JPH04293038A - Camera provided with magnetic head - Google Patents

Abstract

PURPOSE:To offer a camera provided with a magnetic head in which erroneous information is prevented from being recorded. CONSTITUTION:This camera is provided with a film feeding means 102 for feeding the frame of a film 101 after photographing, the magnetic head 103 for recording information on a magnetic recording area provided on the film as the frame of the film 101 is fed, a pad 104 which can be switched to a projecting position where the magnetic recording area of the film 101 is pressed to the magnetic head 103 in a state where the film 101 is held between the pad 104 and the head 103 and to a retracting position where it is retracted from the film 101, and a switching control means 105 which switches and holds the pad 104 to the projecting position previous to the actuation of the head 103 under environment where a temperature is under a specified temperature and to the retracting position under the environment where the temperature is equal to or above the specified temperature.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera capable of recording information (eg, trimming information) on film using a magnetic head.

0002

[Prior art and its problems] In this type of camera, when a magnetic head is brought into contact with a film to record information, the magnetic head is brought into contact with the magnetic recording area with an appropriate pressure.
It is necessary to provide a pad at a position facing the magnetic head while sandwiching the film, and to use this pad to press the magnetic recording area against the magnetic head.

By the way, in a high-temperature environment, there is a risk that the performance of the magnetic head may deteriorate, or the magnetic head may adhere to the film, resulting in information not being recorded accurately. Therefore, in this case, it is desirable not to perform magnetic recording and to avoid pressing the magnetic head against the film, but if the magnetic head and pad are fixedly installed inside the camera body, the magnetic head always is pressed against the film, and there is a risk that erroneous information may be recorded in a high-temperature environment. Furthermore, even in a high humidity environment, the performance of the magnetic head may deteriorate, causing erroneous information to be recorded as described above.

An object of the present invention is to provide a camera having a magnetic head that prevents recording of erroneous information.

[0005]

[Means for Solving the Problems] Explaining with reference to FIG. 1(a) which is a diagram corresponding to the claims, a camera having a magnetic head according to the invention of claim 1 has a film feeding means for feeding a frame of film 101 after photographing. 102 and film 101
A magnetic head 103 records information in a magnetic recording area provided on the film as the frame is advanced;
The magnetic recording area of the film 101 is transferred to the magnetic head 1 by sandwiching the film 101.
The pad 104 can be switched to a protruding position where it is pressed against the film 101 and a retracted position where it is retracted from the film 101. Under the above environment, a switching control means 105 for switching and holding the pad 104 in the retracted position is provided, thereby solving the above problem. Further, as shown in FIG. 1(b), the camera having the magnetic head according to the invention of claim 2 includes the above-mentioned film feeding means 102, a protruding position that abuts the magnetic recording area provided on the film 101, and a retracted position where the magnetic recording area is retracted, and a magnetic head 203 that records trimming information in the magnetic recording area as the film frame advances when in the protruding position; A pad 204 that presses against the head and a magnetic head 20 in an environment below a predetermined temperature.
The above-mentioned problem is solved by switching the magnetic head 203 to the protruding position prior to the operation of 3, and switching the magnetic head 203 to the retracted position in an environment of a predetermined temperature or higher. do. Furthermore, a camera having a magnetic head according to the invention of claim 3 is provided in FIG.
The film feeding means 102 shown in (a) and the magnetic head 1
03 and a pad 104, and the switching control means 105 is configured as follows. That is, the switching control means 105 controls whether the magnetic head 20
Prior to the operation of step 3, the magnetic head 203 is switched to the protruding position, and in an environment with a predetermined humidity or higher, the magnetic head 203 is switched to the retracted position and held. Furthermore, a camera having a magnetic head according to the invention of claim 4 is provided in FIG.
) and a magnetic head 203.
and a pad 204, and the switching control means 205 is configured as follows. That is, the switching control means 20
5 switches the magnetic head 203 to the protruding position before operating the magnetic head 203 in an environment with less than a predetermined humidity, and switches the magnetic head 203 to the protruding position in an environment with a predetermined humidity or more.
3 to the retracted position.

