KR0129824B1 - Camera having correcting function of main subject reflect rate - Google Patents

Abstract

A camera having object reflection rate correction function and its controlling method is provided to precisely present colors of an object to be taken and to obtain a photograph with appropriate exposure. The camera comprises a switch means including a first step release switch, a second step release switch, a photographing mode switch, and a main object setting switch; a distance measuring means; a brightness measuring means; a photographing control means for outputting a data representing kinds of a plurality of main objects having different reflection rates if the photographing mode switch is activated, and for reading out correction rate of exposure according to the kind of the object selected by the main object setting switch, and for setting an exposure rate based on the measured distance, brightness and correction rate of exposure if the first step release switch is activated, and for performing photographing operation by outputting a driving signal according to the prescribed exposure rate if the second step release switch is activated.

Description

Camera with main subject reflectivity correction function and its control method

1 is a state diagram showing a metering method of a general exposure meter,

2 is a state diagram showing a subject reproduction relationship with a subject condition and a reflected light exposure meter.

3 is a block diagram illustrating a configuration of a main subject reflectance correction according to an embodiment of the present invention.

4 is a detailed configuration diagram of an information display unit of a camera capable of correcting a main subject reflectance according to an embodiment of the present invention;

(A) and (b) of FIG. 5 are flowcharts of operations of a camera whose main subject reflectance can be corrected according to an embodiment of the present invention.

6 is a detailed block diagram of a photographing controller according to an exemplary embodiment of the present invention.

The present invention relates to a camera capable of subject subject reflectance correction and a control method thereof. More specifically, when a user sets a subject to be photographed and a contrast of the subject, the exposure amount is corrected according to the reflectance to obtain a photograph of an appropriate exposure. The present invention relates to a camera capable of correcting a main subject reflectance and a control method thereof.

In general, the camera's exposure meter is composed of a reflected light exposure meter and an incident light exposure meter. As shown in FIG. 1, the incident light exposure meter is a method of measuring light that illuminates a subject, and the reflected light exposure meter is a method of measuring light that is reflected by the subject at an actual photographing position and passed through a camera lens.

The reflective exposure meter is equipped with a photometric sensor inside the camera, the microcomputer detects the amount of current output according to the intensity of the light to be measured to set the appropriate exposure amount accordingly.

In addition, as a metering method for proper exposure control, a weighted average metering that focuses on the center of the screen, a spot metering that measures only a minute portion of the screen, and the screen is divided into several units to analyze and calculate the respective metering data. Multi-part measurement methods for determining exposure are used.

In the reflection type exposure meter as described above, the exposure of the subject is controlled based on a reference point of 18% reflectance. The 18% reflectivity represents an algebraic median value of 90% for the average white reflectivity and 3 to 4% for the black reflectance, and controls the exposure of the subject measured based on the 18% reflectance.

In other words, the reflective exposure meter determines that the reflectance is higher than the reference point of 18% for the white subject, and thus the exposure amount is adjusted to be closer to the reflectance of 18% because the reflectance is higher than the current average brightness. Underexposure occurs when the image is darker than white.

In addition, when photographing a black subject, since the reflectance is lower than the reference point of 18%, it is determined to be darker than the current average brightness, and the exposure is adjusted so that the reflectance is close to 18%. .

As shown in FIG. 2, the white or black subject is reproduced in a color close to gray as it passes through the exposure meter and is not reproduced in the original color according to the above-described reflectance adjustment.

In order to solve the above-mentioned overexposure and underexposure, the exposure compensation button is mounted so that a photographer can compulsorily correct the exposure to increase the exposure or decrease the exposure to correct the exposure to obtain an appropriate exposure. There is technology.

However, in the above-described conventional technique, since the photometric calculation according to exposure compensation is performed inside the microcomputer, only a photographer who has considerable experience can know how much correction is necessary to obtain a photograph with proper exposure. In the case of taking a picture, there is a disadvantage in that the picture is completely different from the intention of the photographer.

In addition, if the exposure compensation amount is set incorrectly, a picture that is not properly exposed is taken immediately, which causes a disadvantage of missing an important moment to be photographed.

Therefore, an object of the present invention is to solve the above-mentioned disadvantages, and presents a plurality of subjects having different reflectances to the photographer, and then reads the reflectance corresponding to the subject selected by the photographer to correct the exposure amount accordingly. Therefore, any photographer, including a beginner, can easily correct the reflectance of the main subject to be photographed, more accurately reproduce the color of the subject to be photographed, and have a main subject reflectance correction function to obtain a photograph of an appropriate exposure. It is to provide a camera and a control method thereof.

