JP6402640B2 - Shooting system - Google Patents

Description

  The present invention relates to a photographing system capable of following a celestial body that moves in a diurnal motion and photographing in a stationary state.

  If you know the latitude of the shooting position (observation position), the azimuth and elevation angle of the shooting optical axis, and the attitude of the camera (rotation position with respect to the shooting optical axis), you can calculate the movement trajectory due to the diurnal motion of the celestial body. Elevation sensor that detects the elevation angle of the camera and camera posture (rotation angle, tilt angle around the shooting optical axis, or shooting where the reference direction of the imaging surface of the image sensor (imaging sensor) is tilted with respect to the horizontal direction It is already known that long-time shooting can be performed while tracking a celestial object based on a movement locus calculated using each data obtained from a posture sensor that detects a rotational position with respect to the optical axis (Patent Document 1). . Here, the orientation of the camera means a rotation angle and inclination around the optical axis, or an inclination of the reference direction of the image pickup surface of the image sensor (image pickup sensor) with respect to the horizontal direction. In addition, the position of the celestial bodies seen from the earth is defined by two numerical values that indicate the coordinates of the celestial bodies, the ascension and declination, and if the observation date and time (latitude / longitude) are known, The direction and height (corresponding to the azimuth and elevation angle of the photographic optical axis) of the celestial body at that position on the date and time can be calculated.

  However, in the astronomical tracking shooting based on the movement trajectory data calculated using the detection values of the conventional GPS, azimuth sensor, elevation angle sensor, posture sensor, etc., if the detection accuracy of each sensor is poor, the tracking shooting accuracy is low. There was a problem of going down. In particular, since the electronic compass is strongly influenced by the calibration accuracy and the surrounding magnetic environment, the orientation accuracy is not good.

  On the other hand, if the celestial body to be photographed is determined in advance, the celestial body's celestial / red latitude and the latitude / longitude data of the photographing position of the celestial body (although the photographer needs skill to accurately capture the celestial body at the center of the imaging surface) Since the azimuth and the elevation angle can be accurately calculated, there is no problem even if the accuracy of the azimuth data by the azimuth sensor and the elevation angle data by the elevation angle sensor is low or without these sensors. However, since the attitude data of the camera cannot be calculated, an attitude sensor is necessary, and there still remains a problem due to the accuracy of the attitude sensor. Also, the posture sensor has a problem that the posture (rotational angle around the optical axis) cannot be detected when the photographing optical axis is directed in the zenith direction (when the elevation angle is approximately 90 degrees). Even if the movement trajectory of the celestial body is obtained with high accuracy by calculation, the problem that the accuracy of tracking shooting is low cannot be solved if the posture detection accuracy of the camera is low.

  Patent Document 2 discloses an invention relating to astronomical tracking photography, which is obtained by performing preliminary photography in a state in which an imaging device and an image sensor are fixed without using each sensor such as a GPS, a direction sensor, an elevation sensor, and an attitude sensor. The moving direction and speed (rotation amount) of the celestial image are calculated from the moving locus image of the celestial image (subject image), and the image sensor is moved so as to cancel the moving direction and speed (rotation amount). Astronomical tracking photography that performs photography is disclosed.

  However, the calculation of the trajectory for tracking the celestial body according to Patent Document 2 requires all of the moving direction, speed, and rotation amount from the celestial image obtained by preliminary shooting, and therefore requires two or more celestial images to be recognized. The calculation amount was also complicated. In addition, there may be a case where sufficient accuracy cannot be obtained unless preliminary shooting is performed over an exposure time comparable to the exposure time for actually performing astronomical tracking shooting.

WO2011 / 136251 Publication JP 2012-5112 A

  An object of the present invention is to obtain an imaging system capable of subject tracking shooting with high accuracy.

The present inventor has found that sensor data with low accuracy can be complemented (corrected) from movement data of a subject moving along a known locus, and has completed the present invention.
That is, the present invention is an imaging system capable of determining the rotational position of the imaging device with respect to the imaging optical axis, and an object whose relative movement relationship with the imaging device can be defined by a physical law is determined from the object image captured by the imaging device. A relative movement direction detecting means for detecting a relative movement direction with respect to the photographing apparatus; a relative movement direction calculating means for calculating a relative movement direction of the object with respect to the photographing apparatus based on a relative movement relationship with respect to the photographing apparatus based on a physical law of the object; A rotational position for determining a rotational position of the photographing apparatus relative to the photographing optical axis based on a difference between the detected relative moving direction detected by the relative moving direction detecting means and the calculated relative moving direction calculated by the relative moving direction calculating means. And a discriminating means.

  The object in which the relative movement relationship can be defined by a physical law is a celestial body, and the relative movement direction calculation means calculates the calculated relative movement direction based on the focal length of the photographing optical system of the photographing apparatus and the celestial body. Can be calculated from the longitude and latitude, the latitude and longitude of the shooting point, and the date and time at the time of shooting.

