JPH07128704A - Film, cartridge for film and camera - Google Patents

Abstract

PURPOSE:To usefully exchange much more information between a camera and film, and to execute direct photometry with high accuracy by previously record ing data about surface reflectance on a photosensitive surface side. CONSTITUTION:Operation for recording and reproducing magnetic information is controlled by a microprocessor 26 through a read/write electronic circuit 25. Since the surface reflectance on the photosensitive surface side of the film, which is divided into spectral reflectance in a visible light area and an infrared area, is previously recorded on a film magnetic layer in addition to information inherent in the film, the microprocessor 26 reads the information by using a magnetic head 24 so as to transfer it to an E<2>PROM in a potential circuit for controlling a camera through a main CPU 27 or so as to magnetically record information inputted by a camera user through a controller 28 and photographing information at the time of photographing by a sensor 29. Thus, the information is previously recorded on the film and read by the camera, so that the direct photometry with high accuracy is executed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film or a film cartridge in which film information relating to exposure is recorded in advance, and a camera for performing exposure control using this film or film cartridge.

[0002]

2. Description of the Related Art It is now widely practiced to record film sensitivity, filmable number and latitude film information in advance on a film cartridge, and a camera can selectively read and use these when the film is loaded.

As a means for easily exchanging information in a photographic system, a system in which a substantially transparent magnetic recording layer is coated on the back surface of the film and necessary information is directly recorded on the magnetic layer of the film is an international application. WO-90 / 04205, WO-
90/04214, US Patents USP-4965627, USP-4975732 and the like. That is, the manufacturer name at the time of film production,
Record the film type, emulsion lot, sensitivity, date of manufacture, reference signal, etc., and record the shooting conditions, such as color temperature of the light source, subject brightness, exposure time, aperture value, presence of backlight, presence of flash emission, continuous The presence / absence of a photograph, the type of camera, the owner ID, the date of photographing, the memo of the photographer, etc. are recorded for each frame. Further, at the DPE reception window, the customer's order information such as print size, number of prints, desired finish of silk or gloss is recorded on the film. At the time of printing, these pieces of information are read out from the film, and the printing conditions are determined together with the optical density data obtained by scanning the negative. As a result, it is possible to obtain a print that reflects the shooting situation and shooting intention, and if you record this exposure condition for each frame, read it out when printing, and print it, you can obtain a print with the same color tone as the first. Has been done.

[0004]

As a kind of TTL metering method, there is a metering method called direct metering in which a light receiving element is directed to the film surface inside the camera and the amount of light directly hitting the film surface is measured. It was considered that the surface reflectances of all films were almost constant, and the exposure was controlled by the amount of reflected light and the film sensitivity on the basis of this. However, depending on the type of film, the surface reflectance varies from 23% to 31%, and with minicopy films, the reflectance differs from 10% to several percent, and even with the same sensitivity, the exposure amount varies depending on the film. In particular, when a reversal film having a narrow latitude is used, variations in exposure amount pose a problem. Further, the reflectance in the visible light region may be used for the stationary light exposure, and the reflectance in the infrared light region may be used for the strobe exposure, but there is no way but to control the reflectance by considering it as a constant value.

This is because the film does not have information on the reflectance which differs depending on the film, and therefore the camera side cannot cope with it. Therefore, the first object of the present invention is to obtain proper exposure by adding information on the surface reflectance to the conventional film information.

Further, the film sensitivity of the DX code displayed on the cartridge is read and used as information for exposure control, but the film sensitivity changes with the lapse of time after manufacturing. However, in the current film, the average sensitivity is uniquely expressed, and since the camera controls the exposure based only on the sensitivity information, there is a difference in the film density immediately after the film is manufactured and near the expiration.

Furthermore, the expiration date of the film is written on the film packaging box, but the user only judges it by looking at it, and after loading it in the camera, the user will not know even if the expiration date has passed. Absent.

Further, in the date mechanism for imprinting date characters from the back surface of the photosensitive surface of the film, even if the sensitivity on the emulsion surface side is the same, the character density is greatly different due to the difference in the layer design. It is not possible to maintain uniform imprint quality.

