Early photographic synchronization system and method

• US 8,917,350 B2
• Filed: 02/12/2010
• Issued: 12/23/2014
• Est. Priority Date: 02/12/2009
• Status: Active Grant

• Current Assignee: LAB Partners Associates Incorporated
• Original Assignee: Lab Patners Associates Incorporated
• Inventors: Clark, James E.
• Primary Examiner(s): Ho, Tuan
• Assistant Examiner(s): Nazrul, Shahbaz
• Application Number:
  US13/201,281
• Publication Number:
  US 20120127361A1
• Time in Patent Office: 1,775 Days
• Field of Search: 348/370, 348/371, 396/180, 396/179, 396/187, 396/188, 396/194, 396/195, 396/167, 396/186
• US Class Current: 348/371
• CPC Class Codes: G03B 15/05 Combinations of cameras with electronic flash apparatus; Electronic flash units
• CPC Class Codes: G03B 2215/05 Combinations of cameras with electronic flash units
• CPC Class Codes: G03B 9/40 Double plate

Abstract

A system and method for synchronizing a photographic lighting device to image acquisition by a camera such that initiation of light emission of the photographic lighting device occurs after the first shutter blade of the camera begins to expose an image acquisition sensor of the camera to light and before X-sync associated with the first shutter blade stopping movement.

Claims

1. A method for synchronizing a photographic lighting device to image acquisition by a camera, the method comprising:

detecting a predictor signal and/or event;

determining an amount of time from the occurrence of the predictor signal and/or event until a desired time for the initiation of light emission of the photographic lighting device;

transmitting to the photographic lighting device an instruction for the initiating light emission of the photographic lighting device at the desired time;

allowing a first shutter blade of the camera to move such that light is allowed to pass to an imaging portion of an image acquisition sensor of the camera; and

initiating light emission of the photographic lighting device, using the instruction, after the first shutter blade begins to expose the image acquisition sensor to light and before X-sync associated with the first shutter blade stopping movement,

where said determining an amount of time includes utilization of time value determined using a calibration that includes;

initiating an image acquisition sequence;

determining a start of movement of a second shutter blade; and

using a shutter speed of the image acquisition, a shutter blade travel time for the camera, and a time from the occurrence of the predictor signal and/or event to the start of movement of the second shutter blade to determine the time from the predictor signal and/or event to the stopping of movement of the first shutter blade.

2. A method according to claim 1, wherein the initiating light emission occurs such that an initial critical point of a flash profile of the photographic lighting device occurs at a point in time after about 1 millisecond before the first shutter blade moves to a position that no longer obstructs light to the imaging portion of the sensor.

3. A method according to claim 1, wherein the initiating light emission occurs such that an initial critical point of a flash profile of the photographic lighting device occurs at a point in time after about 500 microseconds before the first shutter blade moves to a position that no longer obstructs light to the imaging portion of the sensor.

4. A method according to claim 1, wherein the initiating light emission occurs such that an initial critical point of a flash profile of the photographic lighting device occurs at a point in time after about 250 microseconds before the first shutter blade moves to a position that no longer obstructs light to the imaging portion of the sensor.

5. A method according to claim 1, wherein the initiating light emission occurs such that an initial critical point of a flash profile of the photographic lighting device occurs at a point in time after the first shutter blade moves to a position that no longer obstructs light to the imaging portion of the sensor.

6. A method according to claim 1, wherein the initiating light emission occurs such that an initial critical point of a flash profile of the photographic lighting device occurs at about the time the first shutter blade moves to a position that no longer obstructs light to the imaging portion of the sensor.

7. A method according to claim 1, wherein the initiating light emission occurs such that an initial critical point of a flash profile of the photographic lighting device occurs before the first shutter blade stops movement.

8. A method according to claim 1, wherein the initiating light emission occurs such that a terminal critical point of a flash profile of the photographic lighting device occurs less than about 500 microseconds after a second shutter blade of the camera moves to a point where the second shutter blade starts to obstruct light from passing to the imaging portion of the sensor.

9. A method according to claim 1, wherein the initiating light emission occurs such that a terminal critical point of a flash profile of the photographic lighting device occurs less than about 250 microseconds after a second shutter blade of the camera moves to a point where the second shutter blade starts to obstruct light from passing to the imaging portion of the sensor.

10. A method according to claim 1, wherein the initiating light emission occurs such that a terminal critical point of a flash profile of the photographic lighting device occurs at about the time that the second shutter blade starts to obstruct light from passing to the sensor.

11. A method according to claim 1, wherein the initiating light emission occurs such that a terminal critical point of a flash profile of the photographic lighting device occurs before the time that the second shutter blade starts to obstruct light from passing to the sensor.

12. A method according to claim 1, wherein the predictor signal and/or event includes a camera predictor event and/or signal that occurs prior to the first shutter blade of the camera moving to a point that allows light to pass to the sensor, the predictor event and/or signal not being an event or signal for instructing the initiation of light emission from a photographic lighting device, the predictor event and/or signal occurring prior to a normal flash initiation event or signal intended to instruct the light emission of the photographic lighting device.

