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Objectives Values \u200b\u200bObjectives stabilized

stabilizing system allows a goal off the slight blur that occurs when you take a picture by hand, without support and, when the shutter release, we made a small movement objective. Is often referred to shake or vibration.
This happens usually at shutter speeds below 1/LongitudFocal, for size of full-format sensor. If your size is APS-C sensor, the threshold corresponds to somewhat higher velocities.
To understand the stabilization mechanism, the first thing we do is explain what the target's movement that attempts to compensate. This movement can be decomposed into two components, as shown in the figure.
A vertical component consisting of a complete rotation of the camera and with it the objective "about the axis X. From a practical standpoint, the goal pointing a little towards the sky or a little to the ground.
A horizontal component consisting of a complete rotation of the camera and with it the objective "about the axis Y. From a practical standpoint, the goal pointing slightly to the right or slightly to the left.
Clearly, any rotation around the Z axis, the optical axis, will not have any influence on the image due to the circular symmetry of the targets. From the practical point of view equivalent to slightly raise the right or left of the camera.
Sensors are informed of these movements and sends the data to a microprocessor that after calculating compensation, active engines that move slightly inside the objective lens. This has placed among the rest that make up the group and its sole mission is to reduce vibration. The attached figure is represented this lens, but not the rest of the group.
The stabilization system activation caused by pressing the shutter button halfway, in the same action in which activated autofocus. Naming
blur the issue makes sense, because the situation is somewhat similar to what occurs for points closer or more distant to the focal plane that contained within the limits of the depth of field. That different rays from a single point in the scene converge in a wider area than the circle of confusion and therefore it is blurred in the image.
Here, the process is somewhat different.
Consider, for simplicity that the jitter is only a vertical movement. And let's realize that the goal a little more pointed skyward.
In this case, the rays from any point in the scene belonging to the focal plane impact on the target in different areas and different angles. So some intersect the image plane in an area outside the circle of confusion centered on the image point. In this way we obtain a blurred image of a point, because they belong to the focal plane, should generate the image plane in a circle (formed by all the rays that reach it by following different paths) below the circle of confusion. Obviously, this same reasoning applies to all items included within the limits of the initial depth of field.
The work of the stabilization system, in this case, slightly move the lens correction through the use of vertical motor so that the entire target system do impact the beam at the image in its original position within the circle of confusion.
Through this mechanism can coseguir reduce the shutter speed 3 to 4 steps, without showing the blur caused by vibration. Of course, not all the time.