Hi-UD Glass
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NTSC 400TVL(30lp/mm)
F1.6
HDTV 600TVL(55lp/mm)
Defocus(mm)
MTF(%)
Canon’s New HDgc Series
KH16ex5.7 IRSE
Canon’s Philosophy:
Canon has always developed new technology with four basic philosophies, "High Quality of Picture", "Ease of Operation",
"High Specification" and "Minimize Environmental Impact". Canon's HDTV lenses are, so to speak, a compilation of our
basic philosophies. Now, Canon adds a new concept to the HDTV lenses by launching the new HDgc Series.
Concept of HDgc Series
Corresponding to the popularity of digital High Definition broadcasting and diversity of HDTV
equipment, Canon has added a new series to its HDTV lens line up, the HDgc series. The new HDgc
series supports the emergence of an important new generation of cost-effective HD acquisition systems.
Adopting the advantages created by Canon’s unique technology, the new HDgc lenses exhibit high
MTF, high resolution and high contrast from the center of the image to its extreme edges, meanwhile
maintaining its compact size and weight.
Another important policy of Canon’s is not to pollute the earth and the HDgc series succeeded in
excluding harmful substances such as cadmium, PBBS, PBDPE or mercury from the mechanical parts,
and at the same time incorporating lead free glass and reducing the amount of hazardous substances
used in electrical parts.
Meet Canon’s new HDgc series lenses, a compilation of Canon’s advanced technologies.
Optical Performance of HDgc Series
Aberration Correction for HDgc Lenses
In the HDTV system the pixel size is about half. Therefore, the spread of a point image caused by a
spherical aberration, coma etc. should be diminished to about half. The MTF varies as the focus
changes and even if the image is slightly out of focus, the MTF is greatly influenced as shown in
Graph 1. HDgc greatly contributes to correcting and minimizing these aberrations at the same time
maintaining high MTF throughout the edge of the picture.
Special Optical Elements
With the goal of minimizing chromatic aberration, the HDgc series lenses utilizes special elements
including an artificially re-crystalized element, “Fluorite”, with extraordinary dispersion characteristics
and the newly developed “Hi-UD” (high index ultra low dispersion) glass. Canon has succeeded in the
practical use of special elements along with advanced design techniques like “separate achromatism”.
The KH16ex5.7 carries Canon’s original Enhanced Digital Drive, a drive unit equipped with an information display and a digital function
selector so that the user can customize the enhanced digital functions much more easily and precisely. The new design enables the user to
fully bring out the digital functions.
Main Features
Shuttle Shot : By memorizing any two
focal lengths, the digital drive can
automatically "shuttle" between the two
points, moving in either direction.
Framing Preset : An angle of view
can be preset in either of two memories
and the lens will zoom to that position
by pushing a simple button. During a
performance, framing preset will reproduce the zoom
position decided upon at the rehearsal. It is easy to repeat
the same zoom as often as you like at the highest speed or
in a preset zoom speed.
Speed Preset : A specific zoom speed
can be preset in memory and it is
possible to repeat the zoom speed as
often as you like by pushing a simple button.
(Display Image)
Enhanced Digital Drive