JPH0666020B2 - Camera-film system - Google Patents

Description

The present invention relates to a camera-film system including a camera and a film, and more specifically, a film magazine is provided with coded electrical contacts capable of electrically detecting the film sensitivity. The present invention relates to a camera-film system in which this is detected on the camera side and film sensitivity is automatically set in the exposure control of the camera.

The camera and the film have a close relationship with each other, and when adopting a new method, there are many cases in which either one cannot be used. That is, for example, when a new structure or means provided on the film side is used on the camera side, the camera side must be modified. In this way, the system is called a camera-film system from the combination of the camera and the film which can be realized only by both the camera and the film.

(Prior art) Film magazine (In addition to the general 35 mm film container called a Patrone, the film container to be loaded into the camera is a magazine for a special camera, a cartridge,
Various things such as film packs are known, and there is a point that they are not unified such as calling different kinds of the same kind depending on the country, but these are collectively referred to as film magazine or magaji here. It has long been known to provide a means for setting the sensitivity of the film contained therein in a mechanically or electrically detectable manner. However, since the mechanism for detection is different and the sensitivity detection device on the camera side must be changed for each magazine, it must be manufactured.Therefore, from a special magazine and a special type of camera manufactured to match It has been put into practical use only with a special system, or limited to those that use a special magazine such as an 8 mm camera.

Recently, as ISO400 high-sensitivity film has been developed and spread to general-purpose color film, ISO100 film and IS
In order to automatically detect the O400 film on the camera side, a film magazine with an electrically detectable sensitivity display has been developed and put into practical use.

This is a standard ISO100 film and a high-sensitivity ISO400 film.
Although it is possible to set the automatic sensitivity between the films of the above, the sensitivity of other films cannot be set automatically. At present, these two types of film are the mainstream in Japan, and it is convenient to some extent if such sensitivity detection is possible, but it is widely used internationally in response to various films having ISO sensitivity series sensitivity. There is a problem that it is not possible to make a camera that can be used effectively, and the film used is limited to a specific film. So IS widely
A method that covers the sensitivities of the O sensitivity series is desired.

As a film magazine with a wide range of various sensitivities and a sensitivity setting contact that can be detected electrically, Jitsuko Sho 53-3153
The one described in US Pat. No. 4,024,557 is known. This is to display the sensitivity of ASA16 to ASA1000 by a coded sensitivity display consisting of five electrical contacts, but this method has not been put to practical use either.

(Problems to be solved by the invention) Various factors may be considered as the reasons why these film sensitivity display methods are not widely used, but the main reason is that the methods have become internationally standardized. No, the various schemes were simply announced separately, and
This is because it is not suitable for standardization. Therefore, an excellent method suitable for international standardization is desired.

In order to realize standardization, the sensitivity that satisfies the ISO sensitivity series, that is, the sensitivity of commercially available films and the sensitivity of films that are likely to be marketed in the future, is widely covered, and the detection mechanism is easy to implement. Must. One example of the above-mentioned method (Fig. 6 of JP-B-53-31539), which is widely known to have a sensitivity setting contact that can detect a wide variety of sensitivities, is shown in ASA16 to 1000. ISO
In the sensitivity series, three sensitivities of ASA25,250,500 are missing. In order to fill this, the number of contacts must be increased by one from 5 to 6, and in order to deal with all the sensitivities, six contact detection means must be provided on the camera side. Since the mechanism for detecting the six contact points is complicated in terms of circuit and is also high in cost, it is practically difficult to provide this detecting device in cameras of all models.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a camera-film system that widely covers the sensitivity of the ISO sensitivity series and employs a film sensitivity setting method that can be detected by a detection mechanism having a simple structure.

Further, according to the present invention, the contacts for sensitivity display are divided into two groups, one for coarse display and one for precision display, and rough display is possible with a small number of contacts. It is possible to set a rough sensitivity by dividing it into two parts, and in a high-end model, it is possible to make a precise display with a large number of contacts for precise setting, and it is not necessary to equip all cameras with an expensive sensitivity detection device. The purpose is to provide a system.

