Wednesday 5 April 2017

image stabilization - What is 5-axis optical stabilisation? How does it work?


Some cameras like the Olympus E-M1 have what's called 5-axis optical stabilisation, which produces reasonably sharp handheld photos even at 1.6 seconds:


enter image description here Source (search for "HANDHELD AT 1.6 SECONDS Shutter Speed")


How does this differ from the more common types of stabilisation in lens or bodies (such as sensor shift)? Are there any cons to 5-axis stabilisation? Why do we need 5 axes when three are enough to move in any dimension?



Answer



Olympus has a video explaining it. They show all axis with each one designed to compensate for a type of movement. It is an evolution of sensor-shift stabilization:




  • Originally, when Konica-Minolta invented Sensor-Shift stabilization, the sensor moved along two axis, vertical and horizontal. This compensates for the camera moving along a plane as long at it remains level and does not alter orientation.

  • Pentax then implemented their own Shake-Reduction system using sensor movement. They used the same basic design and introduced rotation which compensate for movement in the tilt-axis. This improves camera movement correction because when the shutter-release is pressed, the camera tends to tilt which is not compensated for with the original 2 axis.

  • Olympus then created the 5-axis stabilization system that lets the sensor rotate along 2 more axis, corresponding to camera pitch and yaw. This makes it possible to compensate for even more type of movements and allows to stabilize images while the photographer is moving.


These are 3 axis of rotation and 2 axis of translation. One could attempt to compensate for a third translation axis, I suppose, but the remaining one probably has less effect on image sharpness as focus is probably sufficiently sharp within a certain tolerance, while other type of movements do show as inconsistent sharpness.


No comments:

Post a Comment

Why is the front element of a telephoto lens larger than a wide angle lens?

A wide angle lens has a wide angle of view, therefore it would make sense that the front of the lens would also be wide. A telephoto lens ha...