As described above, with respect to the change in film sensitivity with time and the difference in sensitivity from the back surface of the film, by recording these information on the film in advance, the camera side reads the information and obtains the proper exposure. Is the second object of the present invention.

As described above, according to the present invention, in addition to the conventional film information described above, new information is recorded on the film in advance, so that more useful information exchange between the camera and the film becomes possible. The camera can easily cope with what was impossible in the past.

[0011]

According to the present invention, there is provided a reading means for reading surface reflectance data on the photosensitive surface side of a film or a film cartridge recorded in the film cartridge, and the surface read by the reading means. A camera comprising an exposure control means for performing exposure control based on reflectance data and film sensitivity, a manufacturing date, a use-by date, and a use-from-manufacturing date pre-recorded on the film. A reading means for reading each data of the average sensitivity and the amount of change in sensitivity up to the year, a clock means for at least marking the year and a month, and a current film by comparing each data read by the reading means with the current year by the clock means. Calculation means for calculating the sensitivity, and exposure control for performing exposure control based on the current film sensitivity calculated by the calculation means. A camera characterized by including a control means, and a reading means for reading back sensitivity data when irradiating a non-photosensitive surface side from a predetermined light source recorded in advance on the film, and the reading means read by the reading means. A camera is characterized in that the imprinting time is adjusted based on the back side sensitivity and the date means provided on the non-photosensitive surface side of the film is provided.

[0012]

Embodiments of the present invention will be described with reference to FIGS.
The details will be described.

The first embodiment is a camera in which the surface reflectance on the photosensitive surface side of the film is recorded in advance on the film and the exposure is controlled based on the recorded information. A camera in which the above information is recorded on a film in advance and the exposure is controlled based on the recorded information will be described as a second embodiment.

FIG. 1 is a diagram in which the present invention is applied to the film disclosed in Japanese Patent Publication No. 4-501021, which is common to the first and second embodiments.

In FIG. 1, F is a film having a non-photosensitive surface coated with a magnetic layer. Reference numerals 1 to 4 are magnetic tracks, and two magnetic tracks are provided on both outer sides of the photographing screen 5. The photographing conditions described above are written in the photographing frames 1 to 25, and the photographing frames 0 and 26 are recorded. Since the film sensitivity and other film information is magnetically recorded at the time of film production, these are read out and used when the film is loaded into the camera. Reference numeral 6 denotes a transparent magnetic layer coated in the photographing screen 5, which is composed of 30 thin tracks and magnetically records customer order information at the DPE window. Reference numeral 7 is a perforation for positioning when the film is fed.

In the present invention, new information is magnetically recorded on at least one of the magnetic tracks 1 to 4 on the photographing frames 0 and 26 in addition to the conventional film information.

In the first embodiment, the surface reflectance of the photosensitive surface of the film is magnetically recorded during manufacture. In particular, in consideration of stroboscopic photography, it is better to divide the surface reflectance into a visible light region and a spectral reflectance in the infrared region, and record each data magnetically.

In the second embodiment, the data of the film manufacturing date, the expiration date, the average sensitivity from the manufacturing date to the expiration date, and the sensitivity change amount are magnetically recorded at the time of production. Further, back sensitivity data when the non-photosensitive surface of the film is irradiated with light from a predetermined light source is also magnetically recorded at the time of manufacturing.

FIG. 2 is a conceptual diagram of a camera suitable for reading and writing data on the film of FIG. 1, and is common to the first and second embodiments.