(Means for Solving the Problems) A camera-film system of the present invention is provided on a film magazine and is provided with an electrical contact for sensitivity display, which is provided for coarse display in which sensitivity display is selectively provided at three positions. An electric contact and an electric contact for precision display selectively provided at two positions are provided, and both are arranged side by side on a magazine, and depending on the camera, only the electric contact for coarse display is a detection target. It is characterized in that it is possible to perform detection with all sensitivity simply by providing a simple detection device having a small structure. High-end machines can detect the contacts of both groups of five and enable precise sensitivity setting.

More specifically, the sensitivity setting contact in the camera-film system of the present invention has three electrical contacts, first to third, arranged in a predetermined order, the first for double and the second for four. Three
Is a contact for 16 times, and in addition to this, two electrical contacts, the 4th and 5th, are further arranged in this order, and the 4th and 5th are 2 contacts.
^As a contact for ^1/3 times and 2 ^2/3 times (for example, 4th is for 2 ^1/3 times, 5th is for 2 ^2/3 times), and ISO sensitivity is displayed by the product of these. It is the one.

(Action and effect) As a result, when 2 ^3/3 times and 2 ^2/3 contacts are not used, 2 ^1/3 times (1 step higher sensitivity) and ^2/3 times the sensitivity of 2n times the basic sensitivity Sensitivity (sensitivity two steps higher) will also be detected as 2n times, and the exposure control means will operate as sensitivity of 2n times.

In this way, the exposure for the film having the sensitivity of 1 step lower and 2 steps lower than that of the film having the sensitivity of 1 step above and 2 steps above means that the film is exposed by 1 step and 2 steps. Although exposure is provided, such an exposure error does not pose a practical problem. Therefore, even if only the first to third contacts among the five sensitivity setting contacts are used, the color negative film, which is most frequently used at the present time, can perform proper exposure control without any practical problems.

Therefore, it is possible to install a simple sensitivity detection device in a popular machine and a precise sensitivity detection device in a high-class machine.

Further, the sensitivity contacts can cover all 19 kinds of film sensitivities in the ISO sensitivity series.

(Example) A camera according to an embodiment of the present invention will be described below with reference to the drawings.
The film system will be described in detail.

FIG. 1 shows a film magazine used in the system of the present invention, which is a film magazine (JI) for 35 mm roll film (J135).
FIG. 2 is a partially enlarged sectional view taken along line II-II of FIG. 2 showing an example applied to SK7528). This film magazine 10
Is to selectively provide the common contact 1 and the five electrical contacts 2, 3, 4, 5, 6 on the surface portion 13 of the cylindrical body 11 adjacent to the acute angle (in cross section) side of the film extraction slit 12. It is the one. The electrical contacts 1 to 6 are insulating layers made of resin or the like applied to the surface of the conductive metal surface of the magazine body 11.
It can be formed by removing 14.

The above-mentioned electrical contacts 2 to 6 are contacts 2 for sensitivity 2 display, sensitivity 4
Precision display consisting of coarse display contact groups 2-4 consisting of double display contact 3 and sensitivity 16x display contact 4, sensitivity 2 ^1/3 times display contact 5, sensitivity 2 ^2/3 times display contact 6 If the basic sensitivity is ISO25, the sensitivity ranges from ISO25 to 1600 can be displayed, as shown in Table 2 below.

The ISO sensitivity has a mathematical display and a logarithmic display. The former has the same value as the conventional ASA sensitivity and the same as the latter conventional DIN sensitivity. In this specification, the sensitivity ISO
This will be explained using sensitivity. That is, in this specification, ISO
Sensitivity, or sensitivity, means the sensitivity of arithmetic display, and the multiple display such as 2 times and 4 times is based on the fact that the ISO sensitivity value of arithmetic display becomes a series of multiples. Therefore,
In the case of a logarithmic display series in which the value of sensitivity increases in a uniform manner, the above multiple is read as the difference.

In addition, in Table 2, the contacts of ISO sensitivity 1600 are common x 4 x 16
In other words, it is 1,3,4, but this is common × 2 × 16
It may be × 2 ^1/3 × 2 ^2/3 . Similarly, ISO sensitivity 1
The common x4 of 00 may be common ^{x2x2 1/3} x2 ^2/3 , but the former with less contacts is preferable in practice. However, if the latter is preferable due to a special request from the detection side of the camera, the latter can be adopted.