The configuration of the present invention to achieve the above object is composed of a release first stage switch, a release two stage switch, a shooting mode switch, the main subject setting switch, each switch outputs a plurality of electrical signals corresponding to the operating state Switch means for performing; Automatic ranging means for measuring a distance of an object and outputting an electrical signal corresponding thereto; Luminance metering means for measuring the luminance of the subject and outputting an electrical signal corresponding thereto; An input port for receiving a signal output from the auto-measuring means and a switch means, a bus for transmitting a plurality of signals and applied data through the input port, and a signal output from the luminance metering means as digital signals A signal converter which converts and outputs a signal on the bus, a plurality of signals output on the bus, a memory having a main subject type having a different reflectance and an exposure compensation amount, and a photographing mode via the bus When the signal corresponding to the switch operation is input, data for displaying the types of the main subjects having different reflectances are output on the bus, and the main subjects displayed via the bus input signals are displayed according to the signals of the main subject setting switch inputted through the bus. Set one of the types of subjects, and select the subject according to the main subject type set from the memory. After the correction amount is read, when a signal corresponding to the operation of the first release switch is input, the signal corresponding to the distance and luminance of the subject on the bus is received and photographed according to the measured subject distance and luminance and the exposure correction amount read. Calculates the exposure amount to perform the operation, stores it in the memory, and when a signal corresponding to the release two-stage switch is input, reads the stored exposure amount from the memory, and drives the driving signal for performing the imaging according to the exposure amount onto the bus. Photographing control means comprising a central processing unit for outputting and an output port for receiving and outputting driving signals and data on the bus; Information display means which is driven in accordance with the data output from the photographing control means and displays a plurality of types of main subjects having different reflectances; Aperture driving means which is operated according to a driving signal outputted from the photographing control means to control the exposure amount of the film; And shutter driving means which is operated according to the driving signal output from the photographing means to control the exposure time of the film.

Another aspect of the present invention for achieving the above object, the step of initializing all the operating circuit and the use parameters when the power is applied to the camera, and then determining whether the operation mode switch; Displaying a plurality of types of main subjects set to the photographer when the photographing mode switch is operated; Determining the type of the main subject set according to the operation of the subject setting switch, and reading an exposure compensation amount according to the average reflectance of the set main subject; Measuring the brightness of the subject by measuring a distance to the subject when the release first stage switch is operated; Calculating and setting an exposure amount according to the measured subject distance and luminance and the exposure compensation amount according to the type of the main subject set above; When the release two-stage switch is activated, the shutter is operated by operating the aperture and the shutter in accordance with the exposure amount set above, and then terminating.

When described with reference to the accompanying drawings the most preferred embodiment which can easily implement the present invention by the above configuration as follows.

3 is a block diagram of a camera capable of correcting a main subject reflectance according to an embodiment of the present invention, and FIG. 4 is a detailed block diagram of an information display unit of a camera capable of correcting a main subject reflectance according to an embodiment of the present invention. 5A and 5B are flowcharts illustrating operations of a main subject reflectance correction according to an exemplary embodiment of the present invention, and FIG. 6 is a detailed configuration diagram of a photographing controller according to an exemplary embodiment of the present invention.

As shown in FIG. 3, a configuration of a camera having a main subject reflectance correction function according to an embodiment of the present invention includes a release first stage switch S1, a release second stage switch S2, and a photographing mode switch. S3), the main subject setting switch S4, the main subject color setting switch S5, the automatic metering unit 20 for measuring the distance to the subject, the luminance meter 10 for measuring the subject luminance, And connected to the outputs of the switches S1 to S5, the automatic metering unit 20, and the luminance metering unit 10 to output data corresponding to the type and color of the main subject, and set the type, color, and subject of the main subject. The exposure control unit calculates the exposure amount according to the distance and the brightness, and outputs a corresponding control signal to perform a shooting operation according to the calculated exposure amount, and is connected to an output terminal of the shooting control unit 30 to provide a plurality of main subject types and Table for color data To the information display unit 40, the shutter driver 50 which is operated according to the control signal of the photographing control unit 30 to perform photographing, the aperture driver 60, and the film motor driver 70 to wind the film. Is done.