Reference numeral 21 denotes a camera main body, which stores the film F, which is housed in the cartridge C and wound around the spool Ca, on the take-up reel 21a to feed the film. twenty two
Is a taking lens, and exposes the photosensitive surface of the film F.
A magnetic head 24 is provided on the back surface of the film F, that is, the non-photosensitive surface, penetrating the pressure plate 23, and contacts with any of the magnetic tracks 1 to 4 in FIG. 1 to record and reproduce information on the magnetic layer. The operation of recording and reproducing magnetic information is controlled by the microprocessor 26 via the read / write electronic circuit 25.
In the magnetic layer of the film, in addition to the information peculiar to the film that has been conventionally used, the surface reflectance on the photosensitive surface side of the film is divided into a visible light region and a spectral reflectance in the infrared region and recorded in advance. Therefore, the microprocessor 26 reads this information with the magnetic head 24, and the main CPU 27
E ₂ in the camera control electronic circuit not shown via
Information can be transferred to the PROM, information input by the camera user via the controller 28, and shooting information at the time of shooting by the sensor 29 can be magnetically recorded. A date module 30 is provided behind the pressure plate 23 to imprint date characters from the back surface of the film F.

FIG. 3 is a diagram of an electronic circuit block of the camera. Most of the electronic circuit block is the same as that of the conventional camera, except that the main CPU 31 and the magnetic information circuit 32 exchange information with each other. Although an internal photometric circuit 33 is added to the conventional external photometric circuit 34, the internal photometric circuit 33 is unnecessary in the second embodiment.

FIG. 4 is a sectional view of the camera used in the first embodiment. The photographing light transmitted through the photographing lens 41 is exposed to the film F, but a part of the light is reflected by the photosensitive surface of the film F, and the reflected light is transmitted through the internal photometric lens 42 and the internal photometric element 43. And is converted into an electric signal. Reference numeral 44 is an external light metering lens, and 45 is an external light metering element, which is used as information for determining whether or not the flash can be used and displaying information in the finder 46 by measuring the external light luminance level in advance.

FIG. 5 is a flow chart for the camera of the first embodiment. The film F is loaded in FIG. 1, the rear cover switch S _B is ON (101) closes the back cover. As a result, the film starts to be fed (102), and the data recorded in advance on the film is read (103).
This data includes, in addition to the ISO sensitivity data and the like shown in the conventional example, surface reflectance data in the visible region and the infrared region, which is the invention of the present application. When the first frame for photography is detected (104), the film feeding stops (10
5) Do. Next, the light quantity threshold level of the internal photometric system is set (106). The internal photometric element 43 in FIG. 4 uses an SPD with good response, and when controlling using visible range data, an infrared cut filter is provided in front of the internal photometric element 43 to control the infrared range data. When using, no infrared cut filter is required. Further, this internal photometric circuit integrates the received light amount, and if the film sensitivity and the film reflectance are determined, the integrated value of the received light amount with respect to the proper exposure amount becomes constant, and the integrated value of this light amount value is set as the threshold level. It is a thing. Further, this level may be a value obtained by estimating the response delay amount and subtracting that amount. The process up to this point is performed when the film is loaded, and the state of waiting for shooting is set.

Next, the photographing stage will be described. S ₁ by half pressing of the release switch is ON (107), ranging (108) is performed, further the object brightness measured (109) by an external metering system 44 and 45 in FIG. 4, in flash or ambient light shooting If it is judged that it is flash light (110), (110)
Y) starts strobe charging (111) and completes charging (1
By (12), charging is stopped (113). When it is determined that the fixed light imaging (110 N), the process directly proceeds (114), after the S ₂ is the pressing of the further release switch is ON (115), achieved focus by driving the lens (116), The internal photometry systems 42 and 43 in FIG. 4 start photometry (117). After that, the shutter is opened (118) and the strobe circuit is triggered (119). At this time, if the strobe circuit is in a charging completed state, it starts emitting light, and does not emit light when not charging. A conventionally known so-called dimming strobe is used for this strobe circuit. Internal photometric system of Figure 4
The photometric circuits 42 and 43 integrate the reflected light from the film surface during exposure, and when the threshold level is reached (Y at 120), the sequence proceeds to stop the exposure. That is, the flash light emission stop (121) and the shutter close drive (122) are performed. In addition, the internal metering system stops functioning (12
3), and after returning the taking lens to the initial position (124),
Film feeding is started (125), and shooting-related information and the like are magnetically recorded (126). Next, at the time when the film feeding for one frame is completed, if the next frame is a frame for shooting (1 to 25 frames) (Y of 127), the film feeding is stopped (128), and the filming standby state is set. On the other hand, on the other hand, in the case of a frame (26 frames) which is not a frame for photographing (N of 127), film rewinding (129) is performed, and when the rewinding is completed (Y of 130), a series of flows is stopped.

