Method of automatically tracking and photographing celestial objects, and celestial-object auto-tracking photographing apparatus

• US 9,310,459 B2
• Filed: 06/12/2012
• Issued: 04/12/2016
• Est. Priority Date: 06/16/2011
• Status: Active Grant

• Current Assignee: Ricoh Imaging Company Limited (Ricoh Company Limited)
• Original Assignee: Ricoh Imaging Company Limited (Ricoh Company Limited)
• Inventors: Ohta, Makoto
• Primary Examiner(s): Mehta, Bhavesh
• Assistant Examiner(s): Mistry, Oneal R
• Application Number:
  US14/125,667
• Publication Number:
  US 20140125816A1
• Time in Patent Office: 1,400 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: G01S 3/7864 T.V. type tracking systems
• CPC Class Codes: G02B 27/648 for automatically maintaining a reference alignment, e.g. in self-levelling surveying instruments surveying instruments per se G01C
• CPC Class Codes: G03B 15/00 Special procedures for taking photographs; Apparatus therefor
• CPC Class Codes: G03B 2205/0038 by displacing the image plane with respect to the optical axis in case of an electronic image sensor H04N23/68
• CPC Class Codes: H04N 23/6842 by controlling the scanning position, e.g. windowing
• CPC Class Codes: H04N 23/69 Control of means for changing angle of the field of view, e.g. optical zoom objectives or electronic zooming
• CPC Class Codes: H04N 25/443 by reading pixels from selected 2D regions of the array, e.g. for windowing or digital zooming

Abstract

Automatically tracking and photographing celestial objects and a celestial-object auto-tracking photographing apparatus, in which the burden on the CPU can be reduced by eliminating unnecessary arithmetic processes and can clearly photograph an object(s) so as to appear stationary without using an equatorial, and without using an actuator, which must be precisely controlled. The method includes moving relative to a photographic apparatus due to diurnal motion, to photograph a trimming area that has been electronically trimmed from a part of an imaging area of an image sensor, moving while the celestial object is photographed, including obtaining movement information of an image on the imaging area; setting movement data for the trimming area based on the obtained movement information of the image; and carrying out a photographing operation while moving the trimming area based on the movement data of the set trimming area at each trimming area, upon being moved.

Claims

1. A method of automatically tracking and photographing a celestial object, which moves relative to a photographic apparatus due to diurnal motion, in which, in order to photograph the celestial object, a trimming area that has been electronically trimmed from a part of an imaging area of an image sensor is moved while the celestial object is photographed, said method comprising:

obtaining movement information of a celestial-object image on said imaging area;

setting movement data for said trimming area based on the obtained said movement information of said celestial-object image;

setting a cut-out range of said trimming area and photographing time; and

obtaining a photographing image at each trimming area while moving said trimming area based on the set said movement data of said trimming area, said cut-out range of said trimming area, and said photographing time,

wherein the step of setting a cut-out range of said trimming area and photographing time includes;

cutting out a trimming area that is smaller than said imaging area from said imaging area of said image sensor;

calculating a maximum time in which said trimming area can be accommodated within said imaging area of said image sensor as a maximum photographing time, when the cut-out said trimming area is virtually moved based on said movement data of said trimming area; and

setting the calculated maximum photographing time as a photographing time.

2. The method of automatically tracking and photographing a celestial object according to claim 1, wherein said imaging area of said image sensor is rectangular in shape, and

wherein a rectangular trimming area which is parallel to the long sides and the short sides of said rectangular imaging area of said image sensor is cut out in said cutting out step of said trimming area.

3. The method of automatically tracking and photographing a celestial object according to claim 1, further comprising:

inputting focal length information of said photographing optical system of said photographing apparatus, latitude information of a photographic site, photographing azimuth angle information, photographing elevation angle information, and posture information of said photographing apparatus,

wherein in the step of obtaining said movement information, said movement information of said celestial object image in said trimming area is obtained by using said input information.

4. A method of automatically tracking and photographing a celestial object, which moves relative to a photographic apparatus due to diurnal motion, in which, in order to photograph the celestial object, a trimming area that has been electronically trimmed from a part of an imaging area of an image sensor is moved while the celestial object is photographed, said method comprising:

obtaining movement information of a celestial-object image on said imaging area;

setting movement data for said trimming area based on the obtained said movement information of said celestial-object image;

setting a cut-out range of said trimming area and photographing time; and

obtaining a photographing image at each trimming area while moving said trimming area based on the set said movement data of said trimming area, said cut-out range of said trimming area, and said photographing time,

wherein the step of setting a cut-out range of said trimming area and photographing time includes;

setting a desired photographing time;

calculating movement data of said imaging area of said image sensor based on the obtained said movement information of said celestial object image; and

cutting out said trimming area from a commonly used part of said imaging area of said image sensor when the imaging area of the image sensor is virtually moved based on the calculated movement data, of said imaging area, within the set said photographing time.

