JP2552724B2 - Photo printing method - Google Patents

Description

The present invention relates to a photographic printing method, and more particularly to a photographic printing method for determining a printing exposure amount using data representing a photographing state.

[Conventional technology]

In photographic printing, the average transmission density of the frames recorded on the photographic film is measured, and the printing exposure amount is calculated according to this average transmission density. This exposure control is called the LATD method, and it is possible to finish a printed photograph with proper density and color balance for about 70% of the photographic film for which printing was requested. In recent years, in order to increase the proportion of properly printed photographs, many have attached a scanner that measures each point on the screen. In this photo printer with a scanner, the maximum transmission density, the minimum transmission density, and the average transmission density in each area that virtually divides the screen are obtained by using the transmission density of each point on the screen, and these are used as the characteristic values. , The exposure amount of printing by LATD method is corrected.

[Problems to be Solved by the Invention]

The above-described conventional photographic printing method finds the characteristics of the scene of the frame to be printed and corrects the exposure amount for printing, and it is possible to increase the proportion of the frame that is finished to an appropriate density. However, there are two types of scenes that cannot be identified by photometry with a scanner, but need to reverse the increase / decrease in the amount of printing exposure, or increase / decrease only one of them.

For example, a nighttime flash photography scene and an underexposed scene have a common point in that both have a low average transmission density, and a different point is whether or not a portion having a high transmission density is a main part. However, since it is difficult for the scanner to find the main part, it is impossible to determine the proper printing exposure amount for these two types of scenes.

In addition, the background is common in both the backlit scene and the scene in which the main subject with a bright background (white wall, fusuma, etc.) is flash shot or in the daylight sync, and the difference is the background. And the density difference between the main subject and the main subject. In these two types of scenes as well, the main subject cannot be identified, and therefore the appropriate printing exposure amount cannot be determined for both.

It is an object of the present invention to provide a photographic printing method capable of determining an appropriate printing exposure amount according to the characteristics of a scene.

[Means for solving the problem]

In order to achieve the above object, the present invention records strobe light emission data and subject brightness data at the time of taking a photograph, reads these data at the time of printing a photograph, and classifies scenes of frames according to the presence or absence of strobe photography and the subject brightness. Done,
The printing exposure amount calculation method such as the calculation expression prepared for each scene is selected to calculate the printing exposure amount of the frame.

In another invention, strobe light emission data and subject distance data are used in addition to strobe light emission data and subject brightness data. Furthermore, another invention uses strobe emission data, subject brightness data, and subject distance data,
The scenes are further classified, and the optimum printing exposure amount is determined according to the characteristics of each scene.

[Action]

In the present invention, the stroboscopic light emission data recorded at the time of photographing is used, so that the stroboscopic photographing scene and a scene similar thereto can be surely discriminated, and the optimum printing exposure amount for each scene can be determined. In addition, since the subject brightness data recorded at the time of shooting is used, it is possible to distinguish between a low brightness strobe shooting scene and a daytime synchronized shooting scene. Furthermore, by using the subject distance data, a night view shooting scene, nighttime or indoor shooting It is possible to identify the scene and the close-up scene and determine the printing exposure amount for finishing each of these scenes to an appropriate density.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a camera for recording shooting condition data. A shutter mechanism 11 is disposed behind a taking lens 10 attached to a camera body (not shown). The shutter mechanism 11 includes, for example, two shutter blades.
The shutter blades 12 and 13 are provided with notches 12a and 13a, respectively. When the drive mechanism 14 moves the movable pin 15 toward the fixed pin 16, the shutter blades 12 and 13 move in a direction away from the fixed pin 16 and overlap the notches 12a and 13a. A portion where the notches 12a and 13a overlap is opened, and light passing through the portion enters the photographic film 17.

The photometric unit 22 is composed of a lens 20 and a light receiving element 21, and measures the subject brightness (BV) when a release button (not shown) is half pressed. The subject luminance signal output from the light receiving element 21 is sent to the exposure control circuit 23. The exposure control circuit 23 calculates a light value (LV) based on the subject luminance and the film sensitivity, and program-controls the shutter mechanism 11 via the drive mechanism 14. Also, since this light value is proportional to the subject brightness if the film sensitivity is the same,
In this embodiment, the light value is used as subject brightness data, and this is sent to the shooting condition data generation circuit 24.

