Vintage Video Conversion
- Recovery - Restoration
Convert Video to DVD
1/4 1/2 1 & 2 inch Open Reel to Reel Video Tape - Cartridge - Cassette
We support back to the very first video format - the 2" inch Quadruplex system, introduced in 1956 by the Ampex Corporation ®.
The first step in the conversion - restoration process is simply to get a tape to play and then to identify in which format the video was recorded. Some formats are easy to identify owing to their physical characteristics (VX Cartridges - Cartrivision etc) while others are a bit more difficult to ascertain. Half inch - 1/2" reel to reel media might have been recorded in either EIAJ-1, EIAJ-2, Skip Field, two variations of Pilot Tone, Concord 12 ips, Shibaden or Craig format - none of the formats being totally compatible with the other. Unless the tape was marked with either the format or recording machine model number (no one ever did in those days), it's anyone's guess as to which format it might be. With that said, experience dictates that 95% or so of the 1/2" inch reel to reel video tapes recorded after 1972 were either EIAJ-1 or EIAJ-2, owing to the large numbers of machines that had flooded the marketplace soon after EIAJ format was released in 1970.
The quickest way to find out which format, is to try and play them back first on a 1/2" EIAJ machine. If it's doubling the field rate, then it's Skip Field - if the audio is playing back too slow with no horizontal lock, then it's Concord 12 ips. If no H lock but the audio sounds ok, then it's most likely Shibaden or Craig.... Pilot Tone is best identified by simply trying the tape in an EIAJ-2 machine. If a waveform monitor reveals a color burst but there is no color, then it's most likely a Pilot Tone Format tape recorded on a Sony AV-5000A Pilot Tone format machine. Sounds a bit crude perhaps, as it's nothing much more than the process of elimination. Crude or not, it's proven the quickest and most effective method of identifying an unknown 1/2" reel format. 1/2 inch reel to reel tapes commonly came in two lengths. V-30H or V-31 in 30 minute lengths on a 5 inch reel, or V-32 in 60 minute lengths on a 7 inch reel (approx 2400 ft).. Thus the V-3x numbers give no clue as to the format of the tape. They describe the physical characteristics of the tape itself, but not the format or machine on which they were recorded. Likewise, Ampex 164, Karex, Irish etc.. for example, describes the manufacturer or type of tape product, but not the format which was recorded on it.
Some tapes won't be capable of even a simple playback, making format identification, much less recovery and transfer, impossible. The tape literally sticks and binds to the head drum, bringing the tape transport to a screeching halt. Vintage tapes exhibiting this common phenomenon suffer from what is known as the "Sticky Tape Syndrome" (also known as the effects of hydrolysis) - - which is an all too common a problem in tapes from the mid 60's to late 70's or so. Alas, all is not lost, as most tapes may be fully recovered by employing a process known simply as Tape Baking, whereby the moisture is driven out of the tape and the tape's binder layer is re-stabilized.
Once that is accomplished, the tape is then cleaned to remove debris and loose oxide and if it still exhibits sticking, then re-lubrication is called for. Then finally, the actual full playback and transfer can take place.
All video is processed through a broadcast Time Base Corrector that synchronizes the video to a stable reference (called house sync) that effectively strips off the unstable sync and lays down new stable broadcast quality sync onto the output video, including a stable reference color burst with proper "front porch", "back porch", "breezeway" and 9 cycles of color burst timing meeting RS-170A specifications. At the same time, the now stabilized video is routed to a Process Amplifier (proc. amp) where video level, chroma gain, chroma phase, and setup levels are monitored on a waveform monitor/vectorscope and reset to proper levels.
The destination or "target" can be almost any format: including VHS, S-VHS, MiniDV, DVCAM, DVD - or even standard computer files, to name just a few. Digital video may also be transferred to DLT tape, SDLT, 3480, 3490, 3490E,H computer tapes (both pc and mainframe platforms) or to DVDRAM. Optionally the video may be converted between the various world television standards. NTSC (US Canada & Japan), PAL, PAL-M, PAL-N (Europe) or SECAM (France and parts of Russia).
The video may be simply encoded to digital and cloned to a new digital format where the copy is an exact duplicate. This is by far the most cost effective transfer. The video may be optionally be digitally edited to remove breaks, unwanted scenes and damaged areas encountered. By editing, a wide range of special effects and scene transitions can be created for a truly professional result.