13. A method according to claim 1, wherein the predictor signal and/or event includes a camera predictor event and/or signal that is not an event or signal intended for instructing the initiation of an X-sync flash pulse and occurs prior to the time of X-sync.

14. A method according to claim 1, wherein the predictor signal and/or event is a serial data communication of the camera.

15. A method according to claim 14, wherein the serial data communication is a power set command.

16. A method according to claim 1, wherein the predictor signal and/or event is a drop in a voltage of a clock signal of the camera.

17. A method according to claim 1, wherein the predictor signal and/or event is the initiation of a shutter magnet release signal.

18. A method according to claim 1, wherein the predictor signal and/or event is the initiation of an FP-synch signal and the initiating light emission does not include an FP-type flash emission.

19. A method according to claim 1, wherein the transmitting to the photographic lighting device includes delivering the instruction internal to the camera to an internal lighting device.

20. A method according to claim 1, wherein the transmitting to the photographic lighting device includes delivering the instruction via a hot shoe connector of the camera to the photographic lighting device, the photographic lighting device being positioned in the hot shoe connector.

21. A method according to claim 1, wherein the transmitting to the photographic lighting device includes wirelessly transmitting the instruction to the photographic lighting device.

22. A method according to claim 21, wherein the wirelessly transmitting includes a radio frequency transmission.

23. A method according to claim 21, wherein the instruction is wirelessly transmitted prior to the first shutter blade moving to a position that no longer obstructs light to the imaging portion of the sensor.

24. A method according to claim 21, wherein the instruction is received by a wireless communications receiver associated with the photographic lighting device prior to the first shutter blade moving to a position that no longer obstructs light to the imaging portion of the sensor.

25. A method according to claim 21, wherein the instruction is wirelessly transmitted prior to the occurrence of the normal flash initiation event or signal.

26. A method according to claim 21, wherein the instruction is received by a wireless communications receiver associated with the photographic lighting device prior to the occurrence of the normal flash initiation event or signal.

27. A method according to claim 1, wherein the initiating light emission occurs at a time delayed from completion of the transmitting to the photographic lighting device the instruction.

28. A method according to claim 27, wherein the instruction includes a delay factor.

29. A method according to claim 27, wherein the instruction includes a precalculated time for the initiating light emission.

30. A method according to claim 1, wherein the identifying includes detecting the predictor event and/or signal external to the camera.

31. A method according to claim 30, wherein the detecting occurs via a hot shoe connector of the camera.

32. A method according to claim 1, wherein the detecting a predictor signal and/or event includes identifying the occurrence of an FP-sync signal of the camera.

33. A method according to claim 1, wherein the detecting a predictor signal and/or event includes identifying the occurrence of a drop in voltage of a clock signal of the camera, the drop in voltage occurring after triggering of image acquisition and prior to the first shutter blade stopping movement.

34. A method according to claim 1, wherein the using step of the calibration includes:

determining the time from the stopping of movement of the first shutter blade to the start of movement of the second shutter blade utilizing the shutter speed and the shutter blade travel time for the camera; and

determining the time from the predictor signal and/or event to the stopping of movement of the first shutter blade utilizing the time from the occurrence of the predictor signal and/or event to the start of movement of the second shutter blade and the time from the stopping of movement of the first shutter blade to the start of movement of the second shutter blade.

35. A method according to claim 1, wherein the determining an amount of time includes utilization of a second time value determined using a calibration that includes:

initiating an image acquisition sequence;

analyzing the resultant image; and

modifying an adjustment factor that impacts the value of a delay factor of the instruction.

36. A method for synchronizing a photographic lighting device to image acquisition by a camera, the method comprising:

detecting a predictor signal and/or event;

determining an amount of time from the occurrence of the predictor signal and/or event until a desired time for the imitiation of light emission of the photographic lighting device;

transmitting to the photographic lighting device an instruction for the initiating light emission of the photographic lighting device at the desired time;

allowing a first shutter blade of the camera to move such that light is allowed to pass to an image acquisition sensor of the camera; and

initiating light emission of the photographic lighting device, using the instruction, after the first shutter blade begins to expose the image acquisition sensor to light and before the shutter travel completion switch is detected by camera,

wherein said determining an amount of time includes utilization of a time value determined using a calibration that includes;

initiating an image acquisition sequence;

determining a start of movement of a second shutter blade; and

using a shutter speed of the image acquisition, a shutter blade travel time for the camera, and a time from the occurrence of the predictor signal and/or event to the start of movement of the second shutter blade to determine the time from the predictor signal and/or event to the stopping of movement of the first shutter blade.

49. A method according to claim 36, wherein the initiating light emission occurs such that an initial critical point of a flash profile of the photographic lighting device occurs at a point in time after about 1 millisecond before the first shutter blade moves to a position that no longer obstructs light to the imaging portion of the sensor.

50. A method according to claim 36, wherein the predictor signal and/or event includes a camera predictor event and/or signal that occurs prior to the first shutter blade of the camera moving to a point that allows light to pass to the sensor, the predictor event and/or signal not being an event or signal for instructing the initiation of light emission from a photographic lighting device, the predictor event and/or signal occurring prior to a normal flash initiation event or signal intended to instruct the light emission of the photographic lighting device.