The distance measuring sensor unit 26 includes a light receiving unit including a lens 27 and a line sensor 28, and a light projecting unit including a lens 29 and a light source 30. At the time of distance measurement when the release button is half-pressed, spot-like near-infrared light is projected from the light projecting portion toward the main subject, and the light reflected here enters the line sensor 28. The output signal of the line sensor 28 is sent to the distance measuring circuit 31, and the distance from the camera to the main subject is detected by examining where the reflected light is incident on the line sensor 28. The signal of the subject distance is sent to the lens setting mechanism 32, and when the release button is completely pressed, the photographing lens 10 is set at a position corresponding to the subject distance.

The subject distance signal from the distance measuring circuit 31 is sent to the photographing condition data generating circuit 24. Further, the photographing condition data generation circuit 24 receives the camera posture signal detected by the camera posture detection device 35 and the strobe light emission signal output from the strobe device 36. The photographing condition data generation circuit 24 drives the barcode recording device 38 via the driver 37 to record the photographing condition data represented by the barcode on the photographic film 17. In this embodiment, the barcode recording device 38 includes a liquid crystal display 39 for displaying a barcode.
And a flash discharge tube 40 that illuminates the same, and at the same time as or before or after the shooting of the subject, between the screen 17a and the film edge, strobe light emission data, subject brightness data, subject distance data, camera attitude data. , Imprint frame number data, etc.

As is well known, the strobe device 36 includes a subject brightness determination circuit, and when the subject has low brightness, the shutter mechanism 11
Flashes automatically in synchronization with. Further, when the daytime synchro switch is provided and turned on, the strobe device 36 emits light even if the subject has high brightness.

FIG. 2 shows a camera posture detection device. Two glass tubes 45 and 46 are arranged in a V shape in the vertical direction of the camera body, that is, along a plane parallel to the photographic film 17. On both ends of these glass tubes 45,46, contact pairs 47,48,4
9,50 installed, and each contact pair 47-50 turned ON
Mercury 51, 52 for enforcing the state is enclosed.

When the camera is in the horizontal position, the contact pairs 47 and 49 are turned on as shown in FIG. 2, and when the right hand holding the camera body is in the vertical position, the contact pairs 47 and 50 are connected. Turn on. In the vertical position with the left hand on top, contact pairs 48 and 49
Turn on. These contact pairs 47 to 50 are connected to the encoder 53, and converted into a signal representing the camera posture here and then sent to the photographing condition data generation circuit 24.

FIG. 3 shows a photographic film in which photographing condition data is recorded. Perforations 17b are perforated at regular intervals in the photo film 17, and one frame is fed by detecting the perforations 17b by a sensor of a winding stop device. Perforation 17b
On the opposite side of the, flash light emission data represented by a bar code
55, subject brightness data 56, subject distance data 57, camera posture data 58, and frame number data 59 are imprinted.
These photographing condition data are converted into a visible image by photo development. As described above, it is desirable to have an area for recording the photographing condition data in addition to the perforation 17b and have a photographic film structure capable of recording a plurality of data.

FIG. 4 shows a photographic printer. The white light emitted from the light source 62 passes through the cyan filter 63, the magenta filter 64, and the yellow filter 65, and then enters the mixing box 66. In these color correction filters 63 to 65, the amount of insertion into the optical path 68 is adjusted by the filter adjustment unit 67,
Thereby, the three-color light components of the printing light and the intensity thereof are adjusted. The mixing box 66 is one in which diffuser plates are attached to both ends of a rectangular tube that serves as an inner mirror surface.

The film carrier 70 is arranged at the print position, and the developed photographic film 17 is set and illuminated with the light transmitted through the mixing box 66. In order to ensure the flatness of the photo film 17, a film mask 71 is provided above the print position. This film mask
As is well known, the opening 71 is formed corresponding to the size of the frame, and when the photo film 17 is transferred, it is lifted up by a solenoid (not shown) and presses the photo film 17 during printing.

A bar code reader 72 is arranged in front of the print position, and the shooting condition data recorded in each frame is read when the bar code reader 72 is sent to the print position. The read shooting condition data is sent to the decoder 73 for decoding, the camera posture data is sent to the feature value extraction unit 78, and the remaining shooting condition data is sent to the scene classification unit 74.