No one seems to address these issues, so I suppose this is what we'll tackle next......
Regardless of who does the vintage transfer, here are the quality issues to consider...
By today's standards, the video equipment and technology of even just 10 years ago, pales in comparison to what is available today.
Consider that even the least expensive consumer video camera on the market today, makes a far superior picture than the most expensive broadcast cameras and VTR's available back in the early to mid 60's. The only exception might have been the image orthicon tube which was huge, but had excellent resolution and signal to noise ratios (even by today's standards) owing to their large target areas. Later to come 1/2" vidicon tubes used in consumer/industrial equipment, bore none of these attributes of the orths. In stark contrast, they exhibited poor resolution, image lag, image burn, limited dynamic range and poor signal to noise ratios - plus a host of other maladies too numerous to list by today's standards. Cameras using the "tiny" 1/2" vidicon tubes were heavy, power thirsty, and always in need of alignment to keep them in top operating condition - or any operating condition as was often the case. The fact that they made a picture at all, was considered an achievement all to itself back then. The same can be said of the recording equipment as well. Today a tiny little MiniDV cassette recorder weighing a mere 1 lbs or less, has far superior resolution and vastly improved signal to noise ratios compared to any piece of vintage broadcast equipment weighing 2000 lbs or more, available at any price say 35 years ago.
One of the more noteworthy maladies, was that most of the consumer cameras of the day, did not have any DC clamping of the black levels. As background lighting would change, so would the overall gain.... Since there was no DC clamp to absolute black, the black level would routinely "wander" all over the place. To keep the amount of circuitry to a minimum, price reasonable, battery drain also to a minimum etc, something had to give, and lack of DC clamping to the black levels was one of them....
In today's digital age, we now take for granted high quality video, but alas, such was not the case in the early days of EIAJ, Skip Field and most other vintage formats.
The 1/2" EIAJ, Skip Field, Pilot Tone formats and virtually all consumer or industrial grade formats, were not broadcast quality machines.... They were low band recorders and at best were capable of only 240 lines of resolution (even when in their best of "moods"). Most cameras never maintained or serviced, produced no more than 200 lines of resolution.. They were marketed to the consumer and industrial users, and thus low cost was the prime objective. The only real consideration in those machines was that they be able to play a picture back on a standard television. Televisions by their very nature are extremely forgiving of poor sync signals and easily tolerate severe time base errors, and since the signals from these formats were never intended to be broadcast, "lots of corners were cut", as the only consideration was that it make a viewable picture on a TV.
VTR's by comparison, are much more sensitive to poor sync and time base errors. Consider that the capstan servo and rotating head drum on a recording vcr must lock to the incoming video by either speeding up or slowing down, so that an accurate control track as well as video tracks can be written correctly on tape. A vcr is a mechanical device, and thus due to the physics of mass and momentum, it takes time for the servo system to change it's speed to enable a stable lock onto the incoming video. If the incoming vintage video has time base errors (you can be certain it does) then the servos in the recorder might not be able to change their speed fast enough to accommodate the varying time base. The end result in severe cases, is that the servo "unlocks" - begins to "hunt", and the picture "crashes". (Naturally, TV's don't have this problem as mass and momentum isn't a factor).
Transfer of vintage video requires time base correction to stabilize the sync and timing so that the video can be recorded as well as make future copying of the media also possible (to make matters worse, time base errors accumulate from copy to copy if time base correction isn't employed).
Before delving in to what a TBC (time base corrector) WILL do, we'll first address what it WON'T do.
Contrary to what many may assume, Time Base Correction does not improve image quality itself. That is; it won't make video originally recorded at 240 lines of resolution now be 500 lines, nor will it make the picture cleaner and clearer. Poor signal to noise ratios will remain just as poor and actually degrade a small amount due to the digitizing errors of any TBC..... Rather, it lays down a stable broadcast quality sync without timing errors commonly found in vintage video tapes.