FIG. 6 is a flow chart for the camera of the second embodiment. The film F is loaded in FIG. 1, the rear cover switch S _B is ON (201) closes the back cover. As a result, the film starts to be fed (202), and the data previously recorded on the film is read (203).
This data is, in addition to the data shown in the conventional example, the production date, the expiration date, the average sensitivity and the amount of change in sensitivity from the production date to the expiration date, which is the invention of the present application, and a predetermined light source. It includes the back side sensitivity when irradiated to the non-photosensitive side on the back side of the film. Then, the shooting frame is detected (204)
At that point, the film feeding is stopped (205). After this, the current date and time is read from the clock of the main CPU in the camera or the clock of the DATE module (206), first compared with the expiration date of the film information, and if the current date and time exceeds the expiration date (N of 207). ), LCD outside the camera
After issuing a warning on the display (208), the film is rewound to the initial position (209, 210), and the camera function is stopped (211). In this flow, when the expiration date is exceeded, the function is stopped. However, for example, only a warning may be displayed near the deadline within 3 months, and if the deadline is exceeded, the function may be stopped. You don't have to.

When the film is judged to be within the time limit (207
Y) of the next step, obtain the difference between the manufacturing date in the read data and the current date, that is, the elapsed time after manufacturing, and calculate the average sensitivity and the sensitivity change amount from the manufacturing date to the expiration date. The current sensitivity is calculated (212).

For example, as shown in FIG. 7, the manufacturing date is 19
In June 1995, the expiration date was set to June 1997,
The sensitivity of June 1996 is set equal to the average sensitivity of the manufacturing date and the expiration date, and this is set as the reference sensitivity. In this example, ISO 100 is assumed, and the amount of change in sensitivity between the manufacturing year and the intermediate year, and the intermediate year and the expiration date is 1/3 EV. Here, for example, when January 1996 is the current year and month, the sensitivity of the current year and month can be calculated as ISO100 + 1 / 6EV, so by using this value for exposure control, more precise exposure can be given. .

Further, of the read data, the date imprinting time is determined (213) based on the back side sensitivity information.

The process up to this point is performed when the film is loaded, and the state of waiting for photographing is set.

After that, the sequence is the same as that of a normal camera, and S ₁ is turned on by pressing the release switch halfway.
(214) is performed, distance measurement (215) and photometry (216) are performed, the exposure value is determined (217) by the sensitivity and photometric value of the current year and month calculated as described above, and the release switch is pressed (218). Thus, S ₂ is turned on (219), the lens is driven (220), the focus is adjusted, and then the shutter is driven (221) based on the exposure amount described above, and the date is imprinted based on the date imprinting time. (222) is performed.
This completes shooting and returns the lens to the initial position (22
After 3), the film feeding is started (224) and the shooting-related information is magnetically recorded (225). Next, when the next frame is 1 to 25 frames (Y of 226), when feeding of one frame is completed (227), the process returns to the point before reading the current date and time. On the other hand, if the number of frames is not 26 for shooting, rewind the film (228),
When the rewinding is completed (229), the series of flows is stopped.

In the above embodiment, the newly added film information is recorded on any one of the magnetic tracks 1, 2, 3 or 4 in FIG. 1, but the transparent magnetic layer 6 applied inside the photographing screen 5 is recorded. It may be recorded on any of the 30 narrow tracks.

A conventional Patrone DX code may be added, or a code pattern that rotates with a spool described in a known document may be used.

In addition, a raster cord having a hole in the tongue of the film may be used.

[0034]

As described in detail above, according to the present invention, even if the surface reflectance on the photosensitive surface side differs depending on the type of film, the information is recorded in advance on the film and the information is recorded by the camera. Since it can be read, highly accurate direct photometry can be performed, and in a camera that performs photometry separately for films with different spectral reflectance in the visible light region and infrared region, the difference in exposure amount is eliminated by each information. be able to.