A scanner 77 including a lens 75 and an image area sensor 76 is disposed obliquely above the print position, and measures the transmitted light of each point of the frame set at the print position. The signal of the scanner 77 is sent to the characteristic value extraction unit 78, and the average transmission density, the average transmission density of a specific area of the screen, etc. are calculated for each color. As shown in FIG. 5 to FIG. 6, the average transmission density of this specific area is as follows: average transmission density Dc at the center of the screen, average transmission density Df at the periphery of the screen, average transmission density Du at the top half of the screen, screen The average transmission density Dl of the lower half, the average transmission density Dri of the right half of the screen, and the average transmission density Dlf of the left half of the screen are used. Each of these areas is specified from the camera posture data read from the photo film 17. It should be noted that FIGS. 5 to 7 show the case where the camera posture is in the lateral position.

The scene classification unit 74 uses the shooting condition data and the average density of the specific area to determine the frames to be printed, for example, night scene shooting scenes, nighttime or indoor shooting scenes, close-up shooting scenes, daytime synchronized shooting scenes, and underexposure. The shooting scenes, backlight shooting scenes, and other shooting scenes are classified. Based on the characteristic value output from the characteristic value extraction unit 78 and the scene classification result determined by the scene classification unit 74, the printing exposure amount calculation unit 79 executes, for example, the following printing exposure amount calculation formula to calculate the printing exposure amount E. _i (i represents any one of red, green, and blue) is calculated, and this is sent to the controller 80.

E _i = K1j _i (DN _i −D _i ) ＋ K2j _i ＋ K3j _i Dmx _i ＋ K4j _i Dmi _i ＋ K5j _i (Dc _i −Df _i ) ＋ K6j _i (Dl _i −Du _i ) ＋ K7j _i (Dlf _i −Dri _i ) ・-(1) Here, each symbol is as follows.

Kj1 to Kj7: Constant j: Coefficient determined for each scene classification DN: Average transmission density of the control negative D: Average transmission density of the frame to be printed Dmx: Maximum transmission density Dmi: Minimum transmission density Formula of the above-mentioned printing exposure amount Since the constant is changed depending on the scene classification, the optimum printing exposure amount E _i can be determined according to the characteristics of the scene. However, there may be scenes in which the printing exposure dose calculation formula does not result in an appropriate density.
For such a scene, it is preferable to operate the keyboard and add / subtract the manual correction amount as is well known at the time of reheating.

Further, as another method, according to the scene classification result determined by the scene classification unit 74, the method of extracting the characteristic value of the characteristic value extraction unit 78 is changed, and further, the printing exposure amount calculation unit 79 calculates the expression according to the scene ( An arithmetic processing method different from 1) (for example, having a standard pattern depending on the scene, changing the exposure amount according to the degree of matching with it, or using an arithmetic expression using the skin color density depending on the scene) You may use.

A printing lens 83 is arranged above the print position, and the image of the set frame is enlarged and projected onto the color paper 85 arranged behind the paper mask 84. A shutter 87 whose opening and closing is controlled by a shutter driving unit 86 is arranged between the printing lens 83 and the color paper 85.

Next, the operation of the above embodiment will be described. When taking a picture, the camera is aimed at the main subject and the composition is determined. The camera posture at the time of determining the composition is detected by the camera posture detection device 35, coded by the encoder 53, and then sent to the photographing condition data generation circuit 24.

When the release button is pressed halfway, distance measurement and photometry of the main subject are started. During this distance measurement, the near-infrared light emitted from the light source 30 is converted into spot light by the lens 29, and this spot light is projected toward the main subject. The near-infrared light reflected by the main subject enters the line sensor 28 through the lens 27. The output signal of the line sensor 28 is sent to the distance measuring circuit 31, where the incident position of near infrared light is detected, and the subject distance is detected from this incident position.

On the other hand, the shooting scene including the main subject is metered by the photometry unit 22, a signal corresponding to the subject brightness is output from the light receiving element and sent to the exposure control circuit 23, and is calculated as the film sensitivity to calculate the light value (LV). To be done.

When the release button is completely pushed in, the lens setting mechanism 32 operates to move the taking lens 10 according to the subject distance detected by the distance measuring circuit 31. After the lens is set, the drive mechanism 14 reciprocates the drive pin 15 so that the notches 12a and 13a of the shutter blades 12 and 13 overlap each other. The amount of movement of the drive pin 15 is determined according to the light value calculated by the exposure control circuit 23. As a result, the shutter mechanism 11 program-controls the aperture size and the aperture time according to the light value, and displays the image of the subject on the photographic film 17. It should be noted that the shutter mechanism 11 is used when the subject has low brightness or during daytime synchronized photography.
The strobe device 36 emits light in synchronization with, and illuminates the subject.