Early formats often had severe time base errors and sloppy sync signals to boot. Any video copied without being Time Base Corrected resulted in double the Time Base errors, as the errors on the source machine and destination or target machine were accumulative. If not time base corrected at the time of transfer, the instability would simply be recorded including any servo unlocks. This was often the case back then, as in those days, time base correctors were extremely expensive and few facilities had them. (our Adda VW-2 back then was $22,000 - and this is not a "typo" !). (The first one we purchased nearly sent us to the "poor farm" as $22,000 back in 1980 equates to over $62,000 in 2007 dollars).... Anyways, once the instability including time base errors are recorded, further time base correcting the now unstable copy will not eliminate the instability. The reason being that the jittering was recorded back when the non TBC'd copy was made and is now part of the program if you will. Thus the TBC will lay down stable sync for the copy to be transferred to DVD for example, but cannot undo the previous damage done when the original non TBC'd copy was made. That instability was recorded and became part of the program.
Now that we know what it won't do, what follows is what it will !
A TBC does resolve a common problem in attempting to transfer a vintage video to a current format, or where the vintage video is to be edited or processed through modern equipment. Most modern day video equipment is expecting a color burst signal, and will throw a tantrum (or go into "ignore mode") if a color burst is not found in the sync signal. Even though most vintage video was black & white and thus had no color burst signal, most current video capture cards, switchers, mixers and assorted other video equipment of today, is expecting the presence of a color burst (9 cycles of subcarrier reference). The TBC inserts a proper color burst on the original black and white video, to keep modern equipment "happy".
Most modern integrated circuit based TBC's will not lock or process vintage video, owing mainly to the severely deformed sync signals endemic to equipment of that era - plus the vagaries of aging tape. This is one case where a full rack size "vintage TBC" does a much better job than a modern piece of equipment. After all, it was designed to process the typical signals prevalent in it's day and is much more forgiving ! The composite sync tip coming off an old EIAJ machine for example, in many cases only slightly resembles a square wave. Modern day equipment isn't very tolerant of such sloppy signals.
The tradeoff comes in the case where a severe time base error or errors are encountered that are beyond what the TBC can correct. A high quality TBC will not allow unstable video to pass that it cannot correct.... period..... Thus it freezes the last good frame of video and remains frozen, continuously putting out a stable sync signal until such time as the bad area of video is passed. If Time Base Correction is not employed, then there's a good chance that the recording deck will completely lose sync and the servos will unlock and go on a "wild ride" - hell bent on tracking an impossibly wandering sync signal from the source deck. (read: no stable recording is possible until good stable sync is realized or video that can be corrected is encountered again).
A simple analogy would be how a typical VCR's servo system is similar to a car with sloppy, worn out steering. Both are slow to react to rapid changes. The simple concept of a VCR servo system trying to track a wandering video signal, is akin to attempting to drive a car with worn sloppy steering, down a pothole infested mountain road with numerous sharp hairpin turns, then attempting to negotiate those turns at say 70 MPH. Worn steering will make it impossible and it will inevitably result in one horrific, bone crunching crash - - tis' not a pretty site ! The TBC won't do anything for the servo systems' "sloppy steering" (the time constant of the second moment of inertia due to mass is an unbendable rule of physics) - but it will turn the video road into perfectly straight thru way and remove all the potholes, making it possible now to negotiate - even with "sloppy steering" !
Just how bad can things be ? ..... The good news is that the majority of vintage tapes exhibit few problems. Even so, some others may exhibit many - it's impossible to predict, as there are so many unknown variables. 1/4" Akai, 1/2" inch EIAJ, Skip Field, Pilot Tone & Concord 12 ips reel to reel tapes for example, are much more prone to these time base errors than are tapes from Quad machines. Most errors will be transparently corrected, but some ridiculously large errors will trigger a TBC freeze until the bad area of tape is passed. In the case of damaged H or V sync, slight picture shifts can result when the TBC left with no other option, shifts the picture to make it RS70A compliant... With old tapes often near the end of their playable life, (1/2"inch reel to reel formats in particular) these errors are more common and are to be expected. Naturally, physical tape damage can result in uncorrectable time base errors
In addition to vintage video not being the quality we take for granted today even when it was mastered, the very aging of the video tape itself causes further and sometimes serious image degradation. As the tapes age, they are susceptible to stray magnetic fields, possible high temperatures, moisture, moulds and a plethora of airborne contaminants. Over a period of 30 years or so, exposure to these effects start to take their toll. Add to that, most tapes have probably been repeatedly played on machines that were never routinely de-magnetized as part of a necessary maintenance program. Each time the tape passed over a slightly magnetized component in the VTR's tape path, a little bit of the program would get partially erased. Naturally the effects of this are sadly accumulative.