The configuration of the information display unit 40 according to the embodiment of the present invention is as shown in FIG. 4, but is not limited thereto.

As shown in FIG. 6, the configuration of the photographing control unit 30 according to the embodiment of the present invention includes a bus 33 which transmits the operation signals, ranging signals, metering signals, and control signals of the switches S1 to S5. And an A / D converter 31 for converting a signal applied to the output terminal of the luminance metering unit 10 into a digital signal and outputting the signal to the bus 33, the automatic measuring unit 10, and a plurality of switches. An input port 32 which receives a plurality of signals connected to the output terminals of S1 to S5 and outputs them onto the bus 33; and an A / D converter 31 connected to the bus 33; A CPU 34 for performing a process for correcting a main subject reflectance according to a plurality of signals input through the input port 32, that is, a plurality of data, and outputting a corresponding control signal onto the bus 33; Oscillation section 35 for outputting a clock signal for operation of the operation 34) and operation necessary for operation of the CPU 34; ROM 36 in which a program is stored, RAM 37 for storing a plurality of data on the bus 33, and an output port for outputting a control signal connected to and applied to the bus 33 to a corresponding device ( 38).

In the RAM 37 according to the exemplary embodiment of the present invention, a plurality of types of subjects and colors of stages having different reflectances, and exposure correction amounts corresponding to the types and colors are stored, respectively.

The operation of the camera having the main subject reflectance correction function according to the embodiment of the present invention by the above configuration is as follows.

According to the present invention, the condition of the main subject to be photographed is displayed on the information display unit 40 composed of the liquid crystal display element, the photographer sets the type of the main subject to be photographed with the operation lever and the switch, and the color yarn according to the set main subject is added. If set, the camera compensates the exposure amount according to the correction value according to the main subject type and color set above, in the operation of determining the exposure amount by the shutter speed and the aperture value for proper exposure during the automatic exposure control. Ensure proper exposure control.

According to the embodiment of the present invention, the color of the main subject that can be selected allows to select a color (contrast) from white to black where the reflectance changes, respectively.

When the camera power is applied, the oscillation unit 35 of the shooting control unit 30 operates to output a corresponding clock signal. According to the applied clock signal, the CPU 34 of the shooting control unit 30 captures the image by correcting the main subject reflectance correction. The routine for performing the operation is called from the ROM 36, and all the operation circuits and the use variables are initialized as shown in the attached Fig. 5 (S110), and then the shooting mode setting operation by the photographer in accordance with the applied signal. To judge.

In order to determine whether the photographing mode is set by the photographer, the photographing control 30 determines whether the photographing mode switch S3 is in operation (S120). When the photographing mode switch S3 is turned on, an electric signal corresponding to the photographing mode switch S3 is output on the bus 33 through the input port 32 of the photographing controller 30, and a control signal of the CPU 34 (on the bus Signal on the bus 33 is input to the CPU 34 according to the signal and the signal for inputting data).

When a signal corresponding to the operation of the shooting mode switch S3 is input, the CPU 34 of the capturing controller 30 receives a plurality of types of subjects having different reflectances, and the color of the subject (step-by-step color from white to black). ) Is read from the RAM 37 and output on the bus 33. The data output on the bus 33 is input to the information display unit 40 through the output port 38, and the information display unit 40 displays the input data as shown in FIG. .

The display state for setting the main subject and the color of the main subject of the information display unit 40 according to the embodiment of the present invention is as shown in FIG.

In FIG. 4, a is a display mode when the main subject to be photographed is a tree or a flower, and b is a display mode when the main subject to be photographed is a light emitting device such as a lamp, and c is a display mode when the subject is a human. Mode, d is the display mode when the main subject is in the background of the sky, e is the display mode when the main subject is a window with little reflectivity, f is the display mode when the car has a very high reflectance of the main subject, g Denotes a display mode when the main subject is snowy, and h corresponds to a display mode when the main subject is a building, and since the reflectance is different according to each main subject type, the corresponding exposure compensation amount is set differently. It is stored in the RAM 37 of 30).

In addition, i denotes the color of the subject to be photographed in a gradual level from black to white, and allows the photographer to set the color of the main subject to be photographed at each step.

As described above, when the shooting mode switch S3 is operated to display data corresponding to the types and colors of the plurality of subjects having different reflectances on the information display unit 40, the photographer operates the main subject setting switch S4. Select one of the multiple subject types displayed.

