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After each reel is spliced and repaired, it is rewound through the film cleaner device on to the proper reel, which restores the reel to being heads out instead of tails (foot or end) out, and sent to the transfer room. Note: When using a liquid cleaner, view the rewinding film by reflected light to make sure it is dry again before it is wound up, or else the film may dry with "shoreline" marks on it. The cleaning fluid should have a small amount of wax dissolved in it to provide lubrication for smooth transport through the TVT-8 or through the customer's projector. A suggested amount is a lump of candle wax or beeswax the size of a pea ground up and dissolved in a pint (half litre) of solvent. Cleaning solvents that are widely used include methyl chloroform (toxic fumes), perchloroethylene (dry cleaning fluid) (toxic fumes), Freon TF (ozone depleting), or 91% or higher isopropanol (isopropyl alcohol) (flammable). There are also commercially mixed film cleaners with lubricant. Cleaning must take place in a ventilated area.
Theory of Operation
The conventional means of film to video transfer uses a projector with a specific number of shutter blades, attached to the mechanism and rotating with it. One blade is used to obscure the film while it is being pulled down to the next frame; additional equal blades are used to get the desired interruption rate, which must be a whole multiple of the video field rate. The blade complement might be either 2, 3, 4 or 5, depending on speed and video standard. That is, for 24 FPS (frame per second) transfers to NTSC (USA type) video the projector will have 5 blades. For running at 15 FPS you would have 4 blades, and for 20 FPS you would need 3 blades. This type machine will give more or less flickerless results at only one speed. Some old equipment requires that the operator frequently tune the speed to minimize flicker and complaints. Usually the running speed is quite inaccurate compared to the original amateur filming rate, leading to complaints. Flutter from the stretchable drive belt gives some residual flicker even if the speed is nominally correct. Takeup and rewind spindles are friction coupled and will eventually wear out. Lamps are expensive and can be hard to find, and frequently burn out. The unit has no, or a poorly performing, exposure correction ability, leading to complaints.
In the TVT-8J however the shutter is separate from the mechanism, permitting a selection of running speeds to be offered. These fixed speeds are crystal controlled, eliminating any need for an operator speed adjustment that can drift. Exclusive TCS technology also permits the running speed to be much closer to the original filming rate with a complete absence of flicker.
8mm and super-8 film was mostly shot at 16 or 18 FPS, while semi-professional users might have filmed at 24 or 25 FPS and a camera in bad repair or with weak batteries might have been running at about half speed. All of these films can be run at close to the correct speed.
NTSC (USA video) TVT-8 machines run at a precise 17.126 FPS in the Normal speed position, and 8.563 FPS at half speed and 25.689 FPS at 1.5x speed.
PAL (European video) TVT-8 machines run at a precise 16-2/3 FPS in the Normal position, and 8-1/3 FPS at half speed and 25 FPS at 1.5x speed.
It does take a few seconds for the mechanism and the shutter to lock together, so there can be jitter or travel ghosting until it stabilizes. Having about a foot of leader before the picture starts will prevent startup jitter from being visible. Some jitter or ghosting may be visible occasionally when running at half speed. Jitter and ghosting will be seen when running in Reverse as the shutter and mechanism are then not properly phased.
Individual direct drive torque motors are used for takeup and reverse/rewind reel functions, eliminating slipping clutches.
The light source is a laser-like special wide-spectrum white LED (light emitting diode) that should last for years. The output is of all wavelengths of visible light, and there is little or no IR (infrared) or UV (ultraviolet) radiation present to heat, fade or burn the film. Its brightness is controlled to automatically even out badly exposed film. (There is however no hope for the very worst film you will see!) The correction uses a choice of peak or averaging sensing, for optimum results from a variety of original moderate over- and under-exposure conditions. Peak sensing is recommended for most film. Average sensing is used for film that is strongly backlit (shooting into the sun) or that is dark and also has a light source (movie light or bright window) in the frame, or else is very badly overexposed. For critical transfer for fussy customers who are willing to pay extra, the brightness can also be set fully manually. This latter option usually means that the video must be edited later, to remove the overlap and startup jitter when previewing, starting and stopping the TVT-8 for each brightness correction.
Other Information
The TVT-8 has a "Mechanism Hours" timer to measure how long the main drive motor and the mechanism have been running. This only advances in the Forward and Reverse modes. The count is remembered without need for batteries when the unit is turned off. A time interval for servicing the drive motor and mechanism has not yet been established.