The first to go are the high frequency components of the image - the picture details and chroma parts of the signal if you will. The images will appear "softer". Color is usually the first to seriously suffer as the phase relationship to the color burst reference is critical. Color banding, phase/hue shifts, ragged edges and chroma noise increase dramatically as the tape ages. A few old reel to reel EIAJ-2 Color tapes will only be playable in Black & White due to severe degradation of the higher frequency color components. Also, as the magnetic information on the tape degrades, so does the signal to noise ratio. Noise levels increase, and the picture (on top of everything else) may start to have a "grainy" appearance with lack of detail.
Another factor adding to the troubles, was the VTR itself that was used to originally record the video. The record current to the heads is a critical factor. We want as strong a level as possible without overdriving the tape into saturation. Unless the recorder literally broke, no one ever bothered to keep the circuit adjustments at specification, and analog circuitry is all too susceptible to drifting out - or more accurately, it's more than just susceptible - it's a "given". Too low a recording current, and already signal to noise ratios were impaired the day it was recorded... Too high, and the tape was driven into saturation resulting in white clip distortion... Also, how much wear was on the recorder's video heads ? Video heads don't last forever, and as they wear, so does the quality of the original signal recorded on tape. Naturally, a partly clogged set of heads can have the same effect.
All of the half inch formats employed 2 heads and thus 2 sweeps of the tape to make one video frame. As the heads would wear, the output from each head would vary. Thus it was not uncommon for the output of head A to be noticeably different from that of head B, sometimes resulting in a perceptible inter-field flicker.
Thus there's lots that can go wrong...... The amount and degree varies sometimes even from tape to tape that were all stored together, and sometimes varies across the same tape. Note also that tapes recorded in any extended play mode, suffer the effects first and always to a greater degree. Simply too much information crammed in too small a space. ( read: never record in any extended play mode if quality or longevity is of concern).
Vintage Video is best viewed on a 17" TV/Monitor or smaller
Note again that most vintage video is low resolution at best. Back in the late 60's and up to the late 1970's, 27 inch TV/Monitors were not common or even widely available for that matter, and thus the 15 to 17" screen was at that time considered a full size TV & pretty much the norm. The Sony KV-1710 Trinitron was considered the top quality consumer TV in the late 70's, and even it did not have better quality direct audio/video connections to serve as a monitor - everything came in via the tuner. TV/Monitors with direct a/v connections were usually only available in the industrial & broadcast product lines......
Display technology has come a long way...... What may seem surprising however, is that vintage video doesn't look any better on a large hi-res monitor. In fact, it will often look a lot worse ! Today's hi resolution - large screen 27" TV's or HD panels will enlarge the low resolution video considerably, making the image appear very "grainy" as well as "soft". The higher resolution of today's TV/Monitors enlarges and displays in all it's stark gory detail, the inherent weaknesses of the vintage recording equipment and tape formats. If the same video is viewed on a smaller 17" monitor, the image will appear much sharper and with much less apparent video noise). View it on a 15" monitor, and you will be amazed at how much better it will look !
Once the visual information on the tape has degraded, restoring it to it's original pristine condition is not a financially viable option. Consider that a single hour of color video contains 108,000 separate frames. Restoration is a slow, tedious, frame by frame process requiring massive compute power and specialized software. Unlike film which is not susceptible to the ravages of image noise, video is a much harder image to restore. Try grabbing one frame of video and try fixing just a single frame in Photoshop (full version) using 3rd party noise reduction and image enhancement software. Trying to make it perfect will require around 12 minutes of raw computer processing to automatically fix some of the easier maladies and then almost having to hand "re-paint" the image to get it closer to the desired result. Also consider that the resulting corrections must be consistent from frame to frame to avoid any image flicker or "jumps". Take that lengthy endeavor and multiply by 108,000 and you'll get an idea of the complexity and costs involved.
Film is much easier to restore by comparison. It's major maladies are merely color degradation, scratches and registration errors - most of which can be comparatively easily resolved via automated digital processing. Even so, it's still a technically challenging as well as expensive endeavor in itself. Consider that Disney Studios spent 1.5 Million to restore "Snow White" (which was simple cell animation).
