DE1955563B2 - AUTOMATIC FADE-UP FOR CINEMA RECORDING CAMERAS - Google Patents

Description

automatically switched on when the polarity of the motor is reversed is actuated and after the specified time dos switching means.

For such automatic cross-fading, several embodiments are conceivable that z. B. be able to distinguish whether the switching of the camera motor is effected directly by the aperture blades or with the interposition of a relay. Furthermore, the scheduled time generator can either be of a purely mechanical type or electronic type.

If an electronic time generator is provided, it is particularly proposed to train it in such a way that that it is activated as a timer when the fade button is pressed and when the polarity is reversed of the motor switched from timing to timing means being provided to ensure that the time formed is the same as before measured time and the motor is stopped at the end of the established time.

These and other features of the subject matter of the invention can be seen from the drawing in which the Invention is shown in three different embodiments. It shows

1 schematically shows a cinema recording camera in section,

F i g. 1 a schematically shows a switch with an actuating button,

F i g. 2 shows an embodiment in which the shutter blades switch the camera motor directly and a mechanically working time generator is provided,

Fig. 3 shows an embodiment according to FIG. 1, at to which the aperture blades switch a relay, which in turn switches the camera motor,

F i g. 4 shows an embodiment in which an electronically operating time generator is provided.

The housing 1 of the cinema recording camera has a lens 3 on the front plate 2. A film cassette 4 is housed in the interior of the housing, in front of a partition la with a picture window la '. A sector shutter 5, which is driven by a camera motor 7 via a shaft 6, rotates in front of the picture window.

The objective 3 is equipped with an objective diaphragm, not shown, in the form of an iris diaphragm. The rotating lamellar ring of this iris diaphragm is extended in the direction of the housing and inside the housing formed into a ring gear 8. The ring gear 8 and thus the diaphragm lamellar ring is connected via a pinion 9 rotated by a shutter motor 10 which is part of the exposure control circuit. The ring gear 8 is also provided with a pin 8 ″ that rotates with the ring gear and with two electrical ones Toggle switches 21, 22 interacts, which he actuates in the closed position of the diaphragm.

In addition, a release contact 25 is housed in the housing 1, the circuit of the camera motor 7 is closed when actuated, and a fade contact 32, by means of which the shutter motor 10 is directly connected to the battery, not shown. Both contacts are operated via buttons 25 a, 32 α, as in F i g. 1 a shown, which are accessible outside of the camera housing.

In the housing 1 a mechanical time generator is also housed, which consists of a gear wheel 13 with saw teeth on its flat side. This flat side faces a switching disk 14, which also has Sögezöhne on its flat side. Both discs are pressed together by a spring 15. Α and by a screw 66 on the corrugated "6 and a worm wheel 17 with shaft 17, S gear 18, the gear wheel is entrained in all contusions of the motor 13, both advantages and in return. When moving forward, the saw teeth slide off one another with their flat sides, but when moving backward, the switching disk ίο 14 is taken along and rotated by almost 360 °. At the end of this rotation, it meets with its switching arm 14 β on an interrupter contact 19, which lies in the circuit of the motor 7, the power supply is thereby switched off. When the camera moves forward, the switching disk 14 is then taken back into its starting position. These components thus represent a mechanical time generator that allows the camera motor to run back only for a precisely defined period of time. 2 shows the simplified circuit of the first exemplary embodiment of the invention. The camera motor 7 is connected to a current source 20 via changeover switches 21, 22 and a transistor 23. The latter is controlled by a control amplifier 24, which is used to regulate the speed and in whose power supply line the trigger contact 25 is also located. This type of triggering and speed control is known and is therefore not described further. The circuit also contains an exposure regulator in the form of a Wheatstone bridge, which consists of the photoresistor 26 and the fixed resistors 27, 28, 29. In the diagonal branch of the bridge there is an amplifier 30, the output of which leads to the shutter motor 10, the other pole of which is grounded. Depending on the current strength in the diagonal branch and the polarity of the current resulting therefrom at the output of the amplifier 30, the shutter motor runs to the right or left and adjusts the shutter.

In the connection between amplifier 30 and motor 10, two contacts are included. First a measuring contact 31 (with which a contact 31 α is coupled) and second a cross-fade contact 32. The measuring contacts 31, 31 α are to be actuated in a known manner before the camera is triggered so that the shutter has already adjusted to the prevailing object brightness at the beginning of the scene and in this way flash effects can be avoided in a normal scene. In the event that the user forgets the previous actuation of the contacts 31, 31 α , these contacts are also interconnected with the release contact 25 in the manner of a sequence switch, shown by the dashed line 25 a.

The shutter motor 10 can be separated from the exposure regulator by means of the fade contact 32 and be connected with its one pole directly to the power source so that the motor in the Starts the closing direction of the diaphragm blades and closes the diaphragm completely.