Simultaneously with or before or after taking a photograph, the photographing condition data generating circuit 24 converts the camera posture, the presence / absence of stroboscopic light emission, the subject distance, and the light value into a bar code, and sends the bar code to the driver 37. The driver 37 drives the barcode recording device 38, and first displays the photographing condition data on the liquid crystal display 39. When this display becomes stable, the flash discharge tube 40 is caused to emit light, and various shooting condition data are displayed on the screen 17 as shown in FIG.
Imprint it around a.

When the filming of one photo film 17 is completed, the photo film 17 is taken out from the camera and submitted to the photo lab. At the photo developing station, the photo film 17 is developed to convert each frame recorded as a latent image and the photographing condition data recorded for each frame into a visible image.

The developed photo film 17 is loaded into the photo film carrier 70 of the photo printer shown in FIG. 4, and a frame to be printed, for example, 17a is set at the print position. Immediately before the frame 17a is transported to the print position, the barcode reader 72 reads the barcodes 55 to 59 of the photographing condition recorded on the peripheral portion of the frame 17a. The read barcodes 55 to 59 are decoded by the decoder 73, and then the flash emission data 55, the subject brightness data 56, and the subject distance data 57 are sent to the scene classification unit 74. Further, the camera posture data 58 has a feature value extraction unit 78 for determining the specific area.
Sent to

When the top 17a is set to the print position, the scanner 77 measures red, green, and blue transmitted light at each point on the top 17a. The photometric values of the three colors are sent to the characteristic value calculating unit 78, where the density is converted and temporarily stored in the memory. After this storage, the transmission density of each point is read out, and the maximum transmission density Dmx _i and the minimum transmission density Dmi _i are extracted. Further, the average transmission density D _{i of the} entire screen is calculated by obtaining the average value of the transmission density at each point. Further, the area is determined based on the camera posture data 58, and the average transmission density of each area is calculated. These characteristic values are sent to the printing exposure amount calculation section 79, and the average transmission density of the specific area is sent to the scene classification section 74.

As shown in FIG. 8, the scene classification unit 74 first determines in step 90 from the flash emission data 55 whether the frame 17a is a flash shooting scene. If frame 17
Is determined to be a flash photography scene, it is determined in step 91 from the subject brightness data 56 whether the light value (LV) is “4” or less. If it is determined that the scene has a light value of "4" or less, it is determined in step 92 whether the subject distance L is 10 m or more. When the subject distance L is 10 m or more, the frame 17a is a long-distance, low-luminance, stroboscopic image, and thus is determined to be a night-scene shooting scene.

If step 92 determines NO, then step
At 93, it is determined whether the subject distance L is 1 m or more. If "YES" is determined in this step 93,
The top 17a is determined to be a nighttime or indoor shooting scene.
If “NO” is determined in step 93, it is determined that the close-up shooting scene is set because the close-up / low-luminance / strobe shooting is performed.

If step 91 determines NO, then step
At 94, it is determined whether the subject distance L is 10 m or less. If "YES" is determined in this step 94,
It is determined that frame 17a is a daytime synchronized shooting scene,
When it is determined to be "NO", it is determined to be another shooting scene.

If step 90 returns NO, step
At 95 it is determined if the background is bright. This determination is made by comparing the average transmission density Dc in the central portion of the screen shown in FIG. 5 with the average transmission density Df in the peripheral portion of the screen. When it is determined to be "YES" in this step 95, it is determined that the frame 17a is a backlight shooting scene.

If NO at step 95, go to step
At 96, it is determined whether the exposure is underexposed. This determination can be performed by checking whether the average transmission density D _{i of the} entire screen is higher than a predetermined density. If "YES", it is determined that the frame 17a is an underexposure shooting scene, and if "NO", it is determined that it is another shooting scene.

The printing exposure amount calculation unit 79 determines the constants Kj1 to Kj7 based on the scene classification determined by the scene classification unit 74. This constant Kj
The printing exposure amount E _i is calculated by substituting the feature value calculated by the feature value extraction unit 78 into the printing exposure amount calculation formula (1) having 1 to Kj7, and this is sent to the controller 80.