[0006]

(1) The switching control means 105 of the invention switches the pad 104 to the protruding position before operating the magnetic head 103 in an environment below a predetermined temperature. This allows the above information to be recorded. On the other hand, when the temperature around the camera exceeds a predetermined value, that is, when there is a risk that erroneous information may be recorded, the pad 104 is switched to the retracted position and held. This prevents the magnetic head 103 from adhering to the film and from recording erroneous information. (2) In an environment where the temperature is lower than a predetermined temperature, the switching control means 205 switches the magnetic head 203 to the protruding position before operating the magnetic head 203. This allows the above information to be recorded. On the other hand, if the temperature around the camera exceeds a predetermined value,
That is, when there is a possibility that erroneous information may be recorded, the magnetic head 203 is switched and held at the retracted position. This provides the same effect as described above. (3) The switching control means 105 of the third aspect of the invention switches the pad 104 to the protruding position before operating the magnetic head 103 in an environment where the humidity is lower than a predetermined humidity. This allows the above information to be recorded. On the other hand, if the humidity around the camera exceeds a predetermined value, that is, if there is a risk that erroneous information will be recorded, the pad 104 is switched to the retracted position and held. This provides the same effect as described above. (4) The switching control means 205 of the invention switches the magnetic head 203 to the protruding position before operating the magnetic head 203 in an environment with less than a predetermined humidity. This allows the above information to be recorded. On the other hand, if the humidity around the camera exceeds the specified value,
That is, when there is a possibility that erroneous information may be recorded, the magnetic head 203 is switched and held at the retracted position. This provides the same effect as described above.

[0007]

Embodiment An embodiment in which the present invention is applied to a camera capable of cropping photography will be described with reference to FIGS. 2 to 7. Trimming photography is recording information (trimming information) to the effect that only a predetermined area (trimming area) of the exposure area formed on the film by shutter release is to be printed (trimming information), for example, in a recording area of the film. This trimming information is read at the lab, and based on it, only the trimmed area is enlarged and printed. Since the trimming area is smaller than the printing area obtained by normal photography, by performing the above-mentioned trimming photography, it is possible to obtain a photograph equivalent to a zoomed photograph even with a single focus lens.

FIG. 2 is a perspective view of the camera according to the present invention seen from the rear, and FIG. 3 is a side sectional view thereof. A main switch 41 and a release button 42 are provided on the top surface of the camera body 1, as well as a momentary type trimming switch 43, a display LED 44, and a temperature sensor 45 for detecting the temperature around the camera. The trimming switch 43 is for instructing switching between the above-mentioned trimming shooting mode for performing trimming shooting and normal shooting mode for normal shooting, and is always biased in the direction A by a spring (not shown), and is normally in the off position shown. In this off position, the normal photographing mode is commanded. Further, when the switch 43 is operated to the on position in the B direction against the biasing force of the spring, a trimming photographing mode is commanded, and when the operation is stopped, the switch 43 returns to the off state due to the biasing force of the spring. The LED 44 is lit only when the switch 43 is in the on position.

Further, in FIG. 2, inside the camera body 1, there are
A cartridge chamber 2 in which a cartridge 21 is loaded is provided at one end, a spool chamber 4 for storing a winding spool 3 is provided at the other end, and an aperture 5 is provided between these chambers. Further, a magnetic head 10 for recording information is fixedly provided below the aperture 5, and a pad 11 is attached facing the magnetic head 10.

Patrone 2 loaded in cartridge chamber 2
The film 22 pulled out from the magnetic head 10 is passed between the magnetic head 10 and the pad 11, passes immediately after the aperture 5, and is wound around the winding spool 3. When the back cover (not shown) is closed, the upper and lower ends of the film 22 are pressed against the rails 1a and 1b by the pressure plate (provided on the back cover) 12, as shown in FIG. 3, and the film 22 remains flat. The center part is the apartment.
Facing Cha. Here, a magnetic recording area 22a is provided at the bottom of the film 22 as shown in the figure, and the magnetic head 10 is brought into contact with this magnetic recording area 22a to record trimming information. Note that 6 is an outer cover that covers the camera body 1, 8 in FIG. 2 is a photographing lens, and 9 is a lens shutter provided at the rear thereof.

