the world where NTSC &
SECAM are not used).
RGB Video signal composed of separate signals for Red, Green &
Blue. Many computer monitors (especially higher resolution)
are often RGB.
SECAM Sequential Color and Memory. Video signal used (broadcast,
tape&disc) pour les hommes Francais et what used to be
known as the 'Eastern Bloc'.
---------------
13. Are there Television monitors and VCRs that are compatible with
multiple video signal standards (PAL, NTSC, SECAM)?
Yes. Contact Panasonic, Instant Replay (800-749-8779) and others.
14. Are there kits and plans for RGB to composite video, Y-C, etc.
and vice-versa?
Yes. Find an index for Radio-Electronics magazine at your
local library.
15. Why do I get a scrambled mess when I try to copy pre-recorded tapes?
(scrambled mess is defined as wavering lucidity followed by
total darkness). Am I going crazy?
No. This is called Macrovision. It is a copy-protection
scheme adopted by the home video industry which works by
varying the video signal gain level causing VHS VCRs to
track it into video oblivion.
16. Is there a way to remove Macrovision?
(because it bothers my TV/monitor with its flickering, of course)?
[DISCLAIMER: According to FBI warnings on most prerecorded ]
[videotapes, copying copyrighted material is illegal. This ]
[FAQL answer in no way endorses such behavior. ]
There are ads in the back of VIDEO & Radio-Electronics
purporting to do this. Some posters say the RXII works well
($49 in VIDEO). Some posters have asked about Y/C cable-ready
versions : there is now one advertised called the MT IIS
($99).
It is reported that some (older) Beta units are immune to
Macrovision. Copying to and then from these Beta machines is
said to remove it also. This is apparently not the case with
some (newer?) Beta units
[credit: Scott Coleman [email protected]]
Some camcorders are reportedly immune also and some posters have
claimed that they can fix up the signal by running it through a
monitor/tv with AV inputs/outputs.
17. What is an S-Video connector?
Also known as Y-C (and sometimes incorrectly referred to as
SVHS - which is a tape format) it is a cable and connector that
carries separate lumina (brightness) and chroma (color) signals
(vs. composite, in which both - and sync, etc. - are carried
on the same wire). This generally gives a better picture on
those monitors that support it (especially if the source is of
high quality & resolution). It is almost always a win to use
S-Video cable when you already have a high quality video signal
that has been separated into separate chroma and luminance and
want to carry it to another component.
18. What are the upper resolutions of different video devices?
( and broadcast standards? )
HDTV ????
IDTV ????
SuperNTSC????
Projection TV 800 (Good quality)
D-1 720 (specific since it's digital)
D-2 768
Video monitors 500-700 (Good quality)
ED-Beta 500+
Hi-8 425+
LaserDisk 425
CCD 4XX,000 pix 410-450 CCD camera with ~4[15]0,000 pixels/image
SVHS 400-425
HiBand Beta 400
Standard US TV 350
BI 350
3/4" -SP 330
Super Beta Is 330
Broadcast NTSC 330
8mm 300
Beta IIs 300
SuperBeta 290
CCD 2XX,000 pix 270-300 CCD camera with ~270,000 pixels/image
Beta II 250
VHS(SP) 240-250
Beta 240
VHS(EP) 220
Note that Bob Niland's evaluation of the new Sharpvision LCD
projection system has shown that you need to be aware of the
number of lines of vertical resolution (usually counted as the
entire frame: the sum of the interlaced field lines or around
250 x 2 = ~ 500 lines because of the persistence of the phosphor).
The Sharp LCD projector displayed both video fields, but in
only ~250 lines (both fields on top of each other, giving a
lower resolution image - more square LCD dots).
19. What is Dolby 'Surround' and Pro-logic Sound, SRS, THX?
These are methods of extracting spatial information from
encoded stereo audio channels (in some cases they can
be used to synthesize spatial relationships as well by separating
frequencies and sending them to different speakers).
