Control method of equatorial telescope

Abstract

The invention relates to the technical field of astronomical photography, in particular to a control method of an equatorial telescope, which comprises the following steps of: firstly, inputting control parameters of the equatorial telescope through a human-computer interface of a main controller and storing the control parameters in the main controller; a star image, obtained by an image sensor in a polar axis mirror, near a sky pole is checked through a human-computer interface, coordinates of a target position to be aligned are input through the human-computer interface, and an azimuth motor and a pitching motor are started to move a target to the center of a picture, so that the operation on the polar axis is completed; and then the main controller controls the equatorial telescope and the camera to photograph according to set programs and parameters. The method has the advantages that the operation on the polar axis is simplified, the programmed control on the equatorial telescope and the camera is introduced, and the creation means of astronomical photography are enriched.

Description

Technical Field

[0001] This invention relates to the field of astrophotography technology, and more specifically to a control method for an equatorial mount. Background Technology

[0002] An equatorial mount is a device used in astronomical observation and astrophotography to counteract the effects of the Earth's rotation and prevent the trailing of celestial objects caused by long exposures. However, in time-lapse photography with terrestrial scenery, if an existing equatorial mount is used, the scenery will shift in the final image, affecting the shooting effect. In addition, using an equatorial mount requires adjusting the right ascension axis to be parallel to the celestial pole axis. Existing polar alignment methods require manual adjustment of the direction, which is cumbersome for photographers who frequently change camera positions. Summary of the Invention

[0003] To address the problems mentioned in the background art, the present invention proposes a control method for an equatorial mount, characterized by comprising the following steps: S1: Set the control program and parameters of the equatorial mount and store them in the main controller; S2: Point the polar mirror of the equatorial mount toward the celestial pole; S3: Images of celestial bodies near the celestial pole are acquired by an image sensor installed in the polar mirror; S4: Select the target coordinates (x, y) to be aligned in the screen displaying the star image; S5: Calculate the offset (x-x0, y-y0) of the target coordinates from the center of the screen (x0, y0); S6: The offset angle (α, β) is calculated from the offset (x-x0, y-y0), the image sensor resolution (w, h), and the field of view (fh, fv) of the polar axis lens. The formula is as follows: ; S7: Start the azimuth motor and pitch motor to rotate the offset angle (α,β) so that the target in the image sensor is located in the center of the image; S8: The main controller controls the right ascension axis motor of the equatorial mount and the camera shutter to take pictures according to the set program and parameters; Furthermore, in steps S1 and S8, the main controller is a module or device with a human-machine interface and memory, based on a microprocessor or central processing unit. Furthermore, in steps S3, S6 and S7, the image sensor is a gain-adjustable CMOS or CCD sensor module or imaging device, and the normal of the light-receiving surface of the image sensor is parallel to the right ascension axis. Furthermore, in steps S4, S5, and S7, the screen is a human-machine interface connected to the main controller. Furthermore, in step S7, the output shafts of the azimuth motor and the pitch motor are orthogonal to each other; Furthermore, in step S8, the right ascension axis motor is connected to an encoder or an angle sensor; Furthermore, in step S8, the output shaft of the right ascension axis motor is orthogonal to the output shaft of the pitch motor in step S5; Furthermore, in step S8, controlling the camera shutter is achieved via a shutter release cable or wireless control method that connects the main controller and the camera.

[0004] Compared with existing star field equatorial mounts, the advantages of this invention are: The start and stop times and operating speed of the equatorial mount can be set, and the camera's exposure start and end can be controlled via the shutter controller. During the exposure, the equatorial mount rotates to eliminate celestial trails, and in-situ information is obtained from the encoder or angle sensor on the right ascension axis. After the exposure, the equatorial mount returns to its original position to maintain the landscape's position in the camera's frame. When the preset interval is reached, the equatorial mount rotates again, and the camera exposure is controlled, thus completing the time-lapse photography with interval shooting. In shooting time-lapse photography of day-night transitions, the exposure time can be dynamically controlled according to different ambient light intensities to avoid overexposure and underexposure. Imaging parameters such as ISO and aperture can also be adjusted through the camera application software, making the creation of photographic works more flexible and rich. When adjusting the right ascension axis to be parallel to the celestial axis, the target to be aligned is selected through the human-machine interface, and then the two motors of the dual-axis gimbal are started to rotate, adjusting the right ascension axis of the equatorial mount to the predetermined angle, which is convenient and quick. Attached Figure Description The accompanying drawings, which constitute the basis of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention. Figure 1 This is a schematic diagram of the system structure of the present invention. Figure 1 middle: 1. Human-machine interface; 2. Main controller; 3. Azimuth motor; 4. Pitch motor; 5. Right ascension axis motor; 6. Polar axis mirror. Detailed Implementation First, set the equatorial mount's running speed, interval time, shutter exposure time, and other parameters through the display terminal and buttons of the parameter control device. Then, point the equatorial mount's polar axis mirror toward the celestial pole, select the celestial body to be aimed at or a point around the celestial body through the human-machine interface, start the dual-axis gimbal to move the target to the center of the image, and then control the equatorial mount to rotate and the camera to take pictures according to the set program.

[0005] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, any modifications, substitutions, improvements, etc., made without departing from the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for controlling an equatorial mount, characterized in that, Includes the following steps: S1: Set the control program and parameters of the equatorial mount and store them in the main controller; S2: Point the polar mirror of the equatorial mount toward the celestial pole; S3: Images of celestial bodies near the celestial pole are acquired by an image sensor installed in the polar mirror; S4: Select the target coordinates (x, y) to be aligned in the screen displaying the star image; S5: Calculate the offset (x-x0, y-y0) of the target coordinates from the center of the screen (x0, y0); S6: The offset angle (α, β) is calculated from the offset (x-x0, y-y0), the image sensor resolution (w, h), and the field of view (fh, fv) of the polar axis lens. The formula is as follows: ; S7: Start the azimuth motor and pitch motor to rotate the offset angle (α,β) so that the target in the image sensor is located in the center of the image; S8: The main controller controls the right ascension axis motor of the equatorial mount and the camera shutter to take pictures according to the set program and parameters.

2. The control method for a star field equatorial mount according to claim 1, characterized in that: In steps S1 and S8, the main controller is a module or device with a human-machine interface and memory, with a microprocessor or central processing unit as its core.

3. The control method for a star field equatorial mount according to claim 1, characterized in that: In steps S3, S6, and S7, the image sensor is a gain-adjustable CMOS or CCD sensor module or imaging device, and the normal of the light-receiving surface of the image sensor is parallel to the right ascension axis.

4. The control method for a star field equatorial mount according to claim 1, characterized in that: In steps S4, S5 and S7, the screen is the human-machine interface of the main controller.

5. The control method for a star field equatorial mount according to claim 3, characterized in that: In step S7, the output shafts of the azimuth motor and the pitch motor are orthogonal to each other.

6. The control method for a star field equatorial mount according to claim 1, characterized in that: In step S8, the right ascension axis motor is connected to an encoder or an angle sensor.

7. The control method for a star field equatorial mount according to claim 1, characterized in that: In step S8, the output shaft of the right ascension axis motor is orthogonal to the output shaft of the pitch motor in step S5.

8. The control method for a star field equatorial mount according to claim 1, characterized in that: In step S8, controlling the camera shutter is achieved by connecting the main controller and the camera via a shutter release cable or wireless control.

Images