  When the object whose relative movement relationship can be defined by a physical law is an astronomical object, the relative movement direction calculating means determines the calculated relative movement direction based on the focal length of the imaging optical system of the imaging apparatus and the elevation angle of the imaging optical axis. And the azimuth and the latitude of the shooting point.

  In the imaging system of the present invention, the object image formed on the imaging surface of the imaging device is imaged at least at the initial position on the imaging surface and when a set time has elapsed, and the relative movement is performed. The direction detecting means can detect the detected relative movement direction from an initial position on the imaging surface of the photographed object image and a position when a set time has elapsed.

  In the photographing system of the present invention, the object image is continuously exposed and photographed for a set time from at least the initial position, and the relative movement direction detecting means detects the detected relative movement direction based on the photographed object image. Can be detected from the initial position and the trajectory of the object image captured by continuous exposure.

  In the imaging system of the present invention, the object whose relative movement relationship can be defined by a physical law is an astronomical object, and the above-mentioned at a predetermined date and time is based on the determined rotational position around the imaging optical axis of the imaging apparatus. Relative movement trajectory data of the celestial body with respect to the imaging device is calculated, and based on the calculated relative movement trajectory data, the relative position between the imaging surface of the imaging device and the celestial image is fixed during a predetermined exposure time. It is practical to track and track the diurnal motion of celestial bodies.

  According to the present invention, since the movement trajectory of the subject image with respect to the imaging surface can be calculated with high accuracy, the moving subject can be tracked and photographed as a still image with high accuracy.

It is a block diagram which shows the principal part structure of the digital camera by this invention. It is a figure which shows the outline | summary of the imaging | photography operation | movement of the digital camera by this invention with a flowchart. It is a figure which shows the main operation | movement of 1st Embodiment of the attitude | position detection imaging | photography and attitude | position calculation operation | movement of a digital camera by this invention with a flowchart. It is a figure which shows the example of the image which carried out attitude | position detection imaging | photography with the digital camera by this invention. It is a figure which shows the main operation | movement of 2nd Embodiment of the attitude | position detection imaging | photography and attitude | position calculation operation | movement of a digital camera by this invention with a flowchart. It is a figure which shows the example of the image which carried out attitude | position detection imaging | photography with the digital camera by this invention. It is a figure which shows the outline | summary of the attitude | position detection imaging | photography of the digital camera by this invention, attitude | position calculation, and astronomical tracking imaging | photography operation | movement with a flowchart. It is a figure which shows the outline | summary of another aspect of the attitude | position detection imaging | photography of a digital camera by this invention, attitude | position calculation, and astronomical tracking imaging | photography operation | movement with a flowchart.

  The photographing apparatus of the present invention will be described with reference to FIGS. As shown in FIG. 1, a digital camera system 10 to which the photographing system of the present invention is applied includes a camera body 11 and a photographing lens 101 (photographing optical system L). In the camera body 11, an image sensor (imaging sensor, imaging element) 13 is disposed behind the imaging optical system L as imaging means. The optical axis (imaging optical axis) Z of the imaging optical system L and the imaging surface 14 of the image sensor 13 are orthogonal to each other. The image sensor 13 is mounted on a moving member drive unit (moving means) 15. The moving member drive unit 15 includes a fixed stage (not shown), a movable stage movable relative to the fixed stage, and an electromagnetic circuit that moves the movable stage relative to the fixed stage. 13 is held. The image sensor 13 (movable stage) is controlled to move in a desired direction orthogonal to the optical axis Z at a desired speed, and further, the optical axis Z or an axis parallel to the optical axis Z (in-plane orthogonal to the optical axis Z). Rotation is controlled at a desired rotational speed with the instantaneous center located somewhere in between. As the moving member drive unit 15, for example, a vibration isolation unit described in Patent Document 1 or 2 can be used.

  The photographing lens 101 includes a variable diaphragm 103 in the photographing optical system L. The aperture value (opening / closing degree) of the variable aperture 103 is controlled by the aperture drive control mechanism 17 provided in the camera body 11. Although not shown, the photographing optical system L includes a focus adjustment mechanism that can focus from infinity to a short distance.

  The camera body 11 is equipped with a CPU 21 that controls the functions of the entire camera. The CPU 21 controls the image sensor 13 to drive the image sensor, processes the captured image signal, displays it on the LCD monitor 23, and writes it in the memory card 25. The imaging drive control of the image sensor 13 by the CPU 21 includes setting of a frame rate for live view shooting and the like, and an image size and ISO sensitivity for still image shooting (recording). The camera body 11 includes an X-direction gyro sensor GSX, a Y-direction gyro sensor GSY, and a rotation detection gyro sensor GSR that detect shake applied to the camera body 11, and the CPU 21 drives the moving member drive unit 15 to reduce image shake. When using as a vibration isolation unit, the focal length f data is input from the focal length detection device 105 of the photographing lens 101, and the shake detection signal is input from the X direction gyro sensor GSX, the Y direction gyro sensor GSY, and the rotation detection gyro sensor GSR. Is done.