The diaphragm motor 10 drives the toothed ring 8, which is firmly connected to the rotatable lamellar ring in the lens diaphragm, in the manner already described. His pin 8 α acts on the changeover switch 21, and this operative connection is shown in FIG. 2 indicated by the dashed line 8 b . In the feed line to the camera motor 7, which is effective when running backwards, is the breaker contact 19, which is from the mechanical time generator 13, after a predetermined time of the reverse

fes is opened and thereby the camera motor with the fade contact 32 also the contact

the power source disconnects. 33 opened so that the relay drops out and thereby the

The circuit described above works with toggle switches r21, r22 back to flow reversal.

a cross-fade in the following way: switches.

To initiate the dissolve, press 5. In the examples described so far, the user is the dissolve contact 32. This means that the rewinding time is independent of the fade-out time. In the diaphragm motor 10 is also shown with its second F i g. 4 shows an exemplary embodiment in which the terminal is connected directly to the battery 20, namely the dimming time is measured and the rewinding type so that it is limited to this value in the sense of a shutter closing time. So one is turned. In the position in which the diaphragm allows the two scenes to overlap very precisely. Except when it is closed, that is to say when the dimming process has ended including the components already described, the pin 8 α hits the exchange of the relay R contains the circuit according to FIG. 4 selector switches 21, 22 and actuates them. By switching to an electronic one instead of the mechanical time generator, the polarity of the camera motor is reversed and the watch time generator runs. The latter consists of a reverse connection, with the film being of course also a constant current source, which is the resistors 35, 36, which is transported back. Diode 37 and transistor 38, and further

When the camera reverses, the measurement of a capacitor 39 begins, at the two poles of which a mechanical time generator is running, namely a toggle switch r 21 and r 22, connected to the switching disk 14, turns almost 360 ° and then hits. These changeover switches are also contacts with their switching arm 14 α on the interrupter contact 20 of the relay R, so that the polarity reversal of the capacitor clocks 19. After the changeover switch 39 is switched over with the polarity reversal of the camera motor 7, this interrupter contact 19 is also present that falls. The power supply of the time generator he camera motor 7 in series, so that when it now follows from via the contact 33, which is also opened here together switching arm 14 α , the current flow to the mo- with the fade contact 32 is operated, gate 7 is interrupted : The camera will be stylish- 25 Will the dissolve by closing the Translated. To carry out these three processes: Dimming contact 32 initiated, the turn begins, reverse travel, shutdown, the shutter needed to close. At the same time, however, the cross-fade contact 32, the contact 33 of the time measuring circuit is put into operation via user but only once, the other processes followed. This is a resistor 35, 36 and the diode 37 is the aforementioned consensual improvement over the prior art of the constant current source, which now has the capacitor 39 long technology, in which each of these processes is charged individually. Two more had to be introduced in the circuit. dene transistors 40 and 41 are blocked.

For the fade-in at the beginning of the new scene, if the shutter now runs into its end position, the user must, after previously pressing the button of the 35 she, as already described, let go of the relay contact rl, cross-fade contact 32 and the relay picks up, and the contacts 21, 22 thus reverse the polarity of the shutter motor again with the two motor 7. At the same time, however, the connection controller has connected the trigger button on the output bar r 21, r 22, the capacitor 39 to polarity. Press the transit release contact 23 again. By pressing the sturgeon 41 is now no longer on its base short-release button, the release contact 25 and 40 are closed, but receives the charging voltage of the Kon-measuring contacts 31, 31 α closed. As a result, the capacitor 39 runs as a reverse voltage. Then, however, the shutter motor is on again, with the pin 8 α still locked and the transistor 40. selwitches 21, 22 released, so that the motor 7 discharges again while the camera is running backwards and can now start running forward. During the above-described constant current source running the capacitor, the switching disk 14 then also returns to 45 39. If the capacitor is completely discharged and the initial position is back. If the polarity is reversed, the constant current flows into the

The execution transistor 41 also functions in the same way. This becomes conductive, as does the

example according to FIG. 3. However, transistor 40, which blocks transistor 23, switches here. In order to

the pin 8 α not directly the changeover switch 21, 22, the camera is shut down. The diode 42 in a circle

but these are, denoted in Fig. 3 as r21, r22, 50 of the time generator has the task of the basic emit-

Switch of a relay R to compensate for the voltage of the transistor 41 in this embodiment, so

example is also provided. The pin 8 α scarf that the entire during the dimming process in

tet the relay contact r 1 instead, so that the rede capacitor charge stored during the

lais attracts and in turn the changeover switch 21, return is removed again. As a result of that

22 actuated. With the button for the fade 55 for charging and discharging the capacitor the same

contact 32, a contact 33 is coupled here, the constant current is used, is ensured,

in the power line to relay R. Will that the return time of the camera exactly equal to that

Fade contact 32 is closed, so the fade-out time is also After opening measuring contact 31,

the contact 33 is closed and the relay can be triggered contact 25 and fade contact 32

pull when the pin 8a closes the contact rl. 60 puts the entire circuit in its idle state

On the other hand, it is relocated after the camera has been shut down. The start-up takes place as already in FIG. 2 loading

if you let go of the crossfade button, you will write.