See the following by Bob Niland ([email protected]):
Intro to Surround Sound Part 1 of 2 Revised: 18 Feb 90
Part 2 Revised: 06 Sep 90
20. What is a video frame vs a field?
NTSC displays two fields of video (each ~ 250 lines each)
interleaved to create the illusion of an 'image'.
21. What is 'field motion'?
When freezing a frame (2 fields) with a frame store or VCR, the
fields may have samples from different times. This can cause a
very visible flicker fluttering back and forth from the 2
positions.
My old Panasonic PV-1650 VCR did this. The Sony TR-5 camcorder
does this (which really ruins the advantage of the high-speed
shutter.) [credit: [email protected] (Alan Larson)]
22. What does 'lines of resolution mean?
The number of lines that can be shown...
The vertical resolution is fairly fixed around 480 - 488 for
NTSC, and is because there are that many lines shown.
The horizontal resolution depends on the frequency response of
the system, and is 3/4 the number of vertical lines that could
be seen on the screen. The 3/4 is a scaling to the vertical
size, so lines of equal width will result in the same number.
A quick relation is that there are about 80 lines of resolution
for each megahertz of video bandwidth. Since the performance
of consumer video equipment is such that the upper frequency
response is not a sharp point, this number is somewhat
imprecise.
[credit: [email protected] (Alan Larson)]
23. NTSC has 525 what???
The 525 figure is the ratio of horizontal to vertical
frequencies, and has nothing to do with lines of resolution.
[credit: [email protected] (Alan Larson)]
NTSC has 525 horiz. scan lines, but the horizontal res. varies
from VHS to SVHS to broadcast NTSC.... There are test patterns
available to determine horiz. res.
[credit: [email protected] (George Scott)]
24. What is CLV, CAV, PCM, digital vs. linear audio tracks, etc.?
Read Bob Nilands ([email protected]) papers on
LaserDisc topics. I have read the following :
LD Media Care & Repair Part 1 Revised: 31 Mar 90
Part 2 Revised: 28 Jul 90
Part 3 Revised: 05 Aug 90
Intro to Imported LDs Part: 1 of 3 Revised: 14 Sep 90
Part: 2 of 3 Revised: 13 Nov 89
Part: 3 of 3 Revised: 13 Nov 89
Intro to Laser Disc Revised: 29 Sep 90
Intro to Surround Sound Part 1 of 2 Revised: 18 Feb 90
Part 2 Revised: 06 Sep 90
Film/video 2-3 pulldown and "white flags" Last Revised: 06 Nov 90
Looking back: CED Revised: 14 Dec 90
(re: Capacitance Electronic Disc system)
^L
===============================================================================
VIDEOCASSETTE RECORDING/PLAYING ([S-]VHS/[ED-]BETA/[Hi-]8MM/0.75"/etc.)
===============================================================================
Glossary - Video Tape Formats
-----------------------------
8mm Videotape format promoted by Sony and others using 8mm tape.
Beta Videotape format promoted by Sony, much less prevalent than VHS.
D1 (aka D-1) Digital tape professional format.
D2 (aka D-2) Total digital tape professional format.
ED Beta Extended Definition Beta. Higher resolution Beta format.
Hi-8 Higher resolution 8mm format using higher quality formula tape.
HiFi Higher fidelity sound encoding on videotape. Usually
implies stereo channels. Up to 20KHz frequency response.
SuperBeta Improved Beta. How???
S-VHS Super VHS. Enhanced version of VHS dictating the use of high
quality tape formulation to store higher bandwidth signal.
Can only be played in S-VHS decks and VCRs with Quasi-S-VHS
(aka Modoki) mode.
S-VHS Mark II Super VHS with digital soundtracks (in addition to
HiFi and linear track(s)).
VHS Video Home System. 1/2" tape in cassette. NTSC and PAL
composite video versions. Standard promoted by JVC & others.
VHS-C VHS Compact. Smaller cassette holding 20 minutes of VHS tape.