Of the ISO sensitivities of the films shown in Table 2 above, there are no commercially available films for 320,460,800,1250,1600 marked with *, but naturally they are included in the sensitivity series or follow this. It is included in consideration of future possibility.

The sensitivity setting electrical contacts 2 to 6 as described above can be easily detected by means for electrically detecting the presence or absence (combination) of 3 to 4 or all 2 to 6 among them. Can provide film sensitivity information to the camera's automatic exposure device. Various detecting devices are conceivable for that purpose, and any type can be used. A simple example of such a device is shown in FIG.

FIG. 3 shows a film sensitivity information input means for giving film sensitivity information as a resistance value between a pair of terminals X and Y. One terminal X is directly connected to the common contact 1, and the other terminal Y is the first
~ Different resistance R2 for each of the 5th contacts 2-6 ~
Connected via R6. A resistor R1 for basic sensitivity is connected between the terminals X and Y. Since the contacts 1 to 6 are directly connected to the conductive metal portion of the film magazine main body 11, the resistors R1 to R6 are connected in parallel to each other through the portion where the surface is conductive, that is, the contact. The current flowing between the terminals XY through these resistors is controlled according to the size of the resistors (film sensitivity). That is, by changing the size of each resistor, the current flowing between the terminals XY can be changed according to the sensitivity, and this can electrically detect the sensitivity of the sensitivity.

Next, an example of an exposure control circuit equipped with a film sensitivity detection circuit of a camera using a resistance circuit as shown in FIG. 3 will be described with reference to FIG.

In FIG. 4, CdS is a light-receiving element whose resistance value changes in accordance with the brightness of the object, R is an adjusting resistor which corresponds to R1 and represents the basic sensitivity, R _A , R _B , R _C , R _D and R. _As shown in Table 2, _E is a resistor that forms a resistor network for changing the combined resistance in an analog manner together with the adjusting resistor R according to the digitally coded film sensitivity, and C is the resistor network and the light receiving element CdS. , S _A , S _B , S _C , S _D and S _E are capacitors for determining the time constant along with the equivalent resistance of S, S _B , S _C , S _D and S _E, and the detection contact provided on the camera is a conductive contact for setting the sensitivity. It is closed when it contacts with 2 to 6 and opened when it contacts with the non-conductive part. In order to carry out the DA conversion according to the film sensitivity as shown in Table 2, It is good to decide by the relationship.

Tr ₁ and Tr ₂ are NPN transistors, and the load of Tr ₂ is a magnet M that controls shutter blades (rear curtain).
The light receiving element CdS is connected in series with the resistance network, and the resistance network is further connected in series with the time constant determining capacitor C to form a time constant circuit. A switch S1 that is turned off immediately before the start of the shutter front curtain is connected in parallel to the capacitor C. This switch S1 turns on when the shutter release button returns. Connection point P between the capacitor C and the resistor network is connected to the first base of the transistor Tr _1, the first collector of the transistor Tr ₁ is connected to the second base of the transistor Tr _2, depending on the time constant Tr ₁
Is turned on and Tr ₂ is turned off. These circuits are connected to the power source E via the main switch S2.

When the film magazine is loaded into the camera having the circuit as shown in FIG. 4 as described above, if the common contact and the second conductive contacts 1 and 3 have an ISO sensitivity of 100, they are common. Adjusting resistor R by contact 1 and second contact 3
The combined resistance of the resistor R _B and the resistor R _B is connected in series to the light receiving element CdS. Then, when you press the shutter release button, the main switch S2 turns on first. At this time, the switch S1 is ON. Next, the mechanically locked member for starting the shutter front curtain is released, and the switch S1 opens (OFF) at the same time when the front curtain starts. At this point, the first transistor Tr ₁ is off and the second transistor Tr ₂ is on, and the shutter rear curtain holding member is attracted and locked by the magnet M. At the same time when the switch S1 is opened, the time constant circuit composed of the light receiving element CdS, the resistor networks R, _{RA to} R _E , and the capacitor C starts to operate, and the light receiving element
Equivalent resistance value of CdS, combined resistance of resistance network (in this case R and R
After the elapse of the time constant determined by the combined resistance of _B ) and the capacitance of the capacitor C, the first transistor Tr ₁ is turned on, and the second transistor Tr ₂ is turned off. Therefore, the magnet M loses its attractive force, the rear curtain holding member is released, the rear curtain of the shutter is closed, and the exposure is completed. Then, when the release button returns, the switch S1 returns to ON, and the exposure sequence is completed.