In the case of "Gone With The Wind", the 1998 restoration process was a daunting one. The most degraded parts of the film required special techniques. EDS Digital Studios (a Los Angeles based restoration company) spent more than 12 months digitally restoring the most seriously damaged parts of the film . EDS assigned 30 visual-effects artists to the project, who worked frame-by-frame to restore 18,000 frames - which translates into but 12 minutes and 30 seconds of film.
With the advent of new technology and increased computer power, perhaps one day true video image restoration could be inexpensively done on a desktop system. But today, that remains but an elusive dream.
Video restoration today, consists of salvaging what remains and making simplistic corrections to video levels, hue, saturation, time base errors and limited noise reduction (not elimination). In cases of serious degradation, just getting the old tape to play is technically challenging enough. The fact that some vintage tapes make any picture, is in itself an achievement.
Keep in mind that all the manufacturers' rate video tape as having a life expectancy of only 10 to 12 years if stored properly. Though many go 30 years (albeit with poor resulting image quality) the fact is that if the tape is older than 12 years, it's probably on "borrowed time". Each time an old tape plays, consider yourself "lucky"..... Also note that video tape was never meant to be an archival format in the first place. Though currently the best format to originate in, conversely it's the poorest storage medium in terms of life expectancy. Transfer to a digital format will at least stop further degradation before the video is lost forever.......
Read even more on Video Recovery & Restoration.. Click Here
Read More on Video Tape Life Expectancy. Click Here....
The human eye and the way our brains process visual information is nothing short of amazing. No film or video camera can come even close to the combination of sensitivity, resolution, wide dynamic range and the ability of our brains to automatically "white balance" any scene. From the ambient light and resulting color temperatures produced from a brilliant red sunset, to the soft low light of a full moon, our brains dynamically process the information and always get the colors right...... every time ! ......... Alas, such is not the case with even today's most sophisticated video cameras.
Early color cameras had a manual white balance procedure to be followed to insure correct color balance of the scene. Often times, the procedure was skipped, or changing lighting conditions occurred before a new white balance was made. Later cameras had auto white balance circuitry. Whether manual or auto, attempting to white balance on a scene with no true white in frame, would result in a flawed color balance. Other possible causes are faulty cameras, excessively hot or cold operating temperatures resulting in unpredictable camera operation, insufficient lighting, low battery or improper filter selected. Three tube cameras needed to be constantly calibrated using a grey scale logarithmic chip chart to ensure equal response from each red, green or blue tube, lest a color imbalance ensue.
Whatever the cause, the video in need of color correction will exhibit an overall hue of almost any color. It also may be exhibited only in the whites or sometimes only in the shadows, depending upon the nature or cause of the imbalance. Objects that should be pure white may have a color tint or the items that are shades of grey or black may have a sickening color hue. Color correction will offset the errors, thus re-balancing the colors.
Color correctors have saved many a production from having to be re-shot over the years. At best, re-shoots are an expensive endeavor, and at worst, the footage was a one time opportunity that can't be repeated. Thus color correctors perhaps have saved countless lives of producer's seriously contemplating suicide.
The color corrector is a valuable tool in the restoration of vintage video, where color imbalances are common.
In the case of transferring film to video tape or DVD, a color corrector can easily re-balance most color imbalances due to either film degradation, or as often the case, a sloppy transfer having been made where no color correction or proper white balance was employed. Though we do not offer film to video transfers, we can color correct the video, often making an dramatic improvement.
The control track, written by the recorder when the video was recorded, is akin to the sprocket holes on standard movie film. Simply put, the control track lets the capstan servo system know where the video tracks are exactly written on the tape. Without a reliable control track, the video tracks will not be found and the video heads start mis-tracking down the guard bands on either side of the video tracks written to tape - the guard bands are sort of like the "dead zone" and act as a buffer between the video tracks, so that one field doesn't start interfering with the other. Effects of mis-tracking appears as a large horizontal band of noise, that may or may not, roll through the picture. Note that a TBC won't cure tracking errors - only time base errors....
