The EOS-1Ds Mark III is compatible with UDMA (Ultra Direct Memory Access), a new CF
card specification (CompactFlash Specifications Revision 4.0) enabling high-speed writ-
ing to the CF card. With a UDMA CF card, the high-speed data transfer is about twice as
fast as the EOS-1D Mark III (about 3 times as fast as the EOS-1Ds Mark II). Although the
EOS-1Ds Mark III has twice as many pixels as the EOS-1D Mark III, the writing speed per
file is about the same as the EOS-1D Mark III, which is quite amazing.
The camera is compatible with SD memory cards including SDHC (SD High-Capacity)
cards. The writing speed with SD cards is the same as that of the EOS-1D Mark III.
Viewfinder
Large, bright viewfinders are an inherent advantage of full-frame sensor DSLR cameras.
The viewfinder of the EOS-1Ds Mark III incorporates a totally redesigned pentaprism and
refined eyepiece optics to make the viewfinder performance of the EOS-1Ds Mark III the
best in its class. Remarkably, the viewfinder provides the highest magnification and widest
coverage in the history of EOS-1 series cameras, including film models, approximately
0.76x and 35°. This is a substantial improvement over the EOS-1Ds Mark II. The new
finder also corrects the distortion in EOS-1Ds series cam-
eras to make the large viewfinder look more natural. The
100% viewfinder coverage, approximately 20mm eye-
point, -3 to +1 dpt dioptric adjustment range, and eye-
piece shutter are the same as the EOS-1D Mark III's. It is
now an even greater pleasure to look through the finder
and the point of focus is much easier to find and follow.
Major Viewfinder Specifications
Coverage [Approx. %]
Magnification [Approx. X] (Viewing angle [°])
Eye point
Dioptric adjustment
As with the EOS-1Ds Mark II, glass with a high refrac-
tive index is used for high performance. To match the
higher viewfinder magnification (wider viewfinder cov-
erage), the pentaprism and SI prism have been made
larger, necessitating a change in the top
exterior cover of the camera's body.
The lens type and glass selection have
been changed to make the eyepiece
lens larger. By having 4-lens elements
in 4 groups for the eyepiece optics,
flare is suppressed.
IV. DISCUSSION OF NEW AND IMPROVED FEATURES
Item
1Ds Mark III
100
0.76 (35.0)
Viewfinder Coverage Comparison
EOS-1D Mark III coverage
EOS-1Ds Mark II coverage
EOS-1Ds Mark III coverage
1Ds Mark II
5D
100
96
0.70 (31.9)
0.71 (32)
Approx. 20 mm
-3 - +1 dpt
Viewfinder Optics 1
SI lens 1
SI mirror
SI lens 2
Metering
sensor
V-LCD
prism
V-LCD
Eyepiece lens
1D Mark III
100
0.76 (28.3)
SI-LCD
Pentaprism
Backlight lens
SI-LED
Metering lens
Condenser
lens
Focusing
screen
SI prism 1
SI prism 2
H-LED
H-LCD prism
14