After calculating the printing exposure amount E _i , the controller 80 adjusts the insertion amount of the color correction filters 63 to 65 into the optical path 68 according to the printing exposure amount E _i . After this filter adjustment, the shutter 87 is opened for a fixed time, and the frame 17a is printed and exposed on the color paper 85. In the same manner, each frame is sequentially photoprinted.

FIG. 9 shows another embodiment of scene classification,
In this embodiment, the object distance data is omitted to simplify the scene classification. Therefore, in this embodiment, it is classified into nighttime or indoor shooting scenes, daytime synchronized shooting scenes, retrograde shooting scenes, underexposed scenes, and other scenes.

In the scene classification of FIG. 10, only the subject brightness data is used to classify into four types of night scenes, indoor scenes, and daytime synchronized scenes.

In the above, the example in which the information indicating the shooting state is recorded on the film by the barcode is used, but the recording method is not limited to this. For example, a mark may be recorded at a predetermined position on the film by using a light emitting diode, and the information may be identified based on the presence or absence of this mark. Further, instead of recording on the film, it may be recorded on another recording medium such as an IC card or a cartridge, or may be a recording medium connected to the film.

In the above-described embodiment, the photographing condition data is recorded on the photo film, but the present invention can be applied to an electronic still camera. With this electronic still camera,
The photographing condition data is written in the magnetic floppy together with the image data. Then, when an image is displayed on the CRT and the image is printed on a color paper, the shooting condition data of this image is read and used for controlling the exposure amount for printing. When manually setting the taking lens, a sensor that changes the position of the taking lens or the lens driving member into an electric signal is used. Further, a distance zone may be used instead of the shooting distance itself.

〔The invention's effect〕

According to the present invention having the above-mentioned configuration, the shooting conditions are recorded at the time of taking a photograph, and the scenes are classified according to the shooting conditions at the time of printing the photograph. Therefore, it is possible to perform an appropriate scene classification and thereby perform highly accurate exposure control. .

Particularly, by using the flash emission data and the subject brightness data, it is possible to distinguish between a low brightness flash shooting scene and a daytime synchronized shooting scene. Further, by using the flash light emission data and the subject distance data, it is possible to identify a night view shooting scene, a nighttime or indoor shooting scene, or a close-up shooting scene. Furthermore,
By using subject distance data in addition to strobe light emission data and subject brightness data, it is possible to identify a daytime synchronized photography scene in addition to a night view photography scene, a nighttime or indoor photography scene, a close-up photography scene.
Therefore, it is possible to determine an appropriate printing exposure amount according to the characteristics of these scenes.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a photographic camera embodying the present invention. FIG. 2 is an explanatory diagram showing an example of the camera posture detection device. FIG. 3 is a plan view of a photographic film showing an example of recording photographing condition data. FIG. 4 is a schematic diagram of a photographic printer embodying the present invention. 5 to 7 are explanatory views showing areas when the camera posture is set to the horizontal position. 8 to 10 are flowcharts showing examples of scene classification. 10 …… Shooting lens 11 …… Shutter mechanism 17 …… Photo film 22 …… Photometry unit 26 …… Distance measuring sensor unit 36 …… Strobe device 35 …… Camera attitude detector 39 …… Bar code recorder 72 …… Bar Code reader 77 ... Scanner.

Claims (3)

(57) [Claims] 1. Strobe light emission data and subject brightness data are recorded at the time of taking a photograph, these data are read at the time of printing a photograph, and the scenes of the frames are classified according to the presence or absence of the strobe photography and the subject brightness. A method for photographic printing, which comprises calculating a printing exposure amount of a frame by selecting a printing exposure amount calculation method such as a calculation formula prepared in advance. 2. Strobe emission data and subject distance data are recorded at the time of taking a photograph, these data are read at the time of printing a photograph, and the scenes of the frames are classified according to the presence or absence of the strobe photographing and the subject distance. A method for photographic printing, which comprises calculating a printing exposure amount of a frame by selecting a printing exposure amount calculation method such as a calculation formula prepared in advance. 3. Strobe light emission data, subject distance data, and subject brightness data are recorded at the time of photographing, and these data are read at the time of printing a photograph, and the scene scenes are classified according to the presence or absence of strobe photographing, the subject distance, and the subject brightness. And a printing exposure amount calculation method such as a calculation formula prepared for each scene is selected to calculate the printing exposure amount of the frame.