The CPU 34 of the capturing controller 30 outputs data corresponding to the type and color of the subject, and then displays a signal corresponding to the operation of the main subject setting switch S4 from the bus 33. One of a plurality of subject types is set (S140 to S150).

When the photographer sets the desired main subject, the CPU 34 of the photographing controller 30 displays the set mode, that is, the display mode corresponding to the selected subject flashes to indicate that the mode is set, or uses an arrow such as k of FIG. As a result, a control signal for indicating that the mode indicated by the arrow is set may be output. Accordingly, the above display operation is performed on the information display unit 40.

When the main subject to be photographed is set as described above, the exposure compensation amount corresponding to the set main subject is read from the RAM 37 (S160).

After reading the exposure compensation amount according to the main subject set above, the CPU 34 of the photographing controller 30 operates the main subject color setting switch S5 for selecting the color level of the main subject set from the bus 33. When a signal corresponding to the is applied, one color step among a plurality of displayed color steps is set, and an exposure compensation amount corresponding to the set color is read from the RAM 37 (S170 to S180).

For example, when the photographer selects the color of the main subject close to white with high reflectance, the CPU 34 reads the exposure compensation amount according to the reflectance corresponding to the selected color.

After reading the exposure compensation amount according to the type and color of the subject set by the photographer in order to obtain a picture of the appropriate exposure, the CPU 34 determines whether the signal of the release first stage switch S1 is input (S190).

When the photographer presses a release button (not shown) to photograph the set subject, the release first stage switch S1 is operated. When the release first stage switch S1 is operated, a corresponding signal is input to the CPU 34 through an input port 32, and the CPU 34 receives a signal corresponding to the release first stage switch S1 operation. The automatic distance measuring unit 20 is driven to measure the distance to the subject, and the luminance amount of the subject is measured according to the signal of the luminance metering unit 10 input through the A / D converter 31 (S200 to S). S210).

The automatic metering unit 20 and the luminance metering unit 10 respectively measure the distance of the subject and the amount of luminance of the subject, and output an electrical signal corresponding to the photographing controller 30.

In the above, the CPU 34 of the photographing controller 30 performs an exposure operation process according to the measured subject distance and luminance amount and the exposure compensation amount according to the set subject type and color, and according to the shutter speed and the aperture value. The exposure amount is calculated (S220).

After storing the calculated exposure amount in the RAM 37, the CPU 34 receives a signal corresponding to the operation of the release two-stage switch S2 from the bus 33 (S230), and then from the RAM 37. The exposure amount calculated above is read out, and a drive signal corresponding to the read exposure amount is output on the bus 33.

The drive signal output on the bus 33 is input to the shutter driver 50 and the aperture driver 60 through the output port 38, respectively, and the aperture driver 60 is a driver for applying an aperture (not shown). In response to the signal, the shutter driver 50 operates a shutter (not shown) according to an applied driving signal.

Therefore, the exposure amount corresponding to the exposure amount corresponding to the opening amount of the aperture is made on the film during the exposure time corresponding to the operation time of the shutter, and the desired subject is photographed (S240 to S250).

After photographing the subject to be photographed according to an appropriate exposure amount, the CPU 34 outputs a control signal for winding the photographed film onto the bus 33 and is applied through the output port 38. According to the control signal, the film motor driving unit 70 is driven to wind the film of one cut taken (S260 to S270).

As described above, in the embodiment of the present invention, when the plurality of subject types and colors having different reflectances are displayed to the photographer, the photographer simply sets the main subject to be photographed, and inputs the corresponding color level. By considering the standard reflectance of the condition set at the time of calculation and correcting the value at the time of exposure calculation, even a beginner can easily obtain an exposure close to the natural color of the subject to be photographed.

In addition, it is possible to provide a camera having a main subject reflectance correction function, which has an effect of more accurate exposure control by compensating for the defect that the output data of the reflection type exposure meter currently applied to the automatic single-lens lev camera depends on the reflectance of the subject. have.

