![]() Identify the points on B and C that intersect with D.Ģ. This value represents the predetermined level of blurring that is just enough for the CIPA panellists to know that image stabilisation was performed.ġ. Determination level for image stabilisation performance (D): It is difficult to determine whether any image stabilisation took place if very little blurring occurred. This is derived from the results obtained with the vibratory apparatus. Measured motion blur amount (C): A value that represents the residual motion blur when IS is turned on. Reference motion blur amount (B): A value that represents the amount of blurring without IS. Source: Figure 4-5-3b Image Stabilisation Performance Calculation Method, from “Measurement and Description Method for Image Stabilisation Performance of Digital Cameras (Optical System)” published by CIPA. Method for calculating IS performance based on the CIPA standardĭ: Determination level for image stabilisation performance Canon has said that their DSLRs “are able to operate at low shutter speeds of up to 30 seconds”.ģ) The conditions created by the vibratory apparatus differ from actual camera shake, so the published number of IS stops might not completely match what a user experiences when using the camera. The slowest shutter speed where the IS system is effective is unknown and probably differs between cameras. The results of the shots are determined using a dedicated blur measurement software, and the effective number of stops indexed according to the calculation method described below.ġ) To prevent any fluctuations arising from differences in the technical skill of the photographer, IS performance is not measured using actual handheld shots.Ģ) In practice, camera shake is difficult to suppress when shooting with shutter speeds as slow as 30 seconds. Ii) The fastest shutter speed where the blurring is more than the predetermined benchmark.ħ. I) The slowest speed where the blurring does not exceed a predetermined benchmark (also known as the “determination level for image stabilisation performance”), and is repeated until two measurement results are obtained: The shutter speed is increased or reduced by at most one stop, and Steps 3 and 4 are repeated.Ħ. At least 200 shots of the motion blur measurement chart are taken under the same conditions (shutter speed, focal length, shooting distance etc).ĥ. Shooting is stopped after 30 seconds even if less than 10 shots are taken.Ĥ. Generally, a total of 10 shots are taken at shooting intervals of approximately 1 second. During vibration, the camera is used to shoot a motion blur measurement chart with the image stabilisation turned on. ![]() It is then subjected to either one or two types of mechanically-created vibration waveforms, depending on the total mass of the camera body, lens, memory media and battery.ģ. The equipment to be tested is set onto a vibratory apparatus.Ģ. This link has more information on the methods, but here’s a summary:ġ. The effective number of IS stops is measured and determined using methods established by the Camera & Imaging Products Association (CIPA). This suggests that the “IS On” example is just as sharp as if it were taken at around 1/100 to 1/125 second. In the above example, the RF24-105mm f/4L IS USM has an IS performance equivalent to approximately 5 shutter speed stops. It means that when you shoot with IS on, the camera shake correction effect looks like you were shooting at a shutter speed that is up to XX stops faster. What does “IS effect up to XX shutter speed stops equivalent” mean? This results in visible camera shake when IS is off. In this example, the focal length was 105mm but the shutter speed was 1/4 second, which is about 4 shutter speed stops slower than the 1/focal length rule. (Note: It cannot correct the blur caused when the subject moves!)ĮOS R/ RF24-105mm f/4L IS USM/ FL: 105mm / Manual (f/4, 1/4 sec) / ISO 800/ WB: Daylight Image stabilisation (IS) helps to correct the camera shake so that you can shoot at a slower shutter speed with little to no visible camera shake blurring. For example, in dark shooting conditions, you might need to use both your maximum aperture and a slower shutter speed to ensure that the shot is sufficiently exposed without too much image noise. However, it is not always viable to shoot at 1/focal length. “Camera shake” refers to blurring in the image caused by the movement of the camera, including movement caused by unsteady hands.Īs a rule of thumb, if you want to shoot handheld, your shutter speed has to be a at least 1/focal length seconds to prevent camera shake. How are these numbers measured? Read on to find out more. Image stabilisation performance is usually described in terms of shutter speed stops, such as ”equivalent to 5 shutter speed stops” or ”4 stop equivalent”.
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