Shutter; New Viewfinder And Interchangeable Focusing Screens - Canon EOS 40D White Paper

Shutter

New Viewfinder and
Interchangeable Focusing
Screens
With DIGIC III Image Processor, DDR SDRAM and a circuit design to take advantage of
their maximum performance, the maximum burst at approximately 6.5 fps is approxi-
mately 75 shots in JPEG Large/Fine and approximately 17 shots in RAW. By comparison,
the maximum bursts for the EOS 30D were 30 Large/Fine JPEGs and 11 RAW. (These figures
are based on Canon's testing standards with a 1GB CF card. The maximum burst during
continuous shooting varies depending on such factors as subject, CF card brand, ISO
speed, and Picture Style.)
In Low-speed continuous drive mode, the EOS 40D fires at approximately 3 fps. The
drive mode selection loop now includes a 2-sec. self-timer.
While it is based on the EOS 30D's mechanical shutter unit, the shutter of the EOS 40D
is now more reliable with a contactless switch instead of a contact switch for running
the 1st and 2nd curtains. Shutter durability is approximately 100,000 cycles, the same
as the EOS 30D's shutter. The shutter release lag time with SW-1 ON is approximately
0.059 sec. between SW-2 ON and start of exposure. The time lag between simultaneous
SW-1/SW-2 ON and the start of exposure is approximately 0.126 sec. Time lag is calculated
with the aperture stopped down 3.5 stops or less and excludes AF operation time.
Viewfinder blackout time is about 0.1 sec.
The self-timer now offers a choice of
2 sec. or 10 sec. delay. The shorter
time is useful for eliminating blur
caused by the camera shake associated
with release technique in situations
such as landscape or close-up photography. With a fully-charged Battery Pack BP-511A,
a bulb exposure can be as long as about 2.5 hours.
In addition to the mechanical shutter, the EOS 40D has a 1st curtain electronic shutter
that is a key component in the Live View Function.
The EOS 40D has a new, enlarged and optimized
pentaprism and a larger diameter eyepiece lens.
The viewfinder looks bigger with less vignetting
(edge cut-off). To make the viewfinder clearer and
easier to see, the magnification is 0.95x, the angle
of view is 26.4°, and the eyepoint is 22mm. By
comparison, the EOS 30D's viewfinder gave 0.9x
magnification, a 25.1° angle of view, and a 20mm
eyepoint. On both cameras, the coverage is 95%
and the dioptric adjustment is -3 to +1.
III. PERFORMANCE
Shutter-Release Stroke and Pressure
State
Stroke
Shutter button protrusion 1.3mm
Standby position to SW-1 ON 0.55mm
SW-1 ON to SW-2 ON 0.3mm
Viewfinder Coverage Comparison
Fig. 46 Viewfinder coverage comparison
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: EOS 30D viewfinder coverage
Pressure
–
140g
330g
13