As described above, if the film magazine as described above is used, the exposure can be easily controlled by using the contact for setting the sensitivity.

In addition, the camera-film system of the present invention contacts the film sensitivity within an error within a range in which the exposure is over two steps even with only the total of four contacts 1 to 4 from the common contact to the third contact as described above. Therefore, if you install a device that detects three contacts on the camera side, for example from ISO25 to 1600
Up to 19 types of film sensitivity can be detected.
Therefore, in addition to a high-end machine in which the camera is provided with a device for detecting a common contact and all five contacts, a popular machine having a device for detecting three contacts can be manufactured, which is suitable for practical use.

Furthermore, in the case of this example, since it covers a wide range of 19 film sensitivities from ISO 25 to 1600, it is internationally wide and not only all the films currently on the market but also the possibility of being developed and released in the future. Sensitivity can be displayed for most existing films, and it is suitable for international standards.

In the examples of FIGS. 3 and 4, the adjustment resistors R and R ₁ are always set to the time constant circuit so that the exposure control device automatically operates even when the film magazine has no contacts. Although it is supposed to be connected, in this case the exposure control will be performed in the same state as when the ISO speed is the basic speed. Therefore, in this case, the adjusting resistors R and R ₁ may be variable resistors, and it may be manually considered according to the size sensitivity of R and R ₁ . Alternatively, in this case, a warning signal without contacts may be generated, and a variable resistor may be manually connected separately in parallel with the resistor network.
The adjusting resistors R, R ₁ may be variable and may be manually set.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of a film magazine used in a camera-film system of the present invention, FIG. 2 is a partially enlarged sectional view taken along the line II-II, and FIG. FIG. 4 is a circuit diagram showing an example of a resistance circuit for electrically detecting a sensitivity display in the camera of the camera-film system of FIG. 4, and FIG. 4 is a circuit diagram showing a more specific example thereof together with the exposure control circuit of the camera. 1 …… Common contact 2,3,4 …… Contact for rough film sensitivity display 5,6 …… Contact for precise film sensitivity display 10 …… Film magazine 11 …… Magazine body 12 …… Film take-out slit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-51-128525 (JP, A) JP-A-52-53420 (JP, A) Actual development-Sho 51-21336 (JP, U) Actual publication S-49- 4385 (JP, Y1)

Claims (1)

[Claims] 1. A camera-film system comprising a film magazine containing a film therein and a camera in which the film magazine is loaded, wherein the first, second and third films are electrically contactable from the outside of the film magazine. , 4th
And film sensitivity setting contacts coded according to the sensitivity of the film are provided at five positions,
And the first and second contacts of the coarse sensitivity display are provided in the third and third positions.
A contact point, a second contact point and a third contact point are selectively provided, respectively, and a fourth contact point and a fifth contact point of the precision precision display contact point are selectively provided at the fourth and fifth positions, respectively. One contact was used as the contact for displaying the sensitivity twice, the second contact was used as the contact for displaying the sensitivity four times, the third contact was used as the contact for displaying the sensitivity six times, and the fourth contact and the fifth contact were connected with the sensitivity 2 ^1/3. And a sensitivity 2 ^2/3 times display, the camera is provided with a coarse detection contact that contacts only the coarse display contact among the sensitivity setting contacts selectively provided at the five positions. The popular camera and / or the high-end camera equipped with precision detection contacts that come in contact with all contacts are used.By doing so, the rough and precise settings of the film sensitivity can be selectively performed by the camera. Characteristic Camera-Filmsys Beam.