The MF-4 250 Bulk Film Back Part V

Though the magazine back operates on power from the batteries inside the motor drive, the AC/DC Converter MA-4, as an external power supply, is also available as an option. As the performance of dry cells deteriorates at low temperatures, you are advised to use a fixed-voltage power source, such as the NiCd Battery Unit MN-2 or the AC/ DC Converter MA-4, for shooting at low temperatures.

Battery Life

Life of the power source varies in accordance with the type of batteries you use. At normal temperatures, with manganese batteries you can shoot about 12 cassettes of film at approx. the guaranteed firing rate; with alkaline manganese batteries, about 20 cassettes; and with the NiCd Battery Unit MN-2, about 10 cassettes.

Firing Rate

The maximum firing rate in continuous shooting varies according to the power source in use, as shown in the table below.

Table 2
Maximum Firing Rate (fps) *
Shutter Speed	Manganese batteries	Alkaline-Manganese batteries	NiCd Battery Cell MN-2	AC/DC Converter MA-4
1/125 sec - 1/2000 sec	3.8 fps	3.8 fps	5.5 fps	5 fps
With Mirror Lock Up 1/125 sec - 1/2000 sec	4 fps	4 fps	6.0 fps	5.5 fps

During remote control operation with the Magazine Back MF-4, it might be useful to know when the film is at an end or when you have taken the desired number of shots you set on the frame counter. The External Signal Connecting Cord MC-14 is supplied for this purpose. By plugging one end of this cord into the MF-4's frame counter signal terminal and then rigging a suitable display system to the other end using the banana plugs, you can tell from afar when the subtractive frame counter reads "O."

In this example, an LED lights when the subtractive frame counter indicates "0".

Caution:

1) The terminal can control a display system of up to DC 20 V/200mA. Make sure not to apply more power than that amount to the terminal.
2) Always use DC power for circuits to be controlled by the terminal.
3) In connecting the External Signal Connecting Cord MC-14, make sure to connect the cord's black banana plug to the minus side of the power supp/y.

Convenient Accessory

50-Exposure Data Back MF-17

Designed exclusively for use with the 250-Exposure Magazine Back MF-4, the MF-17 allows imprinting of various data, such as year/month/day, hour/minute/ second, or a handwritten memo on the film. Compatible with any F3-series camera and requires a Types S focusing screen

Accessories

Remote Control Accessories

Remote Cord MC-12A with Button Release

For remote control up to 3 meters away, the MC- 12A has a,handgrip and trigger release button for convenient operation. Depressing the button halfway turns on the camera's exposure meter; depressing it further releases the shutter. After finger pressure is removed, the meter stays on for 16 sec., automatically turning itself off to conserve battery power.

Remote Cord MC-4A With plus and minus banana plugs, the MC-4A cord can be used to fire up to three motor-driven F3-series cameras simultaneously. For more details, please refer to the MD-4's instruction manual.

Radio Control Set MW-2 Provides interference-free remote control up to 0.7km away. Three separate channels allow three motor-driven cameras to be operated automatically.

Modulite Remote Control Set ML-1 Utilizes modulated light to control up to two motor-driven cameras automatically. Compact and easy to handle. Can be used up to 60 meters away.

Time Lag Shooting Accessory Intervalometer MT-2

Designed especially for unmanned time-lapse photography, work sampling, and lengthy time exposures, the MT-2 is a quartz-controlled solid-state timer of utmost accuracy. >A special delay switch is provided to activate the camera's exposure meter (and the autofocus function if an F3AF is used) either 2 sec. or 16 sec. prior to shutter release.

Maintainance and care for Magazine Back

1) Do not use the multiple exposure lever on the camera; when it is set to multiple exposures, pictures will be overlapped irregularly. When the lever is erroneously set to the multiple exposure position, simply return it to the original position before releasing the shutter to take normal pictures.
2) With the magazine back attached, do not use the rewind slides on the motor drive. If you do, the intervals between frames might vary.
3) Do not use cassettes which have been deformed or damaged through long use. They will cause malfunctions (such as varying frame intervals or overlapping of frames).
4) Because the rear cover is adjusted to each magazine back, take care not to deform the cover when you open, detach or replace it.
5) After loading cassettes, be sure to take up any slack in film to prevent overlapping of frames or inadequate film advance.
6) When the motor drive is used at temperatures of -20°C or lower, film perforations might tear due to fast winding speed, making it impossible to advance film. Do not expose film (cassettes) to low temperatures for long periods; load the cassettes in the magazine back immediately before shooting.