Here, the pad 11 is moved in the front-rear direction of the camera between the position shown in FIG. 4(a) (projected position) and the retracted position shown in FIG. 4(b) by the drive mechanism shown in FIG. It is considered possible. At the protruding position, the pad 11 presses the magnetic recording area 22a of the film 22 against the magnetic head 10, allowing the magnetic head 10 to perform magnetic recording. At this time, as shown by the solid line in FIG. A portion of the pad 11 protrudes into the optical path L of the photographing light that passes through the aperture 5 and is guided to the film 22. On the other hand, in the retracted position, the pad 11 is retracted from the photographing optical path L as shown by the two-dot chain line in FIG. Magnetic recording by head 10 is impossible.

In FIG. 4, reference numeral 31 denotes a linear guide that supports the pad 11 so that it can move only in the front-back direction, and both ends of the spring 32 are attached to the protrusion 31a of the linear guide 31 and the protrusion 11a at the rear end of the pad 11. Each is hung. The pad 11 is always urged forward, that is, toward the magnetic head 10 side, by the urging force of the spring 32. 33
is a cam integrated with the gear G1, and the cam surface 33a of this cam 33 is capable of engaging with the protrusion 11b at the rear end of the pad 11. The gear G1 is meshed with a pinion gear G2 attached to the output shaft of the motor M1, and therefore, the rotation of the motor M1 causes the cam 33 to move through the gears G1 and G2.
rotates.

SW1 and SW2 are pad position detection switches, and when the pad 11 is in the protruding position (FIG. 4(a)), the switch SW1 is turned on by the lever 33b protruding from the cam 33 (at this time, the switch SW2 is turned on). is off), and when the pad 11 is in the retracted position (FIG. 4(b)), the switch SW2 is turned on by the rear end portion 11b of the pad 11 (at this time, the switch SW1 is off).

FIG. 5 shows a control system, and the control circuit 51 includes the pad driving motor M1 and the hoisting motor M2.
A motor drive circuit 52 is connected thereto, as well as an exposure control circuit 53 for driving the shutter 9, a magnetic head 10, and a display LED 44. Furthermore, the pad position detection switches SW1, SW2 and the release button 4 described above are
Release switch SW5, which turns on in conjunction with the operation of step 2.
The main switch 41, trimming switch 43 and temperature sensor 45 are also connected to the control circuit 51, and the temperature sensor 4
5 and the on/off status of each switch are input to the control circuit 51.

Next, the control procedure by the control circuit 51 will be explained based on the flowcharts of FIGS. 6 and 7. This program is started when the main switch 41 is turned on, and when it is determined in step S101 that the main switch 41 is on, the process advances to step S201. Step S201
Then, the temperature X around the camera detected by the temperature sensor 45 is read, and it is determined whether or not this is greater than or equal to a predetermined value X1. If it is determined that it is less than the predetermined value X1, the process proceeds to step S102.

In step S102, it is determined whether the trimming switch 43 is on or off, and when it is determined that the trimming switch 43 is operated to the on position, the LED 44 is turned on.
is turned on and a trimming photographing mode is set, and the process proceeds to step S103, where the state of the release switch SW5 is determined. If the release switch SW5 is off, the process returns to step S101, and if it is on, the process returns to step S104.
Proceed to.

In step S104, it is determined whether or not the pad 11 is in the protruding position based on the state of the switch SW1.
If the switch SW1 is off, it is determined that it is not in the protruding position, that is, in the retracted position, and the process proceeds to step S106.
If the switch SW1 is on, it is determined that the pad 11 is in the protruding position, and the process proceeds to step S105, where the pad 11 is switched to the retracted position.

That is, the control circuit 51 rotates the motor M1 in a predetermined direction via the motor drive circuit 52, and rotates the motor M1 in a predetermined direction.
2. Rotate the cam 33 counterclockwise via G1. As a result, the cam surface 33a of the cam 33 comes into contact with the rear end of the pad 11 and presses it toward the rear of the camera, so that the pad 11 is guided by the linear guide 31 while resisting the biasing force of the spring 32. Driven behind the camera. When the pad 11 reaches the retracted position shown in FIG. 4(b), the switch SW2 is turned on, and in response, the control circuit 5
1 stops motor M1.

Next, in step S106, the shutter 9 is driven via the exposure control circuit 53 to take a photograph. Here, when the shutter 9 opens, the subject light passes through the zoom lens 8 and the lens shutter 9 and is guided into the camera body 1, and of this subject light, only the light that has passed through the aperture 5 reaches the film 22. Film 22 is exposed. In this state, the pad 11 is connected to the aperture 5 as shown in FIG.
Since the pad 11 is evacuated from the optical path L of the photographing light passing through the pad 11, this photographing light will not be eclipsed by the pad 11.