Some old tapes have weak degraded control tracks - making accurate tracking difficult or sometimes impossible for portions of the tape. Though our decks are kept clean & peaked for the maximum control track signal, there are limits to what they'll be able to read. Our decks cannot read a reliable control track signal where there is hardly anything remaining to be read. The other reason for mis-tracking is the physical distortion of the tape itself. Any dimensional instability of the tape results in displacement of the control track as referenced to the video tracks. Tape edge damage is usually due to a tape being played in a machine out of alignment and will invariably result in tracking errors. The more a tape is played, the more stretching it is subjected to.
The environmental conditions in which the tapes are stored plays a major role in the long term dimensional stability of the tape. It takes very little hardly perceivable warpage or stretching, to wreak havoc on trying to achieve a stable playback. After many years, the dimensional stability of the tapes degrade and the tape starts to deform, depending on the internal stresses on the wraps of tape. These varying stresses are due to uneven moisture absorption/evaporation causing the tape to swell or contract unevenly with the varying trapped humidity between the wraps. Over the years, the tapes "stretch & twist" plus expand & contract in an attempt to even out the internal stresses. Unfortunately, the deformities are not a constant, which often results in widely swinging tracking errors on playback.... A "penetrating glimpse of the obvious" perhaps, but the longer the forces have to act, the greater will be the deformity. Sadly, many vintage tapes haven't been re-tensioned in over 30 years. This is the reason that it is widely recommended that any tape (either reel or cassette based) be fast-forwarded and rewound at least once every three years to relieve any internally built up stresses on the tape)
The vast majority of vintage video tapes do not exhibit this problem to any serious extent, but a few others will. Now you know why !
Flagging appears as a horizontal bending of the video at the top of the screen. In severe cases it can affect up to the top 15% or so of the image, however the bottom 85% is not affected. It is caused by improper tape tension either when originally recorded or on playback. The tape tension is also called Skew, and synonymously, Flagging is also sometimes referred to as Skew Errors. Upon playback, it's easily corrected by adjusting the skew of the playback machine. If however the skew was not within spec when the video was originally recorded, no amount of adjustment later may be able to eliminate it.
Most open reel machines have variable skew adjustments. When recording, a control rod resets the skew back to the proper tension for recording. Many VTR's were never maintained, and as the felt pad wore on the supply reel, the tape would be recorded with insufficient back tension. As a result, the tape would sit so loose or the head drum, that as the rotating heads first made contact with the tape at the lower edge, the tape would be physically lifted from the head drum. As the heads would sweep further up the tape, the tape would settle down. This would result in sever flagging or even vertical instability due to distortion where the vertical sync was recorded.
Minor skew errors can often be completely corrected via use of a TBC. If the errors were so great that even the vertical sync signal was affected, then a TBC will make things worse by introducing severe vertical jitter or freezing frames, since it needs to "see" at least an undistorted sync . Is those cases, the flagging is there to stay. Luckily, it rarely affects the view-ability, but can be aggravating nonetheless...
The quality of the video recovered depends also on the quality of the equipment used to record the video in the first place. In the case of EIAJ, Skip Field and Pilot Tone reel to reel, many video tapes were recorded using a Sony AVC-3200 (studio) or AVC-3450 (portable) monochrome camera (the companion camera to the Sony AV-3400 Portapack which was a portable 1/2 inch EIAJ-1 VTR). These cameras were most popular in the early 70's for non-broadcast industrial recordings.
Both used a single vidicon tube and were usually equipped with a 3:1 manual zoom lens which often was in dire need tracking and back-focus adjustments. (image blurs as the camera operator zooms in or out necessitating a re-focus). Since the cameras all employed the vidicon tube, the cameras had very limited dynamic range and were susceptible to a noticeable image "lag", especially in poorly lit areas. Neither were the cameras capable of making hi resolution images. In many cases, if the camera was able to resolve 200 lines, that would have been a "banner day" - - and that was when it was operating in its' "best of moods".
There were numerous adjustments, and the circuitry of the day was susceptible to drifting (read: most cameras were constantly in need of a good "tweeking".) There was no microprocessor controlled auto iris (or auto "anything" for that matter...), but rather exposure control was performed manually by way of opening or closing of the iris. Since most field crews didn't have even so much as a waveform monitor when recording in those days, video levels were pretty much guesswork. If the image started to burn or bloom on the monitor, they'd back off a stop; and if muddy, they'd open the iris up a bit. Without a waveform monitor, proper exposure was mostly a hit or miss type of affair. Panning across uneven lighting with a fixed iris, often resulted in video "mud" or image burns. Although some cameras had auto gain circuitry, none of the AVC series had DC Clamping of the Black level. Thus as the auto gain changed with the varying lighting, so did the black level (and it could change significantly). Light sensitivity was also poor. The early cameras needed LOTS of even, intense light to make a good image. (Consider that many consumer cameras today will make an acceptable picture in candle light !). Early productions or shoots that took place out of the studio environment usually had inadequate lighting unless shot outdoors in sunlight.