51. A method according to claim 36, wherein the instruction is wirelessly received by a wireless communications receiver associated with the photographic lighting device prior to the occurrence of the normal flash initiation event or signal.

52. A method according to claim 36, wherein the detecting a predictor signal and/or event includes identifying the occurrence of an FP-sync signal of the camera.

53. A method according to claim 36, wherein the detecting a predictor signal and/or event includes identifying the occurrence of a drop in voltage of a clock signal of the camera, the drop in voltage occurring after triggering of image acquisition and prior to the first shutter blade stopping movement.

37. A system for synchronizing a photographic lighting device to image acquisition by a camera, the system comprising:

means for detecting a predictor signal and/or event;

means for determining an amount of time from the occurrence of the predictor signal and/or event until a desired time for the initiation of light emission of the photographic lighting device;

means for communicating to the photographic lighting device an instruction for the initiating light emission of the photographic lighting device at the desired time;

means for allowing a first shutter blade of the camera to move such that light is allowed to pass to an imaging portion of an image acquisition sensor of the camera; and

means for initiating light emission of the photographic lighting device, using the instruction, after the first shutter blade begins to expose the image acquisition sensor to light and before X-sync associated with the first shutter blade stopping movement,

wherein said means for determining an amount of time includes a means for utilization of a time value, the time value determined using a calibration that includes;

a means for initiating an image acquisition sequence;

a means for determining a start of movement of a second shutter blade; and

a means for using a shutter speed of the image acquisition, a shutter blade travel time for the camera, and a time from the occurrence of the predictor signal and/or event to the start of movement of the second shutter blade to determine the time from the predictor signal and/or event to the stopping of movement of the first shutter blade.

38. A system according to claim 37, wherein the means for initiating light emission is configured to have light emission initiation occur such that an initial critical point of a flash profile of the photographic lighting device occurs at a point in time after about 1 millisecond before the first shutter blade moves to a position that no longer obstructs light to the imaging portion of the sensor.

39. A system according to claim 37, wherein the predictor signal and/or event includes

a camera predictor event and/or signal that occurs prior to the first shutter blade of the camera moving to a point that allows light to pass to the sensor, the predictor event and/or signal not being an event or signal for instructing the initiation of light emission from a photographic lighting device, the predictor event and/or signal occurring prior to a normal flash initiation event or signal intended to instruct the light emission of the photographic lighting device.

40. A system according to claim 39, wherein the means for detecting a predictor signal and/or event includes means for identifying a camera predictor event and/or signal that is not an event or signal intended for instructing the initiation of an X-sync flash pulse and occurs prior to the time of X-sync.

41. A system according to claim 37, wherein the means for communicating includes means for delivering the instruction internal to the camera to an internal lighting device.

42. A system according to claim 37, wherein the means for communicating includes means for delivering the instruction via a hot shoe connector of the camera to the photographic lighting device, the photographic lighting device being positioned in the hot shoe connector.

43. A system according to claim 37, wherein the means for communicating includes means for wirelessly transmitting the instruction to the photographic lighting device.

44. A system according to claim 37, wherein the means for detecting includes means for detecting the predictor signal and/or event external to the camera.

45. A system according to claim 44, wherein the means for detecting includes a hot shoe connector of the camera.

46. A system according to claim 37, wherein the using a shutter speed of the image acquisition, a shutter blade travel time for the camera, and a time from the occurrence of the predictor signal and/or event to the start of movement of the second shutter blade includes:

determining the time from the stopping of movement of the first shutter blade to the start of movement of the second shutter blade utilizing the shutter speed and the shutter blade travel time for the camera; and

determining the time from the predictor signal and/or event to the stopping of movement of the first shutter blade utilizing the time from the occurrence of the predictor signal and/or event to the start of movement of the second shutter blade and the time from the stopping of movement of the first shutter blade to the start of movement of the second shutter blade.

47. A system according to claim 37, wherein the means for determining an amount of time includes utilization of a second time value determined using a calibration that includes:

initiating an image acquisition sequence;

analyzing the resultant image; and

modifying an adjustment factor that impacts the value of a delay factor of the instruction.

48. A system for synchronizing a photographic lighting device to image acquisition by a camera having an image acquisition sensor and a shutter system with a first shutter blade, the system comprising:

a connection to a camera circuitry providing access to a camera predictor signal;

a memory including information related to instructions for initiating light emission after the first shutter blade begins to expose the image acquisition sensor to light and before X-sync associated with the first shutter blade stopping movement;

a processor element configured to use the information, the camera predictor signal, and a time value to generate a lighting emission initiation signal, the time value determined using a calibration that includes;

initiating an image acquisition sequence;

determining a start of movement of a second shutter blade; and

using a shutter speed of the image acquisition, a shutter blade travels time for the camera, and a time from the occurrence of the predictor signal and/or event to the start of movement of the second shutter blade to determine the time from the predictor signal and/or event to the stopping of movement of the first shutter blade; and

a connection to the photographic lighting device in communication with the processing element for communicating the lighting emission initiation signal to the photographic lighting device.