1 sheet of drawings

Claims (5)

Pentium claims · ■ 9th in the interior of a fade-out arbitrarily in a general claim. , schlosaen.Steliung can be brought; at the end of the 1. Automatic cross-fading for cinema-recording shutter supply reverses the polarity of the motor mekameras with an electromotive film drive and in the circuit of the camera motor and an exposure controller, the shutter S of which is a switching means that is defined by pressing a cross-fading button in the th point in time after the start of the film rewind the sense of a fade-out arbitrarily interrupts the flow of current to the camera motor.
closed position can be reached; at the end there are cinema cameras of the type of aperture feed described above a polarity reversal of the motor is known that an exposure controller, z. B. is effected in the form and in the circuit of the io of a Wheatstone bridge, have the entwe camera motor a switching means is arranged, which the lens aperture or the sector aperture at a defined point in time after the beginning according to the prevailing object brightness redes film return the current flow It is known to interrupt an electrical switch motor, marked thereby, by means of which the diaphragm servomotor (in the case of net, that a motor-controlled diaphragm for the definition of this point in time) or the measuring mechanism (in the case of a time generator known per se (13, 14; 35, 39; 41, diaphragm vanes operated directly by the measuring mechanism) un-42) is provided, which is automatically switched on when the polarity of the bypassing of the control circuit is reversed to the motor (7) and a power source can be connected. As a result of this, after the specified time has elapsed, the shutter is slowly closed completely, actuated medium. ao ie it is dimmed. 2. Automatic cross-fading according to claim 1, the fading and vice versa also the characterized in that as a time generator, a fade-in process is performed in a known manner on the scene mechanical Time generator (13, 14) is provided, nenende and at the beginning of the scene for film design which is used in a manner known per se when switching. But it is also known to use crossfader Direction of rotation of the camera motor (7) to work 35 fertilize, in which the end of the one ten begins and after a predetermined time scene, as it were, into the beginning of the next scene the circuit of the motor opens. runs into it. The individual to carry out 3. Automatic cross-fading according to claim 1, the method steps are: Fade down to fully characterized in that a constant closure of the shutter, switching of the electronic time generator (35, 39) is provided as a time generator, 30 running direction of the camera motor and return transport of the when the fade button is pressed ( 32 α) of the film to the point at which the dimming function was activated as a timer and began with Umpo-, and the film was run again with the motor (7) moving from timing to timing with the shutter slowly opening. which is switched over and with the means (35 to It is now already known, after the initiation of the 42) are provided, which ensure that the 35 glare process the film transport in the camera formed time equal to the previously measured time after a specified number of images or after a is and at the end of the formed time, the engine will automatically stop the specified time. Furthermore is (7) is shut down. it is known, after switching the film transport direction 4. Automatic cross-fading according to claim 3, processing and restarting the camera this backward characterized in that the electronic 40 transport of the film also automatically zubeen-Zeitbildner from a constant current source (35 to the. However, the known device (German 38) and a capacitor (39), the see patent specification 1 257 564) has the disadvantage that the probably in the time measurement as well as in the time frame inclusion of the limiting the return transport can be used that the capacitor time generator must be made manually and (39) Switching means (γ2Γ,; · 22 ') are available, the 45 that the switchover to return transport is not when reversing the polarity of the motor (7) are operated automatically, but manually with a special and also reverse the polarity of the capacitor (39), hand movement must be carried out. From other- and that a short-circuited in timing Ren proposals, although it is already known, the end transistor (41) is provided for the automation during the reversal phase of the shutter closing movement of the capacitor receives reverse voltage and 50 see switching of the film direction to reverse becomes conductive when using the capacitor voltage transport, however, a camera would be in becomes zero. which combines these two known measures 5. Automatic cross-fading according to the claims would still have the disadvantage that the Chen 3 and 4, characterized in that automatically limiting the film return transport Compensation of the base-emitter voltage of the 55 time generator in a special switching process turned on transistor (41) a diode (42) is provided, would have to be switched. whose voltage drop to the voltage at the con- The present invention is therefore the capacitor (39) is added and which would give the same basis to create a film camera in which Like the basic one, the user only has the current-voltage characteristic curve in the case of a dissolve Emitter path of the transistor (41). 60 has to press a dissolve button, whereupon the stopping down and the return transport of the the length of the film passed through the glare process as well as the The camera switches off automatically at the end of the film transport. The invention relates to a cross-fading device. According to the invention, this object is in a device for cinema recording cameras with electric motor cross-fading device of the type mentioned at the beginning Schem film drive and an exposure regulator, solved by the fact that to define this point in time sen aperture is provided by actuating a cross-fading tab a per se known time generator, the