After photographing is completed, the pad 11 is driven to the protruding position in step S107. That is, the motor M1 is reversely rotated, and the cam 33 is rotated in the clockwise direction via the gears G2 and G1. As a result, the cam surface 33a separates from the rear part of the pad 11, so the pad 11 is driven to the protruding position shown in FIG. 4(a) by the biasing force of the spring 32, and the film 2
The second magnetic recording area 22a is pressed against the magnetic head 10, and becomes ready for magnetic recording. In this state, the switch SW1 is turned on, and the control circuit 51 stops the motor M1.

Next, in step S108, the winding spool 3 is rotated by the winding motor M2, thereby starting to wind one frame of the film 22, and at the same time, in step S109, the magnetic head 10 is driven, and the magnetic head 10 accompanying the winding operation is rotated. Trimming information is recorded in the magnetic recording area 22a by the magnetic head 10 as the recording area 22a moves. After the information recording is completed, when the completion of winding of one frame of film is detected by a detection device (not shown), the winding motor M2 is stopped in step S110, and the process returns to step S101.

Further, if it is determined in step S102 that the trimming switch 43 is in the off position, the L
The ED 44 is turned off, the normal photographing mode is set, and the process proceeds to step S111 in FIG. When it is determined in step S111 that the pad 11 is in the protruding position (switch SW2 is on), in step S112 the pad 11 is
1 to the retracted position, and the process proceeds to step S113. If the pad 11 is in the retracted position, the process directly advances to step S113.

[0023] In step S113, release switch SW
5 is determined to be off, the process returns to step S101, and if it is determined to be on, the process proceeds to step S114. Step S1
In Step 14, the shutter 9 is driven to take a photograph, and then in Step S115, the film 22 is wound up by one frame, and the process returns to Step S101.

On the other hand, in step S201, the temperature sensor 45
If the detected temperature X is determined to be equal to or higher than the predetermined value X1,
The process advances to step S202 in FIG. In step S202, the LED 44 is turned off, and then in step S203, it is determined whether the switch SW1 is on. If the switch SW1 is off, it is determined that the pad 11 is in the retracted position and the process proceeds to step S113, and if the switch SW1 is on, it is determined that the pad 11 is in the protruding position and the pad 11 is driven to the retracted position. The process advances to step S112.

According to the above procedure, if the temperature X around the camera is less than the predetermined value X1 when setting the trimming shooting mode, the pad 11 is switched to the protruding position after shooting, and the trimming information is recorded by the magnetic head 10. Ru. In addition, when the temperature X around the camera is higher than the predetermined value X1 (when there is a risk that erroneous information may be recorded by the magnetic head 10), the pad 11 is forcibly switched to the retracted position and held, and at this time, the pad 11 is forcibly switched to the retracted position. Even when the switch 43 is turned on, the LED 44 does not light up and operation of the magnetic head 10, that is, cropping photography is prohibited. Therefore, erroneous trimming information is not recorded in a high-temperature environment, and undesirable photographs are prevented.

In the configuration of the above embodiment, the winding motor M2 constitutes the film feeding means 102, and the temperature sensor 45, the control circuit 51, the motor M1, the cam 33, and the spring 32 constitute the switching control means 105.

In the above example, the pad 11 is switched to the protruding position only when advancing the film frame, that is, when recording trimming information. If so, the pad 11 may be always held at the protruding position when the trimming photographing mode is set and the temperature X is less than a predetermined value.

Although the case where the trimming information is magnetically recorded on the film has been described above, another embodiment in which the photographed information is recorded in place of the trimming information will be described below. The photographed information is information indicating that the photographing of the frame has been completed, and this information is necessary when a partially photographed film is rewound and then used again. In other words, when you reload the film, you can read the shot information while winding the film, and stop winding when a frame for which shot information is not recorded is detected. Photographing can be restarted from the frame, and waste of film due to multiple exposure of photographed frames and excessive winding is prevented.

