SU1163307A1 - Device for monitoring image stability in cine camera - Google Patents

Abstract

1. DEVICE FOR MONITORING THE STABILITY OF THE IMAGE IN THE CINEMA, containing the case, the optical system in the form of successively installed illuminators with a deflector, a lens, a reflector located behind the film channel, as well as photo cells located in the image of the perforation hole formed in the reverse direction of the beams of the perforation hole on its edges and associated with a recording instrument. characterized in that, in order to increase accuracy by taking into account the vibrations of the cinema camera body, it is equipped with a vibration sensor, made in the form of an opaque plate mounted on the body, installed in the image plane of the lens formed in the reverse direction of the beam with the possibility of blocking part of the luminous flux, and an additional lens and photocell In this case, the plane of location of the photocell is aligned with the image plane of the additional lens, and the additional photocell is located in the central part per minute image foratsionnogo apertures and bonded to re.-; device and one of the inputs of the entered adder, the other input of which is connected to the photocells, and the output is connected with a recording device. Mr. Phie1

Description

2, the device according to claim 1, that is, that the deflector is made in the form of a mirror installed with the possibility of crossing one ton of the light flux and located between the main lens and the opaque plate.

The invention relates to film equipment, namely, devices for controlling image stability in cinema cameras, for example, in film projectors, film copying equipment and nightclubs. A device is known for determining the stability of a film frame, which contains a light source, a lens and a photodetector for registering a modulated light, reflected from a mirror, P. In order to determine the magnitude of image stability using the known device 3, the test camera should be charged with a test film with gaps made with high accuracy. The closest in technical essence to the invention is a device for controlling the operation of a hopping mechanism in a cinema camera, containing a light source with a deflector in the form of a prism with a diaphragm, a lens, a reflector located behind a film strip, and photo cells for detecting changes in the values of the light fluxes incident on them, caused by sequentially displayed perforations and uneven rotation of the obturator, and a recording device. The light flux from the source of light passes through a prism with a diaphragm at the output end and a lens that directs a parallel beam to successively perforated perforations of the film, with a reflector located behind the plane. The reflected part of the light beam in the opposite direction passes through the same lens, which builds an enlarged image of successively changing perforations of the film in the plane of two photocells. Another part of the luminous flux reflected by the reflector is directed to the third photocell optically conjugated with it by the frequency of the signal on which the uniformity of rotation of the shutter is judged. When the camera operates, the position of the borders of the sequentially depicted perforations of the film is changed, which causes modulation of the light flux in amplitude in the first two photocells. Measuring the difference in the amplitudes of the output signals taken from these two photocells using a recording instrument determines the accuracy of the tested hopping mechanism or the magnitude of image stability in the horizontal and vertical directions 2j. The known device makes it possible to estimate the accuracy of the hopping mechanism of the camera while transporting the film and the uniformity of rotation of the obturator, but does not allow simultaneously assessing the magnitude of vibrations of the housing kk: the appliance as a whole and the vibrations of the film channel due to the inaccuracy of production , wear and unbalance of parts of the drive and tape drive mechanism of the camera, in particular the jump mechanism. The decrease in the accuracy of control in the device is due to the significant effect on the measurement results of changes in the magnitude of the useful luminous flux during registration, the faults in the production of the film, as well as changes in the reflectivity of different parts of the film roll. The purpose of the invention is to improve the accuracy of image stability control in a movie camera. This goal is achieved by the fact that a device for controlling image stability in a video camera contains a body, an optical system in the form of successively installed illuminators with a deflector, a lens, a reflector located behind the film channel, and photo cells located in the image in the back 1 During the course of the rays of the plane of the image of the perforation on its borders and connected with the registering device, it is equipped with a vibration sensor made in the form of an opaque plate mounted on the body, the plane of the image of the lens formed in the reverse direction of the ray with the