Further, since the change in sensitivity with time of the film is recorded on the film in advance and the camera detects the sensitivity at the time of photographing, precise exposure control becomes possible,
Particularly, it is more effective for a reversal film having a narrow latitude.

Further, it is possible to prevent a defective photograph from being used because the expired film is unknowingly used or the film is loaded into the camera for a long period of time to expire.

Moreover, since the film also records the sensitivity when a predetermined light source is irradiated from the back surface of the film, the quality of date characters projected from the back surface of the film is uniform regardless of the film.

[Brief description of drawings]

FIG. 1 is a diagram of a film used in the present invention.

FIG. 2 is a conceptual diagram of a camera used in the present invention.

FIG. 3 is a block diagram of an electronic circuit of a camera used in the present invention.

FIG. 4 is a sectional view of a camera used in the first embodiment.

FIG. 5 is a flowchart of the camera of the first embodiment.

FIG. 6 is a flowchart of the camera of the second embodiment.

FIG. 7 is a diagram showing a change in sensitivity with time.

[Explanation of symbols]

 F film C cartridge 1, 2, 3, 4 Magnetic track 22, 41 Lens 24 Magnetic head 30 Date module 43 Internal photometric element 45 External photometric element

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display location G03C 3/00 572 D 8909-2H G11B 5/00 Z 7426-5D

Claims (14)

[Claims] 1. A film having pre-recorded data on the surface reflectance on the photosensitive surface side. 2. The film according to claim 1, wherein a magnetic layer is coated on the non-photosensitive surface side and the surface reflectance data is recorded on the magnetic layer. 3. A film cartridge, wherein surface reflectance data on the photosensitive surface side of the film is recorded in advance. 4. The film according to claim 1 or 2, wherein the surface reflectance is divided into a spectral reflectance in a visible light region and a spectral reflectance in an infrared region, and the respective data are recorded. 3. The film cartridge according to item 3. 5. A reading means for reading the surface reflectance data on the photosensitive surface side of the film or the film recorded in the film cartridge, and based on the surface reflectance data and the film sensitivity read by the reading means. A camera provided with an exposure control means for performing exposure control. 6. A film characterized in that the production date, the expiration date, the average sensitivity from the production date to the expiration date, and each data of the sensitivity change amount are recorded in advance. 7. A film cartridge characterized in that each data of manufacturing date, expiration date, average sensitivity from the manufacturing date to expiration date, and sensitivity change amount is recorded in advance. 8. The film according to claim 7, wherein a magnetic layer is coated on the non-photosensitive surface side and the respective data are recorded on the magnetic layer. 9. A reading means for reading each data of the manufacturing date, the expiration date, the average sensitivity from the manufacturing date to the expiration date and the sensitivity change amount recorded in advance on the film,
At least clock means for marking the year and month, computing means for computing the current film sensitivity by comparing each data read by the reading means with the current date by the clock means, and the current film sensitivity computed by the computing means And an exposure control means for performing exposure control based on the camera. 10. A reading means for reading expiration date data recorded in advance on a film, a clock means for engraving at least a year and a month, the expiration date data read by the reading means and a current year and month by the clock means are compared. ,
A camera, comprising: a comparison unit that outputs when the current year / month approaches the expiration date, and a control unit that controls a warning or prohibition of camera operation by the output of the comparison unit. 11. A film on which back sensitivity data when irradiated to a non-photosensitive surface side from a predetermined light source is recorded in advance. 12. The film according to claim 11, wherein a magnetic layer is coated on the non-photosensitive surface side, and the back side sensitivity data is recorded on the magnetic layer. 13. A film cartridge in which back sensitivity data when irradiated from a predetermined light source to the non-photosensitive surface side is recorded in advance. 14. A reading unit for reading back sensitivity data when a non-photosensitive surface side is irradiated with light from a predetermined light source previously recorded on a film, and an imprinting time is adjusted based on the back sensitivity read by the reading unit. A camera provided with a date means provided on the non-photosensitive surface side of the regular film.