The flowchart in FIG. 8 shows the control procedure in this embodiment, and steps similar to those in FIG. 6 described above are given the same reference numerals. In FIG. 8, when it is determined in step S101 that the main switch 41 is turned on, the process proceeds to step S201 in the same way as described above, and it is determined whether the temperature X around the camera detected by the temperature sensor 45 is equal to or higher than a predetermined value X1, If it is determined that it is less than the predetermined value X1, the process advances to step S103. If it is determined that the release switch SW5 is off in step S103, the process returns to step S101, and if it is determined that the release switch SW5 is on, the process returns to step S106 to
The process of S108 is performed, and then, in step S301, photographed information for the frame is recorded. Thereafter, when winding of one frame is completed, the winding motor M2 is stopped in step S110, and the process returns to step S101.

On the other hand, if it is determined in step S201 that the temperature Step S30
Proceed to step 4. If it is determined that the switch SW1 is on, that is, if it is determined that the pad 11 is in the protruding position, the pad 11 is driven to the retracted position in step S303, and the process proceeds to step S304. In step S304, shutter release is prohibited, and then the process returns to step S101.

According to the above procedure, the temperature around the camera
When is greater than or equal to the predetermined value X1, the pad 11 is forcibly held in the retracted position, and photographing is prohibited even if the release button is operated at this time. Then, when the temperature X becomes less than a predetermined value X1, photographing is performed in response to the operation of the release button, and thereafter, the photographed information is recorded by the magnetic head 10 along with advancing the frame of the film. Therefore, erroneous photographed information is not recorded in a high-temperature environment, and multiple exposures and waste of film are prevented when the film is rewound and used again.

FIG. 9 shows a modification of the pad driving mechanism, in which the same parts as in FIG. 4 are given the same reference numerals. In this example, instead of the motor M1 and the cam 33 mentioned above,
A wire 61 made of a shape memory alloy (hereinafter referred to as shape memory wire) is used as an actuator. This shape memory wire 61 has one end fixed to a part of the camera body 1,
The other end is fixed to the rear end of the pad 11. Lead wires 62a connected to both ends of the shape memory wire 61,
When the wire 62b is energized, the wire 61 contracts, thereby driving the pad 11 to the retracted position shown in FIG. 9(b) against the biasing force of the spring 32. Further, when the power to the lead wires 62a and 62b is cut off, the shape memory wire 61
The pad 11 is extended to its original state by the biasing force of the spring 32, and the pad 11 is driven to the protruding position shown in FIG. 9(a).

Further, if a shape memory wire 61 having a property of shrinking in a high temperature environment exceeding a predetermined value is used, a temperature sensor is not required. That is, when the environmental temperature reaches a predetermined value or higher and the shape memory wire 61 contracts in the state shown in FIG. 9(a), the pad 11 is driven to the retracted position and the switch SW1 is turned off from on. Then, recording is not performed when the switch SW1 is off.

Here, as mentioned above, there is a risk of recording erroneous information due to performance deterioration of the magnetic head 10 even in an environment where the humidity is above a predetermined humidity, so a humidity sensor is used in place of the above-mentioned temperature sensor. Under the environment, the pad 11 is switched to the protruding position before the magnetic head 10 is operated, and when the humidity is above a predetermined humidity, the pad 11 is switched to the retracted position and held, thereby preventing erroneous information from being recorded. It's okay.

It is also possible that the positional relationship between the magnetic head and the pad is opposite to each other (the magnetic head is on the front side of the camera and the pad is on the rear side). In this case, the pad is fixed and the magnetic head is moved to the above-mentioned protruding position. and a retracted position, and in an environment below a predetermined temperature (humidity), the pad 11 is switched to the protruding position before operating the magnetic head 10, and in an environment above a predetermined temperature (humidity), the pad 11 is switched to the protruding position. What is necessary is to switch and hold it in the retracted position. Furthermore, the position of the magnetic recording area 22a is not limited to the lower part of the film 22, and may be provided, for example, at the upper part of the film 22.