Claims (7)

A switch means comprising a release first stage switch, a release second stage switch, a photographing mode switch, and a main subject setting switch, and outputting a plurality of electrical signals corresponding to an operating state of each switch; Automatic ranging means for measuring a distance of the subject and outputting an electrical signal corresponding thereto; Luminance metering means for measuring the luminance of the subject and outputting an electrical signal corresponding thereto; A digital signal may include an input port for receiving signals output from the auto-measuring means and a switch means, a bus for transmitting a plurality of signals and data applied through the input port, and a signal output from the luminance metering means. A signal converter which converts and outputs a signal on the bus, a plurality of signals output on the bus, a memory having a main subject type having a different reflectance and an exposure compensation amount, and a photographing mode via the bus When the signal corresponding to the switch operation is input, data for displaying the types of the main subjects having different reflectances are output on the bus, and the main subjects displayed via the bus input signals are displayed according to the signals of the main subject setting switch inputted through the bus. Set one of the types of subjects, and select the subject according to the main subject type set from the memory. After the correction amount is read, when a signal corresponding to the operation of the first release switch is input, the signal corresponding to the distance and luminance of the subject on the bus is received and photographed according to the measured subject distance and luminance and the exposure correction amount read. Calculates the exposure amount to perform the operation and stores it in the memory, and when a signal corresponding to the release two-stage switch is input, the stored exposure amount is read from the memory, and a driving signal for photographing according to the exposure amount is output on the bus. Photographing control means comprising a central processing unit and an output port for receiving and outputting driving signals and data on the bus; Information display means which is driven in accordance with the data output from the photographing control means and displays a plurality of types of main subjects having different reflectances; Aperture driving means which is operated according to a driving signal outputted from the photographing control means to control the exposure amount of the film; And a shutter driving means which is operated according to a driving signal output from the photographing control means to control the exposure time of the film. The method according to claim 1, wherein the switch means further comprises a main subject color setting switch for selecting a color of a subject to be photographed by a photographer from white to black, each having a different reflectance. And a switch connected to the input port of the photographing control means. The memory of claim 2, wherein the memory of the photographing control means further includes and stores each color and a corresponding exposure compensation amount according to the type of the main subject having different reflectances, and the central processing unit of the photographing control means controls the bus. When the signal according to the operation of the shooting mode switch is input, the corresponding data is output on the bus so that the color of the subject is displayed step by step from white to black, and when the signal according to the operation of the main subject color setting switch is applied, the color of the subject To calculate the exposure amount according to the subject distance, brightness, exposure compensation amount according to the main subject type, and exposure compensation amount corresponding to the color inputted through the bus by reading the exposure compensation amount corresponding to the set color of the main subject from the memory. Camera with main subject reflectivity correction function characterized by. Switch means comprising a photographing mode switch, a main subject setting switch, a main subject color setting switch, and outputting a plurality of electrical signals corresponding to an operation state of each switch; A memory for transmitting the signal output from the switch means and the applied data, and a plurality of signals output on the bus, each of which has a main subject type having different reflectances, a step color, and a corresponding exposure compensation amount And a central processing unit for outputting data on the bus to display the types and color of the plurality of main subjects having different reflectances, respectively, when a signal corresponding to the photographing mode switch operation is input through the bus. Control means including an input port for receiving an input; And information display means which is driven according to the data output from the control means and displays the types and color of the plurality of main subjects having different reflectances, respectively. Initializing all operation circuits and use parameters when power is supplied to the camera, and then determining whether the photographing mode switch is operated; Displaying a plurality of types of main subjects set to the photographer when the photographing mode switch is operated; Determining the type of the main subject set according to the operation of the subject setting switch, and reading an exposure compensation amount according to the average reflectance of the set main subject; Measuring the brightness of the subject by measuring a distance to the subject when the release first stage switch is operated; Calculating and setting an exposure amount according to the measured subject distance and luminance and the exposure compensation amount according to the type of the main subject set above; When the release two-stage switch is operated, the control method of the camera having a main subject reflectivity correction function, characterized in that it comprises the step of performing the shooting by operating the aperture and the shutter according to the exposure amount set above. The photographing apparatus of claim 5, wherein when the photographing mode switch is operated, data for setting the colors of the subjects having different reflectances for each step are displayed through information display means, and then the subject color setting switch is operated to photograph the subject. When the color is set, the main subject, characterized in that by reading the exposure compensation amount according to the reflectance of the set color, the exposure amount is calculated by adjusting the exposure amount according to the exposure compensation according to the color when calculating the exposure amount Control method of a camera having a reflectance correction function. The method according to claim 5, wherein the color level of the subject is in steps from black to white having different reflectances, respectively.