Usually for small camcorders. Can be played in VHS players
with an adapter (some VCRs can play VHS-C w/o an adapter).
U-Matic 3/4" cassette professional videotape format. Dying.
------------------------------
Glossary - Video Tape Time Code Standards
------------------------------
RC Sony 8mm standard?
SMPTE Society of Motion Picture and Television
VITC Vertical Interval Time Code
-----------------------------
25. What is the proper way to store video tapes?
So that the tape is flat (and the weight is not on the edge of
the tape - or it will warp/buckle) - meaning the cassette
stored upright. And not on top of your TV, VCR, oven, car
dashboard or large
magnet :-)
26. Now I am totally confused as to how one should store video tapes....
One of the smallest sides of the cassette box should be on the
bottom and the other on the top:
+----+
/ T /
/ O / |
/ P/ |
BEST +----+ |
| | |
| L |(O)|
| A | | OR ...
| B | |
| E |(O)| +---------------------------+
| L | | +---------------------------+|
| | | | ||
/ | S | + | ||
/ | I | / | ( O ) ( O ) ||
/ | D | / | ||
/ | E |/ | GHOST - 1990 |/
/ +----+ +---------------------------+
/
+--------------------------------------------------------....
| Shelf
+--------------------------------------------------------....
27. Are head cleaners bad? What is the best way to clean heads?
The cheap abrasive tapes and solvents are reputed to be.
The Scotch cleaner tapes are supposed to be safe.
Take your unit apart (some units have easier access than others)
and clean the heads with a professional head cleaning kit or
take it to a professional for servicing.
28. What is HiFi sound and how is it recorded on tape?
HiFi sound (usually found on higher-end consumer VHS VCRs and
usually stereo) is a wider frequency response signal (to 20KHz)
- than normal linear VHS audio and MTS - with
noise reduction recorded in a magnetic layer under the video
signal before (or while?) the video signal is recorded.
Since is is not a separate track from the video track it cannot
be erased or redubbed without destroying the video track.
On NTSC Beta decks the HiFi signal is not in a separate layer.
It fits in the available bandwidth of the video heads.
[credit: Bob Clements, K1BC, [email protected]]
...2 head Beta is equivalent to 4 head VHS.
[credit: Richard Shetron <[email protected]>]
29. "What is the story behind VHS (& the lack of SVHS) LP mode?"
Before EP (sometimes called SLP) was invented by JVC some
manufacturers created a mode that was twice the playing time of
SP. It was never blessed by JVC (the VHS standards keeper) -
and they superceded it with EP (which has 3 times the playing
time of SP).
Supporting multiple playing speeds properly dictates
additional heads. Therefore 4 head players are better at
displaying EP mode tapes. ( 2 head machines use a compromise)
An additional set of heads would be useful to support LP mode
in a proficient manner.
This is why most 4 head machines don't have special effects
(freeze frame, slo-mo, etc.) in LP mode.
30. What is the VCR+?
It is a device that uses the functions your remote controller
(for cable converter, VCR) supports to simplify VCR
programming. Numbers available in some newspaper TV listings
are codes which entered into it will program a VCR.
31. "Which VCR should I buy?"
The answer depends on many factors. Do you want the best
possible or the best price/performance in a particular class?
I would not recommend BETA to newcomers to the field unless
you are willing to put up with compatibility problems.
If you want to go BETA then you know what you are doing
(and up against). VHS has won the consumer VCR market,
even Sony makes VHS & SVHS equipment now and Sony's real path
for the future is in 8 and Hi-8 mm.
If you want to play a wide variety of pre-recorded material
available at your local rental outlet you should purchase
a VHS or S-VHS VCR.
If you want to record live, or copy SVHS, Hi-8 videocassettes,
LaserDiscs and other high quality video sources I would
recommend S-VHS or Hi-8mm.
If you want to do both of the above you should get an SVHS
deck.
If size and/or portability is an overriding concern get a
Hi-8mm deck (although they are very scarce and most Hi-8
camcorders will function as players).
