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HIGH MTF PERFORMANCE
The next generation of 16:9 format has
become more widespread world-wide.
The height of the 16:9 format is 20%
shorter than that of the current 4:3
format, thus the scanning lines are 20%
greater(Fig.1). As a result, higher
resolution is required for the 16:9
format. In order to achieve this, the
SUPER55 provides the optimum
balance of aberrations by Hi-UD glasses
(High Index Ultra Low Dispersion
glass) and Canon's unique fluorite. The
SUPER55 succeeds in having the
higher MTF performance,
correspondent to 6MHz, necessary for
the 16:9 format.
CANON "CROSSOVER" SYSTEM
All the Super series of lenses, including
the new Super 55 are now optionally
available with "CROSSOVER"
compatibility. The 4 position extender
turret incorporates a 0.8x
"CROSSOVER" unit in addition to
the normal extenders i.e. 1.0x, 1.5x, or
2.0x (Fig.2). When the CCD switches
to the 4:3 mode, the extender turret
rotates to the 0.8x position. The 0.8x
"CROSSOVER" unit reduces the
diameter from 11mm to 9mm thus
shortening the focal length to produce
an identical picture angle. In essence,
the 0.8x "CROSSOVER" unit acts as a
1.0x extender for the switched 4:3
aspect ratio. Fig.3 shows the relation
between focal length and the
magnification of the extenders.
PJ55x9B IE 9-500mm 1:1.4
SUPER 55
535.9
384
F.B.=48 in air
122 122
125
135.5
150
DIMENSIONS
The extremely high performance levels of the "55xSuper" with its 9mm wide angle have been prefered over all other lenses in its class.
This lens will now be appreciated even more in the 16:9 format.
The new and improved "Super 55" can include Canon's optional "Crossover System" which accommodates for the loss of wide angle
in the 4:3 mode in some of the dual aspect ratio switchable camera systems. The redesigned circuitry of the "Super 55" realizes
improvements in RF noise protection and its improved mechanical design offers a modern look with easy accessibility for user
friendly maintenance. Of course , the "Super 55" includes the best features of the 55xSuper like the superb wide angle of 9mm , the
light weight of 18kg and the extremely sharp picture quality even at the telephoto side.
Fig.1
1X
2X
0.8X
1.5X
or Spare
(Option)
Crossover
(optional)
Fig.2
CROSSOVER SYSTEM
16:9 Scanning Lines
16:9 (dia 11mm) 4:3 (dia 9mm)
Extender Focal Length F stop Extender Focal Length F stop
0.8X 1.0X
7.4-407mm
1.4
1.0X
9-500mm
1.4 1.2X
9-500mm
1.4
2.0X
18-1000mm
2.8 2.4X
18-1000mm
2.8
Fig.3
WIDE ANGLE
FIELD ZOOM LENS
4:3
16:9
80%
100%