[0036]

According to the invention as claimed in claim 1, the pad is switched to the protruding position before the magnetic head is operated in an environment below a predetermined temperature, and the pad is switched to the retracted position and held in an environment above a predetermined temperature. This prevents the magnetic head from being pressed against the film in a high-temperature environment where the performance of the magnetic head may deteriorate or the magnetic head may adhere to the film, thereby preventing erroneous information from being recorded. According to the second aspect of the invention, the magnetic head is switched to the protruding position before operating the magnetic head in an environment where the temperature is lower than a predetermined temperature, and the magnetic head is switched to the retracted position and held in an environment where the temperature is higher than the predetermined temperature. , the same effect as described above can be obtained. Furthermore, according to the invention of claim 3, in an environment where the humidity is less than a predetermined humidity, the pad is switched to the protruding position prior to the operation of the magnetic head, and in an environment where the humidity is higher than the predetermined humidity, the pad is switched to the retracted position and held. So,
It is possible to prevent incorrect information from being recorded in a high humidity environment. Furthermore, according to the invention of claim 4, the magnetic head is switched to the protruding position before operating the magnetic head in an environment with less than a predetermined humidity, and the magnetic head is switched to the retracted position in an environment with a predetermined humidity or higher. Since it is held, the same effect as described above can be obtained.

[Brief explanation of drawings]

FIG. 1 is a complaint correspondence diagram.

FIG. 2 is a perspective view of a camera according to an embodiment of the present invention, seen from the rear.

FIG. 3 is a side sectional view of the camera.

FIG. 4 is a diagram showing an example of a pad driving mechanism.

FIG. 5 is a block diagram of a control system.

FIG. 6 is a flowchart of a processing procedure.

FIG. 7 is a flowchart following FIG. 6;

FIG. 8 is a flowchart showing another embodiment.

FIG. 9 is a diagram showing a modification of the pad driving mechanism.

[Explanation of symbols]

1 Camera body 8 Photography lens 9 Lens shutter 10 Magnetic head 11 Pad 22 Film 22a Magnetic recording area 32 Spring 33 Cam 41 Main switch 42 Release button 43 Trimming switch 44 LED 45 Temperature sensor 51 Control circuit 52 Motor drive circuit 61 Shape memory wire 101 Film 102 Film feeding means 103,203 Magnetic head 104,204 Pad 105, 205 Switching control means M1 motor M2 Hoisting motor

Claims (4)

[Claims] 1. A film feeding means for feeding the film frame after shooting, a magnetic head for recording information in a magnetic recording area provided on the film as the film is fed frame by frame, and a magnetic head for recording information in a magnetic recording area provided on the film; The pad is switchable between a protruding position for pressing the magnetic recording area of the film against the magnetic head and a retracted position for retracting it from the film. What is claimed is: 1. A camera having a magnetic head, comprising switching control means for switching the pad to the protruding position and switching and holding the pad to the retracted position in an environment of a predetermined temperature or higher. 2. A film feeding means for feeding the film frame after photographing, a protruding position in which the film is brought into contact with a magnetic recording area provided on the film, and a retracted position in which the film is retracted from the magnetic recording area. , a magnetic head that records information in the magnetic recording area as the film frame is fed when the film is in the protruding position; a pad that presses the magnetic recording area of the film against the magnetic head; and an environment below a predetermined temperature. The magnetic head is characterized by comprising switching control means that switches the magnetic head to the protruding position prior to operation of the magnetic head, and switches and maintains the magnetic head in the retracted position in an environment of a predetermined temperature or higher. A camera with a magnetic head. 3. A film feeding means for feeding the film frame after shooting, a magnetic head for recording information in a magnetic recording area provided on the film as the film is fed frame by frame, and a magnetic head for recording information in a magnetic recording area provided on the film; The pad is switchable between a protruding position for pressing the magnetic recording area of the film against the magnetic head and a retracted position for retracting it from the film. What is claimed is: 1. A camera having a magnetic head, comprising switching control means for switching the pad to the protruding position and switching and holding the pad to the retracted position in an environment of a predetermined humidity or higher. 4. A film feeding means for feeding the film frame after photographing, a protruding position in which the film is brought into contact with a magnetic recording area provided on the film, and a retracted position in which the film is retracted from the magnetic recording area. , a magnetic head that records information in the magnetic recording area as the film frame is fed when the film is in the protruding position; a pad that presses the magnetic recording area of the film against the magnetic head; and an environment of less than a predetermined humidity. The present invention is characterized by comprising switching control means that switches the magnetic head to the protruding position prior to operation of the magnetic head, and switches and maintains the magnetic head in the retracted position in an environment with a predetermined humidity or higher. A camera with a magnetic head.