There are generally 5 tiers of VCRs, find the best price
and brand within one for your deal:
1. $150 Lower class: 2 heads, mono audio. Some play only.
2. $200 Lower middle: HQ w/either 4 head only or 2 Head with HiFi
3. $300 Middle Class: HQ, 4 heads, HiFi, MTS/SAP, CATV ready.
(Most popular currently, I can find these for $250
sometimes for people - such as PV4060, but for just a
few $$$ more often you can get the ....)
4. $500 Upper Middle Class: Either #3 VHS with digital special
effects or #3 in SVHS.
5. $750 Upper Class: SVHS, 5+ heads, digital special effects.
6. $X000 Rich: Professional SVHS & Hi-8 decks for editing.
32. Can you put a hole in VHS tapes to record in SVHS mode on them?
Yes. The best way is to melt a hole (drilling leaves particles)
- look at an SVHS cassette to see where to make the hole.
Not all tapes produces satisfactory (video) results (high
quality tapes are better).
33. How come the RF output from my VCR (one Channel 3/4/X) lacks MTS?
The tuners in both my VCR and TV have MTS and I am playing a
HiFi tape....
It would be expensive to produce and include RF transmitter
circuitry (for VHF channel X) that would do decent MTS (using
IF) (the normal RF baseband unit is cheap). Converting HiFi to
MTS will result in a degraded audio quality anyway. Use your
stereo (L & R) VCR audio outputs to hear HiFi. Hook them up to
your stereo if your TV doesn't have stereo audio inputs.
^L
===============================================================================
LASERDISCS & OTHER VIDEO DISC FORMATS
===============================================================================
Glossary
---------------
CAV Constant Angular Velocity - storage/access method for a disc
media where inside tracks contain the same amount of
data as outside tracks.
CD Compact Disc standard (5" and 3" versions),
usually refers to a disc with all audio track (70+ minutes).
CD-ROM Compact Disc - Read Only Media. 5" disc containg digital
binary data tracks. Often structured according to ISO 9660
and/or High Sierra (although the data can also be structured
as a SunOS Unix File System or Macintosh filesystem, etc.).
CD+G Compact Disc plus Graphics. Mixed audio and data tracks.
I believe the graphics are encoded in the data tracks (probably
digitally compressed) and are used in some 16 bit game systems.
CDI Compact Disc Interactive. Mixed audio and less than full
(aka CD-I) frame/motion video system just getting off the ground (Fall 91).
Competing with CDTV. Some believe CDI will be able to provide
VHS quality for 72 minutes with data compression.
CDTV Commodore Dynamic TeleVision - Another 5" disc format with mixed
audio, video/graphics and binary data. Competing with CD-I.
Currently less than full frame/motion video. Just released,
primarily for interactive video games and education.
CDV Compact Disc with Video. CD format with 5 minutes of Audio and
(aka CD-V) Video, 20 minutes of audio-only. Can be played in standard
(audio-only) CD players.
CLV Constant Linear Velocity - storage/access method for a disc
media where outside tracks contain more data than
inside tracks (by reading the outside tracks at a slower
speed almost the complete density of the disc is used).
LaserVision Licensed trademark for 8" and 12" laser disc standard.
---------------
34. Is the video on laserdiscs (LDs) digitally encoded?
No. This is a popular misconception that the LD manufacturers
often gloss over. LD video is analog. The original LD audio
tracks were/are analog also, most newer LDs have CD-quality
digital stereo audio tracks as well.
^L
===============================================================================
AUDIO
===============================================================================
Glossary - Audio
----------------
AM Amplitude Modulation - analog method of encoding audio
information (usually for broadcast) by varying the
amplitude of the signal.
Chace Licensed process of synthesizing stereo and surround
channels from audio sources where they didn't exist (by
separating and directing different frequencies to
different channels).
DBX Patented audio noise reduction method by ???.
Dolby(tm) Trademark and name of laboratory which licenses several audio
aka [)(] processing/encoding methods to preserve fidelity and reduce
noise.
