ISO speed

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ISO speed

The international standard measurement of a camera's sensitivity to light, often simply called the "eye-so." For analog film cameras, the ISO is the "film speed," which is based on the chemical composition of the film. Changing ISO means loading a film with a different speed. With digital cameras, it can be changed by selecting a speed from the ISO menu, reconfiguring an electronic circuit that emulates film speed.

If the camera's shutter speed and aperture cannot be altered for certain scenes, changing the ISO is a third variable that can accomplish the desired exposure. In a digital camera, ISO can be set manually or automatically.

High ISO Noise
In a digital camera, higher ISO speeds are accomplished by amplifying the electronic output of the sensor, and some cameras have speeds up to ISO 10,000. However, the more signals are boosted, the more noise is generated, which is equivalent to the grainier image that appears in analog film at ISO 1600 and higher.

Unless a grainy effect is desired, shooting at ISO 64 and ISO 100 has always been the recommended norm. However, each generation of digital cameras is able to use a higher ISO with less noise, and higher and higher speeds are routinely used. Some digitals have ISO speeds up to 6400 and more, and most cameras also have high ISO noise reduction (NR) circuits that can be selected to help smooth the resulting images.

ISO, ASA and DIN
ISO ratings are equivalent to the original American Standards Association (ASA) film ratings; for example, ASA 100 is ISO 100. The ISO speed may also be designated with its DIN equivalent, which is popular in Europe. For example, ISO 100 can be stated as 100/21º and ISO 400 as 400/27º.
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Display Indicators: Self-timer Indicator, White Balance Mode, Shutter Speed, Shooting Mode, Iso Setting, Focus
98p (MP4, AAC) and enhancement of controllability over ISO setting or the amount of flash emission.
Longer exposures will be required once the Moon is completely covered in shadow and the camera's high ISO setting and remote shutter release that avoids vibration will be helpful.
1 aperture and a 1600 ISO setting for very low light.
With a tripod-mounted camera, lens (usually a wide-angle) at full aperture and a high ISO setting, the observer hopes that a bright meteor will flash through the field of view while the shutter is open.
While there's quite a bit of noise when shooting at the lowest ISO setting, the E-PL2's TruePic V imaging engine does an outstanding job at delivering richly detailed images with superb colour rendition.
Motion Detection automatically detects moving subjects and adjusts shutter speed and the ISO setting to compensate for camera shake and subject movement.
5fps, and a lower ISO setting of 100 (versus 200 on the D40).
The update, free to all EOS 7D owners, gives the camera more advanced shooting options, including an increase in the maximum number of burst images taken in the RAW file format (from 15i frames to 25ii frames) as well as the ability to process RAW image files directly in the camera and the option to set a maximum ISO setting in ISO Auto mode.
Indoor interiors can be enhanced by choice of a wide angle lens, tripod or simply uprating the ISO setting on your camera for that extra detail and better exposure.
Smart Sensitivity Control is very similar to adjusting the ISO setting in digital photography," said Leigh Rees, Agilent's XRD general manager.