  The camera body 11 includes a power switch 27, a release switch 28, an astronomical photographing switch 29, and a setting switch 30 as switches. The CPU 21 executes control according to the on / off state of these switches 27, 28, 29, 30. For example, in response to an operation of the power switch 27, power supply from a battery (not shown) is turned on / off, and in response to an operation of the release switch 28, a focus adjustment operation, a photometry operation, and an imaging operation (astrophe tracking imaging operation) are executed. . The astronomical photographing switch 29 is a switch that causes the digital camera system 10 to start an astronomical tracking photographing operation in the astronomical tracking photographing mode. The setting switch 30 selects, for example, one of the celestial tracking shooting mode and the normal shooting mode for performing celestial tracking shooting, or data necessary for celestial tracking shooting mode (latitude, longitude, altitude of the shooting point). This is a switch for selecting a posture detection mode for inputting an astronomical object, an astronomical object, a declination data, and the like, and setting an ISO sensitivity.

Astronomical tracking shooting by the digital camera system 10 is performed by moving the image sensor 13 in accordance with the diurnal motion of the celestial body by the moving member drive unit 15 so that the celestial image on the imaging surface 14 of the image sensor 13 does not move on the imaging surface 14. While shooting.
The attitude of the digital camera system 10 means a rotational position rotated around the photographing optical axis Z of the digital camera system 10 (rotated from a certain reference attitude). More specifically, the longitudinal direction of the image sensor 13 at the initial position is set as a predetermined direction, the angle when the longitudinal direction is horizontal (horizontal plane) is defined as the reference posture when the longitudinal direction is horizontal, and the camera posture angle. This is the rotational position with respect to the photographing optical axis Z. The posture detection mode is a mode related to an operation of detecting a rotational position (camera posture angle) with respect to the photographing optical axis Z of the digital camera system 10.

  FIG. 2 is a flowchart regarding the posture detection operation for astronomical tracking photography. The photographer wears the digital camera system 10 on a tripod or the like and points to the celestial object to be imaged. At a certain moment, the image of the celestial object is approximately the center of the viewfinder field or approximately the center of the LCD monitor 23 in the so-called live view mode. In other words, it is assumed that there is a skill to adjust the composition so that it is positioned substantially in the center of the imaging surface 14 (so that the celestial body to be imaged coincides with the extended line of the imaging optical axis). The following embodiments operate under the overall control of the CPU 21.

  The digital camera system 10 (CPU 21) checks whether or not the power switch 27 is turned on (S101). If the power switch 27 is not turned on (S101: NO), this process is finished (end). Then, after waiting for a certain period of time to elapse, when the certain period of time has elapsed, this flowchart is entered to check the state of the power switch 27 (S101). When the power switch 27 is turned on (S101: YES), it is checked whether or not the posture detection mode is set (S102). When the posture detection mode is set (S102: YES), the posture detection in steps S103 to S106 is performed. Perform processing operations. The posture detection mode is a mode in which the inclination (rotation position, camera posture angle) around the optical axis Z of the bottom side of the digital camera system 10 or the longitudinal side of the imaging surface 14 is detected with reference to the horizontal direction.

  In step S103, the photographer or the like inputs the latitude / longitude of the current position, altitude that can be ignored, altitude, and the values of the longitude and latitude of the celestial object that is to be photographed (taken at the center of the field of view) It waits for (or confirmation if input is completed) (S103). The latitude / longitude and altitude of the current position can be easily checked using, for example, an Internet map website. Further, as in Patent Document 1, it is also possible to detect by GPS. As an input method, an input screen is displayed on the LCD monitor 23, and a photographer manually inputs (manual input) using a switch or the like (not shown), or a mobile phone connected to the digital camera system 10 by wire or wirelessly. There is a method of performing communication input from a terminal, a GPS terminal, or the like. The ascension and declination of the celestial object to be photographed can also be input from a portable terminal or the like connected to the digital camera system 10 by wire or wirelessly.

  Although not displayed in the flowchart, before or after step S103, the photographer sets the exposure time for exposure detection (shutter speed) and the shooting interval (set time Δt). The photographer may input appropriate values for the exposure time and the photographing interval, or the digital camera system 10 may automatically set appropriate values using the focal length f data of the photographing lens 101 or the like. Also good. In any case, this shooting interval (set time Δt) only needs to be able to detect the attitude of the digital camera system 10, so the preliminary shooting time in paragraph 0024 of “Patent Document 2” (“the diurnal motion trajectory of the astronomical object is calculated from the shooting results”). It ’s much shorter than what you can do ”).