Dolby Surround(tm) Dolby Labs Trademark and name of its process of
phase encoding spatial information using the 2 channels of a
(normally) stereo sound source.
Dolby Pro-Logic Surround(tm) Dolby Labs Trademark denoting a process
incorporating its standard (or meeting its criteria) for
decoding Dolby Surround(tm) into 5 channels (& speaker
placements): Center (dialog), Left Front, Right Front,
Left Rear, Right Rear.
FM Frequency Modulation - analog method of encoding audio
information by varying a (high) frequency carrier.
Q-Sound Method licensed by ????. Creates spatial sound
effects with only 2 speakers (using phase tricks).
Requires careful listener placement. One rec.video
reader reported he bought Madonna's Immaculate
Collection album set just to hear Q-Sound.
SRS Sound Retrieval System(tm). Hughes system for
creating spatial sound effects with two speakers.
Incorporated into some newer monitors/televisions.
THX 1) A licensed trademark from Lucasfilm that certifies
a that a particular theater meets their standard for
acoustic quality, audio equipment and speaker placement.
2) A method of mixing surround sound channels for a
film, with verification in a THX-certified theater.
3). A brand for (high-end) consumer audio/video gear
meeting Lucas specs.
[credit: Bob Niland [email protected]]
^L
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
[Scroll credits....]
Thanks for many answers, suggestions and posting gleanings to :
Bob Niland [email protected]
B.King@ee.surrey.ac.uk (Bevis R W King)
[email protected] (Mark Goldberg)
[email protected] (William R. Cruce)
[email protected] (Vidiot)
(Andrew Klossner (uunet!tektronix!frip.WV.TEK!andrew) [UUCP]
(andrew%[email protected]) [ARPA]
[email protected] (Alan Larson)
"Hugh_E._Wells.ElSegundo"@Xerox.COM
[email protected] (Tom Jack)
[email protected] (Ben Thornton)
[email protected] (Scott Coleman)
[email protected] (David Weaver)
Seng-Chou Timothy Chou <[email protected]>
Bob Clements, K1BC, [email protected]
[email protected] (George Scott)
Richard Shetron <[email protected]>
[email protected] (Michael Alan Schuster)
gpinzone@george.poly.edu (A1 gerard pinzone (ee))
[email protected] (Dave Haertig)
"Frank J. Wancho" [email protected]
John Mc [email protected]
[email protected] (Zheng Zhu)
[email protected] (Jon Rosen)
[email protected] (Larry J. Ingram)
Nick Sayer <[email protected]>
Bill Ranck <[email protected]>
[email protected] (Bill Vermillion)
[email protected] (Jerry Boyajian)
[email protected] (GREG KIMNACH)
[end credits.... fade to black]
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
Copyright 1991 H. Morrow Long
All Rights Under Copyright Reserved
Quoted and derivative material contributed by
persons other than the above author/editor
remains their intellectual property.
Permission is granted for the automatic redistribution of this article,
unedited, through the Usenet video newsgroups and the Internet
VIDEOTECH Digest. Permission is granted for each Usenet reader, each
VIDEOTECH subscriber and each person who received this article via
electronic mail from the author to redistribute it electronically, and
via hardcopy reproductions of this edition of this article for personal
non-commercial uses, and provided that no material changes are made to the
article or this copyright statement. Other uses of this material are
prohibited without the express written consent of the author/editor,
H. Morrow Long.
Disclaimer: Any views expressed here are mine and do not
necessarily represent those of Yale University.
H. Morrow Long, Mgr of Dev., Yale Univ., Comp Sci Dept, 011 AKW, New Haven, CT
06520-8285, VOICE: (203)-432-{1248,1254} FAX: (203)-432-0593
INET: [email protected].EDU UUCP: yale!Long-Morrow BITNET: Long-Morrow@YaleCS
WWW: http://www.cs.yale.edu/HTML/YALE/CS/HyPlans/long-morrow.html
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
----------------------------end of rec.video FAQL
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