5. A method of automatically tracking and photographing a celestial object, which moves relative to a photographic apparatus due to diurnal motion, in which, in order to photograph the celestial object, a trimming area that has been electronically trimmed from a part of an imaging area of an image sensor is moved while the celestial object is photographed, said method comprising:

obtaining movement information of the celestial object image, said movement information including a movement direction, a movement distance and a rotational angle of said celestial object image in said trimming area;

setting movement data which includes a movement direction, a movement distance, a rotational angle and a movement period of said trimming area based on the obtained said movement information of said celestial-object image;

obtaining a photographing image of each trimming area, upon being moved, while moving said trimming area based on the movement data of the set said trimming area,

wherein in the step of obtaining said movement information, said movement distance of said celestial object image per said predetermined time period in said trimming area is obtained by dividing said movement distance into a linear movement component in a direction orthogonal to an optical axis of said photographing optical system, and a rotational movement component about an axis parallel to said photographing optical system, and

wherein in the step of setting said movement data, by setting the shortest movement period out of the movement period of the trimming area which corresponds to the movement distance of the obtained said linear movement component, and the movement period of the trimming area which corresponds to the movement distance of the obtained said rotational movement component as the movement period of said trimming area, said movement period of said trimming area is set so that the movement distance of said celestial object image per a predetermined time period in said trimming area is within a range so as not to exceed a pixel pitch of said trimming area.

6. The method of automatically tracking and photographing a celestial object according to claim 5, further comprising:

updating said movement period of said trimming area during the photographing time.

7. A celestial-object auto-tracking photographing apparatus, in which, in order to photograph a celestial object which moves relative to a photographic apparatus due to diurnal motion, a trimming area that has been electronically trimmed from a part of an imaging area of an image sensor is moved while the celestial object is photographed, said celestial-object auto-tracking photographing apparatus comprising:

an obtaining device which obtains movement information of a celestial-object image on said imaging area;

a first setter which sets movement data for said trimming area based on the obtained said movement information of said celestial-object image by said obtaining device;

a second setter which sets a cut-out range of said trimming area and photographing time; and

a photographing device which obtains a photographing image at each trimming area while moving said trimming area based on said movement data of said trimming area, said cut-out range of said trimming area, and said photographing time that have been set by the first and second setters,

wherein said second setter cuts out a trimming area that is smaller than said imaging area from said imaging area of said image sensor, calculates a maximum time in which said trimming area can be accommodated within said imaging area of said image sensor as a maximum photographing time, when the cut-out said trimming area is virtually moved based on said movement data of said trimming area, and sets the calculated maximum photographing time as a photographing time.

8. A celestial-object auto-tracking photographing apparatus, in which, in order to photograph the celestial object which moves relative to a photographic apparatus due to diurnal motion, a trimming area that has been electronically trimmed from a part of an imaging area of an image sensor is moved while the celestial object is photographed, said celestial-object auto-tracking photographing apparatus comprising:

an obtaining device which obtains movement information of a celestial-object image on said imaging area;

a first setter which sets movement data for said trimming area based on the obtained said movement information of said celestial-object image by said obtaining device;

a second setter which sets a cut-out range of said trimming area and photographing time; and

a photographing device which obtains a photographing image at each trimming area while moving said trimming area based on said movement data of said trimming area, said cut-out range of said trimming area, and said photographing time that have been set by the first and second setters,

wherein said second setter sets a desired photographing time, calculates movement data of said imaging area of said image sensor based on the obtained said movement information of said celestial object image, and cuts out said trimming area from a commonly used part of said imaging area of said image sensor when the imaging area of the image sensor is virtually moved based on the calculated movement data, of said imaging area, within the set said photographing time.

9. A celestial-object auto-tracking photographing apparatus, in which, in order to photograph the celestial object which moves relative to a photographic apparatus due to diurnal motion, a trimming area that has been electronically trimmed from a part of an imaging area of an image sensor is moved while the celestial object is photographed, said celestial-object auto-tracking photographing apparatus comprising:

an obtaining device which obtains movement information of a celestial-object image on said imaging area, said movement information including a movement direction, a movement distance and a rotational angle of said celestial object image in said trimming area;

a setter which sets movement data which includes a movement direction, a movement distance, a rotational angle and a movement period of said trimming area based on said movement information of said celestial-object image that is obtained by said obtaining device;

a photographing device which obtains a photographing image of each trimming area, upon being moved, while moving said trimming area based on the movement data of said trimming area that is set by said setter,

wherein said obtaining device obtains said movement distance of said celestial object image per said predetermined time period in said trimming area by dividing said movement distance into a linear movement component in a direction orthogonal to an optical axis of said photographing optical system, and a rotational movement component about an axis parallel to said photographing optical system, and

wherein said setter sets said movement period of said trimming area so that the movement distance of said celestial object image per a predetermined time period in said trimming area is within a range so as not to exceed a pixel pitch of said trimming area, by setting the shortest movement period out of the movement period of the trimming area which corresponds to the movement distance of the obtained said linear movement component, and the movement period of the trimming area which corresponds to the movement distance of the obtained said rotational movement component as the movement period of said trimming area.