  In addition, the photographer is in the approximate center of the finder field of view, or in the so-called live view mode, the approximate center of the LCD monitor 23, that is, approximately the center of the imaging surface 14 when the astronomical object to which data such as ascension and declination is input as an object to be imaged. The composition is adjusted so that it is positioned and fixed, and then the release switch 28 is turned on. The order of data input and composition adjustment does not matter.

  The digital camera system 10 (CPU 21) checks whether or not the release switch 28 is turned on when latitude / longitude and red / longitude data are inputted (or confirmed if already inputted) (S103: YES). If it is not turned on (S104: NO), the process returns to step S101. If it is turned on (S104: YES), each inputted data (latitude / longitude, red longitude / red latitude, posture detection photographing) Exposure time and shooting interval (set time Δt) are set (S105), posture detection shooting and posture calculation are executed (S106), an actual camera posture angle δ is obtained, and the process returns to step S101.

  When the digital camera system 10 (CPU 21) determines that it is not the posture detection mode in step S102 (S102: NO), it checks whether or not the release switch 28 is on (S107). If the release switch 28 is not turned on, the process returns to step S101 (S107: NO), and if the release switch 28 is turned on (S107: YES), shooting data such as exposure time, aperture, ISO sensitivity, etc. for normal shooting are obtained. The normal shooting operation is executed with the setting (S108), and the process returns to step S101 (S109, S101).

  FIG. 3 is a flowchart of the first embodiment regarding the posture detection photographing and posture calculation operation executed in step S106. In posture detection shooting and posture calculation 1, first shooting 1 is executed with a set exposure time (set shutter speed) for posture detection shooting (S111). An image obtained by shooting 1 is shown in FIG. The set exposure time is desirably a length (time) at which the star to be photographed appears in a dot shape as in the star image Ob1 in FIG. 4A, and may be set in advance, and based on the photometric value. It may be set.

  When shooting 1 (exposure) ends, the camera waits for a set time Δt seconds (waits for the celestial body to move after a while) (S112), and executes the second shooting 2 with the set exposure time (set shutter speed) (S113). ). An image obtained by photographing 2 is shown in FIG. By shooting 2, the shooting target star shot in shooting 1 is shot as a star image Ob2. The set exposure times for shooting 1 and shooting 2 may be the same or different. The set time Δt may be much shorter than the assumed main shooting (celestial body tracking shooting) time. The time from the start of shooting 1 (exposure) to the start or end of shooting 2 (exposure) may be set to be the set time Δt.

  The input latitude / longitude / red longitude / declination and the start date / time (shooting time) of shooting 1 are acquired from the camera, and the star image Ob1 obtained by shooting 1 is from which direction on the image sensor 13 at the set time Δt. (Calculated relative movement direction (calculated movement direction β)) is calculated (S114). The calculated relative movement direction β is calculated as an angle with respect to an arbitrary virtual reference direction. In this embodiment, a direction (reference direction α on the imaging surface) parallel to the longitudinal direction of the image sensor 13 (imaging surface) is set as a virtual reference direction, and the calculated relative movement direction β is an angle with respect to the reference direction α on the imaging surface. calculate.

The movement direction moved on the imaging surface 14 from the star images Ob1 and Ob2 obtained in the imaging 1 and the imaging 2 is detected as a detected relative movement direction (measured movement direction) γ from the imaging surface reference direction α (S115) (S115) FIG. 4 (C)), from the calculated relative movement direction β and the detected relative movement direction γ obtained by the calculation,
α + γ-β = δ
Thus, the actual camera posture angle δ is obtained and returned (S116, RET).
Note that the reference direction α on the imaging surface is parallel to one coordinate axis of the orthogonal coordinate axes serving as a reference for the moving direction, the rotating direction, the moving locus, and the position (coordinate) when the image sensor 13 is moved and controlled. Preferably, in this embodiment, it is set parallel to the longitudinal direction of the image sensor 13 (imaging surface). That is, α = 0 (°).

  For the sake of simplicity, it is assumed that one star can be photographed as point-like star images Ob1 and Ob2 in photographing 1 in step S111 and photographing 2 in step S113 (see FIGS. 4A and 4B). Since the set time Δt seconds has passed between the shooting 1 and the shooting 2, the star image Ob1 at the initial position is shot as the star image Ob2 at the moved position after the setting time Δt seconds. The movement direction on the imaging surface 14 is detected as a detected relative movement direction γ with respect to the imaging surface reference direction α parallel to the longitudinal direction of the imaging surface 14 as shown in FIG.