possibility of overlapping part of the luminous flux and the additional lens and photoelectric element of this photoelectric plane is aligned with the image plane of the additional lens, and the additional photocell is located in the center of the perforation hole and is connected with the recording device and with one of the inputs of the input adder, the other input of which is connected to the photocells, and the output is connected with the recording device ohm In addition, the deflector is made in the form of a mirror installed with the possibility of blocking a part of the luminous flux and located between the main lens and a flat, non-transparent plate. Fig. 1 is a schematic diagram of an apparatus for monitoring image stability in a movie camera; Fig. 2 shows the plane of the image of the perforation hole of the filmstrip and the image of the opaque plate and the photocells located on it; FIG. 3 shows the block diagram of the information processing device; in fig. 4 and 5 - picture stability registers S of the film camera representing the sum of the inaccuracies of moving the film in the film channel and the vibration of the body of the device under study, the support of which is not connected with the image stability control device in the horizontal and vertical directions, respectively; in fig. 6 and 7 - register the vibrations of the casing of the camera body in the horizontal and vertical directions, respectively; Figures 8 and 9 are diagrams of inaccuracies of movement of a film in the film channel of the device under study, obtained by subtracting the registrams shown in Figures 4-6 and 5-7, respectively, in the horizontal and vertical directions; Figures 10 and II are graphs of image stability ranges in horizontal capra. Surface for synchronous and asynchronous types of cine-cameras, respectively} in FIG. 12 and 13 are graphs of the vibration ranges of the enclosures in the horizontal direction for. synchronous and asynchronous film cameras, respectively, in Fig. 14 and I5 are graphs of ranges of inaccuracies of moving in the horizontal direction of a film in movie channels of motion-picture apparatuses of the synchronous and, accordingly, asynchronous types. The device contains a source of light 1 of a projection action, a deflector 2, a front lens 3, a film channel 4 with a technological opening 5 specially made in it, through which a perforation opening 6 of a film strip 7 is visible, and a reflector 8. In one of the optically conjugate planes vibration sensor 9. For convenience of operation, an additional lens 10 is inserted into the device, which builds the image of the perforation hole 6 and the image of the vibration sensor 9 in the plane 11 of the location of the photo cells 12 - .17. Current signals of photocells 12 17 are fed to the input of the amplifier. 18, conjugated with a source of 19 pit anis. The outputs of the amplifier 18 are also connected to the input of the registering device 20 through the adder 21. The light beam emitted by the illuminator 1 is reflected from a deflector, for example, a flat mirror 2, with the help of the main lens 3 being concentrated through the technological one. hole 5 in the film channel 4 in the plane of the perforation hole 6 of the film 7, behind which the reflector 8 is located. The main lens 3 builds in the reverse direction of the rays an image of the illuminated perforation hole 6 in the plane of the vibration sensor 9, optically conjugated with the help of an additional lens 10 with the plane 11 the locations of the photocells 12-17, while the photocells 13 and 15 are additional photocells located No. 1 on the previously free from the main photocells 14 and 15 of the vertical and horizontal borders of the images voltage and perforations 6 {2). Moreover, photoelectric cells 12, 13 and 14, 15, located on opposite edges of the image and the perforation hole 6, are connected in pairs according to the current signal subtraction circuit.

Due to the difference. . current signals from photocells 12, 13 and 14, 15 connected in pairs and located respectively on opposite vertical and horizontal faces. 20 of the image of the perforation 6 supplied to the input of the amplifier 18, the accuracy of operation of the device is achieved, since the effect of most no-t 25 mech is excluded. .

Current signals are also input to the amplifier 18 from the photocell 16, which follows the uniform rotation of the obturator and the photocell 17, which is optically coupled to the vibration sensor 9.

Optical design of the device; (FIG) is designed in such a way that the luminous flux reflected from the reflector 8 placed behind the controlled perforations 6 during the standing of the film 7 illuminates all the photocells 12 17 simultaneously.

. The modulation of the light fluxes falling on the photocells 12-15 is caused by the displacements of the controlled perforations of the transported film 7, and the modulation on the photocell 17 is caused by the vibrations of the vibrating sensor 9 mounted on the casing of the camera.

The images of the controlled perforations 6 and the vibration sensor 9 are built in the plane of the position of the photo cells 12-17.

