Superapochromat
using the SD glass
Expensive super low dispersion glass
which has been used for TV Broadcast
lenses is used in the frontal part of the
lens to eliminate in an ideal manner the
secondary aberration occurring at the
telephoto side.
Remote extender
Tokina employed the extender system
which has been used for TV broadcast
zoom lenses in contrast to conventional
extenders attached to the rear end of a
lens, this extender has been incorpora
ted into its optical system itself from the
designing stage to ensure that an opti
mal extender most appropriate for the
lens should be developed. Moreover,
use of a motorized system for moving of
the extender has allowed it to be remote
ly controlled.
Triplet compensator
Tokina has solved the problem of a
deterioration of the center performance
at around halfway of the zooming range
with this compensator. The deterioration
is a characteristic commonly observed in
telescopic lenses with a high magnifying
power. A result of the Tokina's advanced
optical technologies, the compensator
prevents the deterioration from occurring
and achieves a high resolution over the
entire zooming range.
High resolution suitable for
3CCD cameras
The progress in the use of 3CCD cam
eras is remarkable in recent years. Pro
vided with a high resolving power, the
lens will allow you to fully utilize the cam
era's performance to obtain images in
bright colors with high resolution.
Employment of the internal
cam system
The system allows the cam grooves to
be cut by an easier gradient. This will
permit at the same time the strength of
the cam barrel to be increased relative to
that of the conventional system. An
increase of precision in the direction of
the optical axis has made it possible
for an ideal optical performance to be
achieved at a value almost identical with
thatofthedesign.Withadecreaseof
the load to the zooming and focusing
motors, the overall durability has signifi
cantly enhanced.
NORMAL GLASS
SD GLASS
SD(Super Low Dispersion)GLASS
Sofisticated Tokina's designing and manufacturing technologies are
incorporated with compact and light weight body.
secondary spectrum
secondary spectrum
Internal cam Normal cam
MTF (Modulation Transfer Function)
100
50
0
0 2 4.2
Image Height(mm)
Response(%)
Saggital(f=10mm)
Meridional(f=10mm)
Saggital(f=250mm)
Meridional(f=250mm)
Saggital(f=500mm)
Meridional(f=500mm)
TM50Z1040
(10-500mm 1:4.0)