  If the orientation of the digital camera system 10 is assumed to be horizontal (α = 0 °) on the imaging surface, the focal length f data obtained from the photographing lens 101 and the latitude of the given photographing position are assumed. The initial position on the imaging surface 14 is set as the initial coordinates (0, 0) from the longitude, the longitude and latitude of the star to be photographed, and the photographing time or the latitude, photographing azimuth, and elevation angle of the photographing position. It is possible to calculate where the star image Ob1 at the initial position moves after the set time Δt seconds based on the physical law. An example of the calculation method is described in Patent Document 2. If the position of the star image Ob2 after movement obtained by calculation is the post-movement coordinate (X, Y), the movement direction (calculated relative movement direction β) can be obtained from calculation such as arcTan (X / Y).

By comparing the calculated calculated relative movement direction β and the measured detected relative movement direction γ, the camera posture angle δ with respect to the reference direction α on the imaging surface is an expression:
δ = α + γ-β
It is possible to obtain by If the reference direction α on the imaging surface is set parallel to the longitudinal direction of the imaging surface 14, α = 0 and the camera posture angle δ = γ−β.

  When the photographing optical axis Z faces the zenith (that is, vertical), the conventional camera cannot detect the camera posture angle δ by the posture sensor, or the accuracy is extremely low even if the camera posture angle δ can be detected. According to the present invention, for example, the camera posture angle δ (posture data) can be accurately calculated (defined) based on the longitudinal direction of the image pickup surface 14 (reference direction α on the image pickup surface).

  Thereafter, the camera attitude angle δ is the focal length f of the photographing optical system, the ascension and declination of the celestial object (star), the latitude and longitude of the photographing point, the date and time at the time of photographing, or the focal length f of the photographing optical system. And the moving locus (moving direction and moving speed) of the celestial body (star) based on the elevation angle and azimuth of the digital camera system 10 and the latitude of the photographing point. The moving member drive unit 15 is driven by the movement locus thus calculated, and continuous exposure shooting (bulb exposure shooting) is performed for a set time, and astronomical tracking shooting is performed. The movement trajectory of the star image to be photographed can be calculated by the calculation method described in Patent Document 1, for example.

  As described above, according to the digital camera system 10 to which the present invention is applied, since the posture of the digital camera system 10 can be accurately detected with high accuracy by posture detection photographing and posture calculation, the tracking is accurately performed based on an accurate astronomical movement trajectory. You can shoot. Since posture detection shooting and posture calculation only need to be able to detect the detected relative movement direction γ with respect to the reference direction on the imaging surface, posture detection is performed rather than the conventional method of obtaining the movement trajectory (movement direction and movement speed) of the celestial object by preliminary shooting and calculation. The time required for shooting has been shortened, the calculation has been simplified, and the time required has been shortened.

  In this embodiment, for example, the celestial object / star declination data of the celestial object (star) to be photographed is known, and the celestial object photographed by the photographer is captured in the approximate center of the screen (the photographing optical axis Z is accurately directed to the celestial object to be photographed). However, it is particularly useful when there is no GPS, azimuth sensor, orientation sensor, or the like, or when the tracking shooting result based on these sensor data and the stationary state of the subject cannot be satisfied.

  Note that the present invention stops posture detection shooting and posture calculation operation once the camera posture angle δ is detected, and detects a change in composition from a tripod detection by a gyro sensor or an acceleration sensor, etc. If there is a composition change, the posture detection photographing and the posture calculation operation may be performed again, or the composition change angle may be calculated from the data of the gyro sensor. According to this embodiment, since no useless operation is performed, it is possible to contribute to power saving.

  In shooting 1 in step S111 and shooting 2 in step S113, it is desirable that stars (celestial bodies) appear as dots. This is because a star (celestial body) is detected from each image in step S115 (whether fully automatic, semi-automatic, or fully manual) and the moving direction on the imaging surface 14 is accurately calculated. The user may input and set shooting conditions such as exposure time, aperture, ISO sensitivity (gain), and the amount of movement on the imaging surface 14 and the size (diameter) of the star image may be the focus of the shooting lens to be used. Since it is determined by the distance f, it may be automatically set. Similarly, the set time Δt may be set by the user or automatically set based on the focal length f.

  In the above embodiment, the CPU 21 drives and controls the image sensor 13 in a direction different from the optical axis Z direction via the moving member drive unit 15 to relatively move the imaging surface 14 of the image sensor 13 and the subject image. Means. Further, the CPU 21 calculates the movement trajectory (calculated relative to the virtual reference direction of the subject image) of the subject image formed on the imaging surface 14 of the subject image sensor 13 moving along the known locus defined by the physical law. The relative movement direction calculation means for calculating the movement direction β and the calculation speed) and a subject moving along a known locus were photographed by exposure at a predetermined set time Δt interval or at a predetermined set time Δt. A relative movement direction detection unit that detects a movement direction in which the subject image has actually moved from the subject image as a detected relative movement direction γ with respect to a reference direction on the imaging surface set on the imaging surface; and a relative movement direction detection unit; Based on the difference between the detected relative movement direction γ detected and the calculated relative movement direction β calculated by the relative movement direction calculation means, with respect to a predetermined reference direction on the imaging surface 14 To tilt angle (rotation angle, and orientation) constitutes a rotational position determination means for determining (rotational position of the photographing device) [delta].