Service adjustments:
• After long use, the white balance of the LED and camera module could change. To reset the white balance, turn to "Still" and "Auto" without film but with an 0.8ND neutral filter in the light path, and observe the output signal with an oscilloscope or waveform monitor. Adjust the R and B (red and blue) pots in the camera module, for minimum chroma carrier, preferably from the S-video "C" output. Be very careful with the tiny pots as they are easily damaged or torn loose from the circuit board.
• Automatic exposure setting should be quite stable. Current optimum factory setting is .90 volts p-p with no film in the gate. Average film will then reach about 100 IRE while "all white" overexposed film will peak around 85 IRE. The "Average" setting is for .65 volts with no film. Voltage readings are peak to peak, and will be double if measuring an unterminated output.
• In case of replacing the timing belt, it will be necessary to reset the "Shutter Phase" selection. Adjust belt tension by plucking the belt and noting a low pitched tone. Ensure that the motor shaft is parallel to the mechanism shaft and that the belt is not riding the edge of a flangeless side of a pulley. While running film Forward, turn on the 10 switches one at a time in sequence. Pick the phase number that gives the best safety margin against the jitter and ghosting of other positions. Verify the selection by running at the other two speeds also. Often it is necessary to have a different Phase setting for the highest speed; this is done by movable connectors on the 11-pin header connector instead of using the switch.
• Focus, centering, magnification and all camera module settings are factory set and locked in place, and should not be disturbed. Camera setup switch settings are normally: 1 on, 2 on, 3 on, 4 off, 5 on, 6 off, 7 off, 8 off for NTSC units. Switch 3 may be turned off instead at the factory to suit some units. Switch 8 controls negative or positive output, which could be considered an operator setting for special effects or for experiments with negative film, however owing to the delicate and static-sensitive nature of the camera module this is best left alone. Changing other settings will cause malfunction or less than optimum results.
• In case of odd symptoms, first check the output voltage of the switching power supply modules. These should be 12 and 24 volts DC, ±5%. The voltage should change little no matter what settings are made to the operating controls. The 24 volt supply may sag momentarily while the drive motor starts running.
• If dust accumulates on the optics it should be removed with a clean camel's hair brush or air blower. Fingerprints must be removed immediately with lens cleaner and lens tissue, following the instructions included with them. There should be no need to open the light source module as dust will not normally collect inside.
• After long use, if the fixed plastic film guides show excess wear, they can be loosened, rotated 1/5 or 1/4 turn and re-tightened to get a fresh wearing surface. This can be done three or four times.
Suggested Sources of Supplies
Regular-8 and Super-8 400' reels in boxes of 200 pieces:
Tayloreel Corp. www.tayloreel.com 770-503-1612
Super-8 400' reels (8mm SMD component reels 7") in boxes of 100 pieces, item VP-A708-08:
Media Distributors, formerly Plastic Reel Corp (PRC) 800-929-1637 or (818) 980-9916 Attn: Mario in West, 800-772-4748 in East
White boxes for 7" diameter 1/4" audio tape reels in boxes of 180 pieces:
Protape Northwest 800-331-6107 and probably other suppliers
Regular-8mm Kodak White Movie Leader in 50' roll: # 163 5002
Super-8 Kodak White Movie Leader in 50' roll: # 191 0116
Super-8 Kodak White Movie Leader in dispenser box of 1000' (more economical): # 882 7362
Kodak Professional Film Cement 16 oz: #195 6176, 1 gallon: #195 6150, both plus $20 hazardous shipping fee. Kodak ordering toll-free number: 1-800-621-3456 (1-800-621-FILM)
Kodak Presstapes are now sold by Urbanski Film, (708) 460-9082 http://www.presstapes.com
Other suppliers may have editing equipment and sometimes have regular-8 leader. (Note: regular-8 leader in bulk is sometimes supplied in the double-8 width, and needs slitting down the middle to 8mm for use. Some kinds of leader cannot be cement spliced. Ask before buying. Slitters can be imported from Olex's web site at http://www.geocities.com/russiancamera/s8-equipm/s8-equipment.htm in the Ukraine.):
Christy's (equipment, leader, reels in small quantity) 800-468-6391
Neumade (manufacturer of rewinds, leader) 203-270-1100
MPE (equipment, leader, reels in small quantity) 212-245-0969
Starex (leader) 201-997-1555
FCA (leader) 818-845-7651
ECCO makes a film cleaning device that is mounted between a pair of rewinds. These are sold by several dealers. Film cleaning fluid is made by several companies or else you can use Freon TF, 99+% isopropyl alcohol, etc. with a small amount of wax dissolved in it for lubrication.
Helpful pictures can be seen in the Type M instructions here. Disregard the details about retarder posts as these are not present on the Type J.
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