This device allows you to simultaneously receive current signals characterizing the vibration of the body (not shown) of the camera, 55 as well as the current signal, due to the sum of image stability and vibration of the camera body during the standing phase of the film 7 in the movie channel 4 of the camera. At this point in time, the device operates as follows. The light beam emitted by the illuminator 1, reflected from the deflector 2, such as a flat mirror, is concentrated using the primary lens 3 through the technological opening 5 in the film channel 4 in the plane of the perforation hole 6 of the film strip 7, behind which the reflector 8 is located. the reverse path of the rays, the image q of the illuminated perforation hole 6 in the plane of the vibration sensor 9, optically conjugated by an additional lens 10 to the plane of the photocell 12 to 17, from which the signal You are fed to amplifiers 18, and then a portion of the amplified signals are fed directly to the input of the recording device 20. A portion of the amplified signal from a pair of photocell 14 and 5 connected by the subtraction circuit, which controls the image stability in the horizontal direction, and a portion of the amplified signal Photocell 17, which controls the vibration of the casing of the camera in the horizontal direction, enters the adder 21, after which the recording device 20 registers the in resistance value pixels in the horizontal direction. At the same time, in the horizontal direction, on the registration device 20, for example a 6-track recorder of the type H338, a total registogram of image stability and vibration of the housing of the apparatus, as well as a registry of vibration of the body of the camera is recorded. The registograms for the vertical direction can be simultaneously recorded in the same way.

Registograms (Figures 4-7) - a graphic record of image stability in a movie camera is a complex cyclic-1

II process with a period of T - t-,

24

representing the sum of the oscillations of the apparatus and the inaccuracy of movement of the 8th film from frame to frame in the film channel of the camera in vertical and horizontal directions .. On all registrogrammes, the cyclic T 27 s period consists of two almost equal parts: A - corresponds to the phase of standing ( the lack of transport in the intermittent motion of the film, when the shutter of the movie camera does not prevent the passage of the light beam illuminating with the help of the stability control device, the B - phase of motion films in the film channel per frame step when the useful luminous flux of the image stability control device is blocked by the device's tutor. Thus, the useful information about image stability in the kino-apparat is contained in section A (each period. The proposed device allows you to simultaneously receive four Registrams (Fig.4 - 7), which is significant when recording cyclic processes, in which from period to period there is no complete repeatability of 1,078 magnitudes and forms of monitored parameters. The graphs characterizing the results of statistical processing of the measurements obtained using this device (see Fig. 10-15) show the ranges of the measured parameters, limited respectively by the minimum solid and maximum by the dotted lines. Moreover, the graphics of vibrations of the casing of the camera are given for different types of supports. Thus, the use of the proposed device, which makes it possible to simultaneously measure the magnitude of image stability and the vibration of the body of all types of movie cameras in the end-to-end cinematographic process, makes it possible to significantly improve the measurement accuracy and promptly make recommendations for improving the quality of the films produced, i.e. to differentiate such factors as deviation of the state of the film from the standard, wear and tear or imbalance of the transport mechanism of the camera, condition and quality of the support on which this apparatus is fixed, etc.

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Claims (2)

1. DEVICE FOR CONTROL • THE ROLE OF STABILITY OF THE IMAGE IN THE FILM APPARATUS, comprising a housing, an optical system in the form of sequentially mounted illuminator with a deflector, a lens, a reflector located behind the film channel, and photocells located in the image plane of the perforation hole formed in the reverse direction of the rays at its borders and characterized in that, in order to improve accuracy by taking into account vibrations of the cinema camera body, it is equipped with a vibration sensor made in the form of a fixed a pupil plate installed in the reverse image plane of the lens image with the possibility of blocking part of the light flux, and an additional lens and photocell, while the plane of location of the photocells is aligned with the image plane of the additional lens, and the additional photocell is located in the central part of the image of the perforation hole and connected to the recording device and to one of the inputs of the entered adder, the other input of which is connected to the photocells, and the output with knitted with register- 2. The device according to claim 1, with the exception of the fact that the part of the light is blocked off by the fact that the deflector is made and located between the main form of a mirror mounted by a prospective lens and an opaque plate.