  In the present embodiment shown in FIG. 3 and FIG. 4, the exposure time (shutter speed) for shooting 1 and shooting 2 is such that stars appear as dots, but only one is a dot image and the other is a line image. It may be the setting and shooting method. 5 and 6, in posture detection shooting, one is taken as a point image and the other is taken as a line image, and the posture is detected based on the point image and the line image (posture calculation). A second embodiment is shown. In the second embodiment, posture detection imaging and posture calculation operations are performed under the overall control of the CPU 21.

  In posture detection shooting and posture calculation 2, first, shooting 1 is executed with a set exposure time (S121). When the short exposure of the shooting 1 is completed, the CPU 21 executes the shooting 2 (S123). Photographing 2 is long-time exposure (bulb exposure) in which exposure is continued for a set time Δt.

  The input latitude / longitude, ascension / declination and the start date / time of shooting 1 are acquired, and the camera posture angle of the digital camera system 10 is assumed to be the angle of the virtual reference direction α, and the star image Ob1 obtained by shooting 1 is there. Is calculated in a direction relative to the virtual reference direction α on the virtual image plane after a set time Δt, and a calculated relative movement direction β is obtained.

A detected relative movement direction γ in which the star image has moved with respect to the reference direction α on the imaging surface 14 of the imaging surface 14 is detected from the star images obtained in the shooting 1 and the shooting 2 (S115), and the calculated relative movement direction β and the detected relative movement are detected. From the moving direction γ,
δ = α + γ-β
Thus, the actual camera posture angle δ is obtained (S116), and the process returns (RET).

  5 and 6 show a second embodiment. In the second embodiment, the star image Ob1 is first photographed so as to have a dot shape, and then the star image Ob3 is photographed by bulb exposure so that the star image Ob3 has a linear shape. This order may be changed, and there is no problem as long as the relationship between the direction of movement is clear. In addition, when shooting in a line, continuous exposure shooting is performed for a set time Δt, and the ISO sensitivity and aperture value are adjusted so as not to overshoot at that time. In FIG. 6, the star image Ob3 is drawn in a straight line. However, the star image Ob3 is not limited to a straight line and may be an arcuate curve, but the direction (γ) connecting the star image Ob1 and the end point of the star image Ob3 is the same. If it can be detected, it does not depend on the trajectory shape on the way.

  The above embodiment is an example in which the posture detection photographing and the posture calculation operation are performed when the posture detection mode is set, but the astronomical tracking photographing operation and the normal photographing operation are not performed. FIGS. 7 and 8 show that when the astronomical tracking shooting mode is set, when there is no camera posture information, posture detection shooting and posture calculation operation are automatically performed, and then automatic (continuous) tracking of the celestial body is performed. 6 shows a flowchart of an embodiment to be performed. The following embodiments operate under the overall control of the CPU 21.

  In this embodiment, a photographer inputs the ascension / declination data of a celestial body (star) to be photographed, the photographing optical axis of the digital camera system 10 is directed to the celestial body, and the center of the imaging surface 14 (viewer field of view). Or, the setting such as composition is adjusted so that the celestial image is located at the center of the screen of the LCD monitor 23. Latitudinal / longitude data of shooting locations Celestial ascension / declination data and date / time data are input manually by the photographer, using the camera's built-in clock, GPS reception data, various information terminals (smartphones, etc.) You may enter.

  The CPU 21 checks whether or not the power switch 27 is turned on at a predetermined timing (S201). If the power switch 27 is not turned on (step S201: NO, end) is periodically repeated. When the switch 27 is turned on (S201: YES), it is checked whether or not the astronomical tracking shooting mode is set (S202), and when the astronomical tracking shooting mode is not selected (when the normal shooting mode is selected) ( (S202: YES), the normal shooting mode is set (S213), and if the release switch 28 is on (S214: YES), the normal shooting is set (S215), the normal shooting operation is performed (S216), and step S201. If the release switch 28 is not turned on (S214: NO), the process directly returns to step S201. .

  When the astronomical tracking shooting mode is selected (S202: YES), the CPU 21 sets the astronomical tracking shooting mode (S203), and the photographer sets the latitude / longitude of the current position, the altitude, and the shooting target (center of view). It waits for the input of the values of the ascension and declination of the celestial object (or confirmation if already input) (S204). These operations are the same as those described for step S103 in FIG. 2 and related operations.

