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To match Ikegami's new HL-DV7W 16:9 DVCAM camera, I was lucky anough to used one of Canon's new J11ax 4.5B IFXS Broadcast Television Lense... (my write up continues below)

J11ax 4.5B IFXS Broadcast Television Lenses being used on White light

Similar to the PAG System, the J11ax 4.5B IFXS was a perfect match. To be honest I wondered about the price difference between the EFG and the Broadcast Television Lenses, I can tell you having digitized the first half of the feature film, the difference is amazingly self evident... The sharpness is incredible, especially for a wide angle lense... Also the contrast and resolution is truly remarkable. I love Wide Angle shots, where the scene play out inside the frame... I tested both Angenieux and Fujinon lenses before using the Canon J11ax 4.5B IFXS , when I buy a lense, this will be it... (When I do a test 35 mm transfer, I'll invite everyone who wants to come and you'll see what it can do...) Like the rest of the kit, we have thrown a lot at the lense and its never failed. Two features once I started to use I couldn't do without, 'Shuttle Shot' and 'Framing Preset', the first for focus, being able to hit a button which will crash zoom the lense into check focus and then back and the second, 'Framing Preset' which means I can play around with different focal lengths and then be able to get back to my original frame, both really handy when you are making independent films.


A SUPER WIDE LENS ACHIEVING 4.5mm, SURPASSING 100° IN DIAGONAL

J11ax 4.5B IFXS Broadcast Television Lense

INTRODUCTION:

Canon have now releases the third generation of IFxs series, the J11ax4.5B. This ultra wide lens follows the design concept known as IF-XS which incorporates Canon's power optical system and features the X-element. IF-XS allows for a smaller more compact size with increased specifications making the J11aX4.5B the widest lens in the world.

The new J11aX4.5B provides wide images never previously possible with an 88.7° angle of view at the wide end in standard 4:3 mode, 93.7° in 16:9 mode and 101° diagonal in the 4:3 mode. The focal length at the wide end is 4.5mm- 16% wider than the current J9aX5.2B.

This Digital drive lense features shuttle shot, speed preset, framing preset as well as other useful features.


FEATURES:

Surpassing 100° in diagonal

Ultra widest angle of 88.7° (4:3 Format)/93.7° (16:9 Format) at 4.5mm is achieved with reduced distortion.

High zoom ratio 11X

Crossover Mode

For 16:9/4:3 switchable cameras, Option.

Built-in 2X Extender

Vari-Polar Hood

Supports high grade filter work 120 degree rotation for Polarized Light Filters, Cross Filters etc.

Quiet Servo Operation

Mass (1.78kg)

Lightest mass in it's class.

Shuttle Shot

By Memorizing any two focal lengths, the Digital Drive can automatically "shuttle" between the two points at its highest speed, moving in either direction.

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. This is useful when a production requires the same zoom speed repeatedly, such as an interview program.

Framing Preset

An Angle of view can be preset in memory and the lens will zoom to that position by pushing a simple button. During a performance, framing preset will reproduce the zoom as often as you like at the highest speed or in a preset zoom speed.

Ergonomic Design and Ease of Use

It may seem that all of the added functions made available by Digital Drive will cause confusion to the cameraperson. On the contrary, the digital functions have become "Useful" by having only one memory button on the drive unit. If you have a production requirement where you will be shooting several different Sciences, each function can easily be set up by the use of on/off dipswitches.


QUESTIONS:

What is IF(Internal Focus)?

Internal focusing for a TV zoom lens can simply be explained as the application of floating to the front group of a zoom lens.

If the front group is split into two or three subgroups and the inner subgroup is moved for focusing, the front and rear spaces of the focusing group are changed. The difference of the influences of the two spaces on the aberration is used to compensate the change in aberration during focusing. Internal focusing works only when the distribution of aberration between the fixed group and the focusing group is appropriately designed.

Characteristics of the internal focusing system

l. Improvement in optical performance:

It is possible to improve the optical performance by making use of the larger degree of freedom of aberrations correction. The performance has been improved to increase the angle of view, reduce the change in chromatic aberration during focusing, reduce distortion, etc.

2. Square hood.

A square hood can be used because the barrel of the front group is stationary. In conventional lenses the hood had to be circular because the front group was designed to rotate. The internal focusing lens can eliminate ghosting and flaring more effectively than the conventional lens by cutting unnecessary light fluxes at the square hood, and is thus well suited for CCD cameras.

3. Reduction of the weight of the focusing lenses group.

This is an important factor in terms of operation. The focusing lens group, which is lighter than those in a conventional lens, can be moved quickly using little electric power, enabling smooth movement even during manual operation.

4. The use of filters.

The hand held lens is used with various filters attached to front barrel. However, the filters whose properties change with rotation, such as polarising filters, cross filters, and half ND filters, were difficult to use with a conventional lens whose front portion rotates. These filters can be used with the internal focusing lens without any problem because the front group does not rotate, thereby enabling the filters to be used to their full effect.

5. Optical accessories.

Optical accessories, such as a wide converter or tele-side converter attached to the barrel of the focusing operation. A handy mattebox can be attached directly to the barrel of the front group.


What is Crossover?

The next generation of television broadcast format is moving in the direction of the 16:9 aspect ratio. However, broadcasters still must accommodate viewers who have TVs that work in the 4:3 aspect ratio. This requires broadcasters to maintain the existing format of the 4:3 aspect ratio. While adding equipment capable of the 16:9 aspect ratio. To serve in this mixed format environment, Canon has developed a crossover system for switchable CCD cameras that can switch between these two aspect ratios.

Aspects of the Canon crossover-system.

1. One of the common methods of 4:3 / 16:9 image switching by CCD is to cut off the image at both ends, leaving the centre portion as the effective image area. This results in a smaller image area for the switched 4:3 format (dia. 9mm) when compared to the 16:9 and conventiona1 4:3 formats (dia.11mm).

2. As the diameter of the image shortens under the condition of the switched 4:3 format (dia. 9mm), the ang1e of the lens becomes more telephoto. Consequently we lose about 20% of the angle at the widest focal length in comparison with the 16:9 format (dia.11mm).

3. To enable operations with the same picture angles in the two different format sizes, a 0.8x crossover unit is employed. This shortens the focal length of the lens to achieve the same angle as the conventional 4:3 format (dia. 11mm), under the switched 4:3 format (dia.9mm) condition. Accordingly a conventional 2.0x extender in the 16:9 format (dia.11mm) turns out to be a 2.4x extender under the switched 4:3 format (dia.9mm).

4. The extender unit of the crossover system includes a crossover lens in addition to conventional extenders.

Crossover-system for Portable lens.

There are 2 different types of Crossover ENG/EFP lenses available. One is the WRSD/WASD version which incorporates a 0.8x Crossover unit in addition to the 2x extender. The other is the VRSD/VASD version which has a 0.8x Crossover instead of a 2x extender.


SPECIFICATIONS:

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