Ingo Quendler
30.01.2004, 23:42
Hier der Rest des Dokuments (word) in englisch:
<a href='http://canonusapressroom.com/images/1DMarkIIWhitePaper.doc' target='_blank'>http://canonusapressroom.com/images/1DMarkIIWhitePaper.doc</a>
2. NOISE
High pixel counts come with the problem of inherent digital noise because smaller pixels require more amplification. Because the Mark II uses a large sensor with a lens magnification factor of only 1.3x, its pixels are a generous 8.2 microns square with excellent light-response characteristics and dynamic range. The Mark II has the widest ISO speed range of all EOS digital cameras.
Canon has developed an intensely clever new on-chip microlens array that gathers light for the photodiodes. By enlarging the diameter of each microlens and reducing the gaps between them, the sensors receive more light and less is lost. This, too, means more image signal and less noise.
Canon’s in-house development of its CMOS sensors has reduced both fixed-pattern and random noise. Of the two, the first is, of course, easier to deal with because you know where it is and can subtract it from each file. The Mark II has a second generation, on-chip noise elimination circuit that effectively reduces both kinds of noise. For longer exposures, the camera cuts off driving and output current and, starting at 1 second, Dark Frame Subtraction is automatically applied, removing any non-image signal remaining.
Because the CMOS sensor consumes less power, its signal-to-noise ratio is less affected when the sensor’s temperature rises, as in longer exposures. The irregular colors occurring along image edges and corners during long exposures with other sensors have been mostly eliminated. Even when photographing stars at night, the EOS-1D Mark II has extremely low noise.
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Moderator: Ingo Quendler
Dieser Beitrag wurde am 30.01.2004 um 23:53:35 editiert.
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<a href='http://canonusapressroom.com/images/1DMarkIIWhitePaper.doc' target='_blank'>http://canonusapressroom.com/images/1DMarkIIWhitePaper.doc</a>
2. NOISE
High pixel counts come with the problem of inherent digital noise because smaller pixels require more amplification. Because the Mark II uses a large sensor with a lens magnification factor of only 1.3x, its pixels are a generous 8.2 microns square with excellent light-response characteristics and dynamic range. The Mark II has the widest ISO speed range of all EOS digital cameras.
Canon has developed an intensely clever new on-chip microlens array that gathers light for the photodiodes. By enlarging the diameter of each microlens and reducing the gaps between them, the sensors receive more light and less is lost. This, too, means more image signal and less noise.
Canon’s in-house development of its CMOS sensors has reduced both fixed-pattern and random noise. Of the two, the first is, of course, easier to deal with because you know where it is and can subtract it from each file. The Mark II has a second generation, on-chip noise elimination circuit that effectively reduces both kinds of noise. For longer exposures, the camera cuts off driving and output current and, starting at 1 second, Dark Frame Subtraction is automatically applied, removing any non-image signal remaining.
Because the CMOS sensor consumes less power, its signal-to-noise ratio is less affected when the sensor’s temperature rises, as in longer exposures. The irregular colors occurring along image edges and corners during long exposures with other sensors have been mostly eliminated. Even when photographing stars at night, the EOS-1D Mark II has extremely low noise.
================================================== ========
Moderator: Ingo Quendler
Dieser Beitrag wurde am 30.01.2004 um 23:53:35 editiert.
================================================== ========