Canon EOS 20D Service Manual page 15

General Information
(3) Shutter
The camera has a newly-developed, APS-C-dedicated,
compact, high-speed shutter. With shorter shutter blade
edges, the shutter curtain speed is faster. This enables a
top shutter speed of 1/8000 sec. and X-sync at 1/250
sec. The shutter durability also surpasses that of the
EOS 10D (about 20).
(4) Exposure control
The shooting modes, basic features, and metering
sensor are the same as the EOS 10D's. The default increment for the
exposure setting has been changed to 1/3 stop. (This can be changed to 1/2
stop with C.Fn-06-1.)
Fig. 011 Mode Dial
(5) Viewfinder
Improved eyepiece optics enable a viewfinder magnification of 0.9x. The
focusing screen is a Precision Matte screen developed to make manual
focusing easier. The differences between the Precision Matte screen, the New
Laser Matte screen found in the EOS 10D, and the Laser Matte screen found
in the EOS-1D are shown below.
[Focusing ease]: New Laser Matte < EOS 20D < Laser Matte
[Viewfinder brightness]: New Laser Matte > EOS 20D > Laser Matte
The white balance correction indicator has been added to the viewfinder
information display.
(6) Built-in flash
When the built-in flash or an EX-series
Speedlite is used, E-TTL II autoflash takes
effect for high-precision and stable flash
exposures.
Thanks to an improved fresnel lens, the
flash coverage matches the 17mm focal length
even when the Guide No. (GNo. 13, ISO
100 in meters) remains the same as before.
Also, the built-in flash now uses a pop-up arm. The distance between the
optical axis and the center of the built-in flash is 18.6 mm longer than with
the EOS 10D. This reduces the incidence of red eye and reduces the chances
of the lens obstructing the flash coverage.
Fig. 012 Metering sensor
10
Fig. 010 Shutter unit
Fig. 013 Metering zones
Fig. 014 Built-in flash