  When latitude / longitude and ascension / declination data are inputted (or confirmed if already inputted) (S204: YES), the CPU 21 checks whether or not there is posture information of the camera (S205). If there is no camera posture information (or if there is a photographer's instruction not to use it) (S205: NO), it is checked whether or not the release switch 28 is on (S206). (S206: NO) returns to step S201.

  When the release switch 28 is on (S206: YES), the setting for posture detection shooting and the setting for tracking shooting are set (S208). The setting for posture detection shooting includes a set exposure time (set shutter speed), a setting time Δt, an aperture value and ISO sensitivity used in posture detection shooting and posture calculation 1 or 2, and an aperture for main shooting (celestial body tracking shooting). Includes exposure data such as value, exposure time, ISO sensitivity. In addition, “setting to leave the camera” to these data is also included. Then, the CPU 21 performs posture detection photographing and posture calculation by the posture detection photographing setting set in step S208 (S210), determines the rotational position of the digital camera system 10 with respect to the photographing optical axis Z, that is, sets the camera posture angle δ. Ask.

  Subsequently, the CPU 21 performs astronomical orbit calculation in accordance with the tracking shooting setting set in step S208 (S211). In the celestial orbit calculation, the focal length f of the photographing optical system L, the ascension and declination of the celestial object to be photographed, the latitude and longitude of the photographing point, the date / time data at the time of photographing, the posture detection photographing and the posture calculation were obtained. A movement locus (relative movement locus data) for moving the image sensor 13 is calculated using the camera attitude angle δ. Thus, the CPU 21 performs predetermined exposure while driving the image sensor 13 via the moving member drive unit 15 based on the relative movement locus data calculated with the tracking shooting setting set before the photographer operates the release switch 28. Astronomical tracking shooting is performed for time exposure (S212). That is, the digital camera system 10 captures images while tracking the diurnal motion of the celestial body so that the relative position between the imaging surface 14 of the image sensor 13 and the celestial image during a predetermined exposure time is fixed.

  When the CPU 21 determines in step S205 that there is already posture information (S205: YES), the CPU 21 checks whether or not the release switch 28 is turned on (S207), and if not (S209: NO), step S201. If it is turned on (S207: YES), the setting for tracking imaging that has already been input is performed (S209), astronomical orbit calculation (S211) and astronomical tracking imaging are performed (S212), and the process returns to step S201.

As described above, the digital camera system 10 detects the camera posture angle δ by detecting the celestial body to be photographed at the center of the finder field of view or the center of the imaging surface, and the detected relative movement direction obtained by posture detection photographing and posture calculation operation. Since the detection is performed based on γ and the calculated relative movement direction β obtained by calculation, it is possible to detect the camera posture (camera posture angle δ) with high accuracy regardless of the presence or absence of the posture sensor and the accuracy. As described above, the digital camera system 10 can perform highly accurate astronomical tracking photography.
In this embodiment, since the celestial body tracking shooting is performed following the posture detection shooting and the posture calculation even without the posture information, the celestial body set by the photographer can be easily shot as a highly accurate still image.

  In the above-described embodiment of the celestial automatic tracking shooting, the photographer inputs latitude / longitude and ascension / declination data in step S204. May be.

  FIG. 8 shows an embodiment in which shooting location / azimuth / elevation angle data is automatically input. The same processes as those in the embodiment of FIG. 7 are denoted by the same step S numbers, and description thereof is omitted.

  When the power switch 27 is turned on (S201: YES), the CPU 21 checks whether there is shooting location / azimuth and elevation data (S201-2). If there is no data (S201-2: NO), the normal shooting mode is set (S213) and the normal shooting operation is performed (S214: S215: YES, S216, S201). The shooting location / azimuth and elevation data may be manually input by the photographer, and the latitude / longitude data of the shooting location may be acquired from a built-in or wireless or wired GPS device. May be input by any of the means and methods already described. If there is shooting location / azimuth and elevation data data (S201-2: YES), it is checked whether or not the celestial body tracking shooting mode is set (S202). If the celestial body tracking shooting mode is set (S202: YES), the celestial body is checked. The tracking shooting mode is set (S203), and the astronomical tracking shooting operation after step S205 is executed.

  The camera posture angle can be detected from a tripod detection by a gyroscope or an acceleration sensor, and the posture detection shooting can be performed again if there is a composition change, or the composition change angle can be calculated from the gyro data. .

