Why use anti-shake
Just started to use digital camera friends often encounter problems: your own shooting out of the picture is not clear enough, always occur ghosting or fuzzy.
This is why? in addition to the occasional loss of focus (that is, the camera fails to correctly focus), largely because of the shutter speed is too low. In General, in the handheld, shooting to clear photos of shutter speed should reach the focal distance countdown or even higher.In actual shooting, the photographer's hand in film or CCD/CMOS photographic process of jitter is objective and existent, prevention is prevention, can only rely on the machine's special "anti-shake" function to decrease as the photographer's hand jitter caused by image blur.
Anti-shake technology analysis
Currently, anti-shake three types: optical anti-shake, sensor (CCD) anti-shake, natural anti-shake (ISO anti-shake).
Optical anti-shake is dependent on the lens of the gyroscope detects tiny mobile and will signal transmission to the microprocessor immediately evaluated need compensation of displacement, and then through the lens group, under the direction of the camera jitter and displacement quantity to be compensated, thereby effectively circumvent the camera vibration generated image blur.
Photoreceptor anti-shake CCD principle is — the anti-shake is housed in a CCD can move around on the bracket of the first detect whether dithering, and sensors detect dithered direction, speed, move the volume ...
Detection of signal processing to calculate can offset jitter of CCD amount to achieve the anti-shake is moved.The above principle of two anti-shake is similar, namely through the camera's internal staff of mechanical movement to compensate jitter to achieve the anti-shake effect.
At the same time, the anti-shake technology will result in lower Imaging sharpness. After all, the speck much floating lenses, which require high photographic enthusiasts, it is not good; so this is why the anti-shake system will have a switch, users can select Cancel or turn the anti-shake; plus the anti-shake system is very low, so you generally do not open the anti-shake switch, but only when you want to use to open, if instant capture moving objects that may be because many of these steps and missed opportunity.Natural anti-shake is ISO anti-shake.
His research interests at the time of the adoption of genuine e-mail. That is, increase the ISO, shutter speed reached anti-shake.Because the camera has a security shutter (that is, ensure that the image is not blurry shutter speed), the general sense of security shutter speed to 1/60 second, lower than the shutter speed is likely to be photographed image blur.
Suppose that in the same scene under the same display, the exposure is the same (same screen environment definitely identical exposure no doubt), if the aperture unchanged, if ISO improves, inevitably lead to shutter speed so that the original did not reach the security shutter shutter speed, ISO increase of cases it is possible to reach even more than security shutter, natural anti-shake is achieved through such a tad better. The anti-shake effect compared to the other two anti-shake effect even have gone.Anti-shake optical anti-shake VS nature
Test conditions
Let's choose a price equivalent, with optical anti-shake function of other brand camera (A) and a digital camera with natural anti-shake (hereinafter B) do the comparison, in the same fluorescent circumstances, adopt the following props, can swing to the left is the "head" on the right you can move the "platform", in the same frequency shaking, I made the following three conditions test: the camera moved
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