Add to that, the simple electronics, lack of accurate phase lock timing loops and non existence of digital integrated circuits. Specs for NTSC monochrome video were 30 frames/sec - 525 lines/frame for a horizontal scan rate of 15,750 lines/sec. The simple r-c timing circuits of the early cameras usually resulted in something other than 525 lines/frame. Sometimes 523 or 527 or so - depending on it's "mood" and operating temperature. Frames rates also varied out of NTSC specs. Good enough for playback on a TV, but not for a successful transfer to DVD where the video must meet NTSC timing specs to even be capable of being transferred. The TBC will either add or subtract lines to make it 525, but sometimes at the expense of a slight 1 line vertical jitter if the camera was dithering between line counts. (The TBC will either add or subtract a line to MAKE it 525 lines/frame...... when on the "edge", the correction often shows up as a one line vertical jitter).
Add to those woes is the fact that vidicon tubes did not operate long at peak performance. After 200 - 300 hours, tube emission would start to drop. Instead of a crisp image with good contrast, the image would slowly degrade commensurate with the age of the tube to the point where the image would appear "muddy" and often out of focus - even with adequate lighting. Replacing a vidicon tube was a "pricey" affair necessitating the camera go to a repair facility for tube replacement and re-alignment. Most users didn't bother....
The early consumer/industrial formats such as EIAJ, Skip Field, Pilot Tone Shibaden and Concord 12 ips were never intended to be broadcast. The design goal was only that the cameras and decks make a viewable picture on a standard TV. Naturally, a LOT of corners were cut to contain costs. Those were the "standards" of the 60's & 70's..... The main consideration when shooting consumer or industrial grade video in those days was that the equipment be capable of making a picture on a TV at all. That in itself was quite an achievement back then ! Other "trivial" matters weren't even considered or often times even possible, owing to the relative simple technology of the day and what the target market could afford.
Quadruplex on the other hand was a high band broadcast format with much more circuitry. Naturally, they were huge and very expensive. These machines were used solely in a controlled studio environment where video levels and such were properly monitored, as well as high end broadcast cameras were used. Thus quad format tapes suffer from far fewer of the maladies that are evident in the 1/2 inch reel to reel EIAJ tapes for example.
In cases where the tape has been physically damaged, there is not much that can be done, other than to transfer whatever remains in whatever shape it is in. A simple crease or score may be exhibited by a snowy horizontal band. Crinkles usually spell disaster, as nothing is where it should be and not surprisingly, what results is usually un-viewable.. Edge damage often results in a bad control track reference, making it impossible for the servo system to lock onto the video tracks.
Even if the images are barely watchable, it's usually a short period of time before the tape will become completely un-viewable. The transfer may not be "pretty", but a priceless poor quality video is still far better than no video...
Almost anyone can make a transfer from a modern day cassette format.... Just pop a cassette in a modern deck and hit "Play" - it's not exactly "rocket science". Vintage formats on the other hand, pose their own unique challenges.... not only in maintaining vintage equipment, but also the knowledge of how to best recover unstable and aging vintage video. It probably explains why there are but a handful of us seriously engaged in this challenging endeavor.
The older a tape becomes, the more troubles as briefly noted above, will be encountered. Tape degradation is an on-going process that will ultimately render the tape unplayable. The only hope in saving the material is to get it transferred. Transferring to a digital format stops further degradation dead in it's tracks, and in effect, opens the doorway to video "immortality".
Using the proper techniques and equipment, most video is fully recoverable, and although no where's close to the quality of video shot today, the images from tapes 30 years old or even greater, usually make for a perfectly viewable picture. The quality of most tapes is surprisingly good considering their age and the technology of the day !
There is a wealth of information on this site as it pertains to the vintage video formats. I hope this has been informative.
Last Modified: July 29, 2008
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