  In the above embodiment, the image sensor 13 is used as the “moving member” and the image sensor 13 is driven in the plane orthogonal to the optical axis. However, the present invention is not limited to this. For example, a lens (optical element) forming at least a part of the photographic optical system L is used as a “moving member”, and the optical axis orthogonal plane is obtained by a voice coil motor (drive mechanism) provided with the lens (optical element) in the photographic lens 101. It is also possible to drive in the same manner. Further, a mode in which the entire camera body 11 including the photographing lens 101 and the image sensor 13 is driven as a “moving member” is also possible. Alternatively, a mode in which both the image sensor 13 and the lens (optical element) forming at least a part of the photographing optical system L are “moving members” and these are driven in an optical axis orthogonal plane is also possible. In either aspect, the tracking imaging effect can be obtained by moving the imaging position of the subject image on the image sensor 13.

In the present embodiment, the shooting of a celestial body such as a celestial body (star) moving along a predetermined trajectory and trajectory according to the laws of physics when viewed from the earth has been described, but the present invention is a moving body moving along a known trajectory and trajectory. Thus, the present invention can be applied to tracking shooting of an object whose movement direction and speed (movement trajectory) can be obtained by calculation based on physical laws. For example, when considering moving objects such as trains and race cars that come in the same direction and speed each time, if the moving speed v is known, the tracking speed on the moving object sensor can be calculated by m × v from the imaging magnification m. The shooting magnification m may be acquired as lens data at any time, and the equation m = H / (d−HH−H)
(D: shooting distance, H: distance from the second main surface to the image surface, HH: distance between main surfaces)
If the shooting distance d is sufficiently larger than the focal length, m≈H / (d−H). The shooting distance d and the distance H from the second main surface to the image plane are used for camera shake correction, AF, AE, and the like in current digital cameras. Many. Therefore, the camera can be installed without worrying about the camera posture, and the tracking speed for the moving object and the camera posture information (rotation position with respect to the photographing optical axis of the photographing device) can be acquired automatically by the above method. Become.

10 Digital camera system (shooting device, shooting system)
11 Camera body 13 Image sensor (imaging device)
14 Imaging surface 15 Moving member drive unit (moving member drive mechanism)
17 Aperture drive control mechanism 21 CPU (relative movement direction detection means, relative movement direction calculation means, rotational position determination means)
23 LCD monitor 25 Memory card 27 Power switch 28 Release switch 29 Astronomical shooting switch 30 Setting switch 101 Shooting lens (shooting optical system)
103 Variable Aperture 105 Focal Length Detection Device L Shooting Optical System GSX X Direction Gyro Sensor GSY Y Direction Gyro Sensor GSR Rotation Detection Gyro Sensor

Claims (6)

An imaging system that can determine the rotational position of the imaging device relative to the imaging optical axis,
A relative movement direction detecting means for detecting a relative movement direction of the object relative to the photographing apparatus from an object image photographed by the photographing apparatus with respect to an object whose relative movement relationship with the photographing apparatus can be defined by a physical law
A relative movement direction calculating means for calculating a relative movement direction of the object with respect to the photographing apparatus based on a relative movement relationship with respect to the photographing apparatus based on the physical law of the object;
Rotational position determination for determining the rotational position of the imaging apparatus with respect to the imaging optical axis based on the difference between the detected relative movement direction detected by the relative movement direction detection means and the calculated relative movement direction calculated by the relative movement direction calculation means Means,
An imaging system characterized by comprising: The imaging system according to claim 1,
An object whose relative movement relationship can be defined by physical laws is a celestial body,
The relative movement direction calculation means calculates the calculated relative movement direction based on the focal length of the photographing optical system of the photographing apparatus, the ascension and declination of the celestial body, the latitude and longitude of the photographing point, and the date and time at the time of photographing. Shooting system. The imaging system according to claim 1,
An object whose relative movement relationship can be defined by physical laws is a celestial body,
The relative movement direction calculating means calculates the calculated relative movement direction based on a focal length of a photographing optical system of the photographing apparatus, an elevation angle and an azimuth of the photographing optical axis, and a latitude of a photographing point. The imaging system according to any one of claims 1 to 3, wherein the object image formed on the imaging surface of the imaging device is at least at an initial position on the imaging surface and when a set time has elapsed. Shoot,
The relative movement direction detecting means detects the detected relative movement direction from an initial position on the imaging surface of the photographed object image and a position when a set time has elapsed. The photographing system according to any one of claims 1 to 3, wherein the object image is continuously exposed and photographed for a set time from at least an initial position,
The relative movement direction detecting means detects the detected relative movement direction from an initial position of the photographed object image and a trajectory of the object image photographed by continuous exposure. The imaging system according to any one of claims 1 to 5, wherein the object whose relative movement relationship can be defined by a physical law is an astronomical object,
Based on the determined rotational position of the photographing apparatus around the photographing optical axis, relative movement locus data of the celestial body with respect to the photographing apparatus at a predetermined date and time is calculated, and predetermined exposure is performed based on the calculated relative movement locus data. An imaging system that tracks and captures the diurnal motion of a celestial body so that the relative position between the imaging surface of the imaging apparatus and the celestial image is fixed during the time.

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