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Sony HD Telecine Review



I attended the demonstration at the ITS show of the new Sony HD telecine
prototype. For those of you that couldn't make this show, I thought I
would share my views of this demonstration.

First off, Sony's engineers should be commended on the brilliant
approach they came up with for correcting image steadiness. They use
several small capacitance sensors in the perforation area to measure the
vertical and horizontal position of the perforation. Since film base
acts like a dielectric, the capacitance value varies across the sensors
as the perforations go by the sensors. They use several small
capacitance sensors within the perforation area. By tracking the rise
and fall of capacitance across these multiple sensors, a horizontal- and
vertical-position correction signal can be produced. The X- and
Y-correction signals drive servos controlling two optical glass plates
which can shift the optical film image falling on the CCD area array
imaging block. To eliminate problems with dirt or damage in a particular
perforation, they measure 8 different perforations. I hope my
description was clear enough.

The telecine has eliminated the claw pull-down of the earlier Sony HD
telecines but still retains intermittant drive sprokets. The transport
was very noisy on the prototype as it transported IP for the demo. They
need to make it quieter as this would be very unnerving for clients
listening to their camera originals being transported. They are using
dual particle transfer rollers on the machine. The machine was operating
with a 1920 x 1035 active area array camera head imaging block from
their new HD camcorder. They said that they will replace it with a 1920
x 1080 array with the production unit. They showed image rotation by
rotating the imaging block. I was told they use a zoom lens to do
zooming. Not all the image positioning features were shown in the demo I
attended.

They are also using Kodak's approach of using a Xenon lamp with a light
integrating sphere for illumination. But they have taken a totally new
approach to telecine light control. They are using dichroic filters to
break up the light into red, green, and blue beams and then using
individual solid state light valves to control the color make-up and the
brief illumination (exposure) time of the film image onto the CCD area
arrays. The brief exposure time thus allows for the intermittant film
transport between illumination periods. The individual colors are
recombined back into white light for the illlumination of the film
image. They are using some additional diffusion material at the film
gate to eliminate scratches.

The finish of the prototype was quite nice. It looked like a product.
The prototype machine is smaller than I expected and looks like a
shrunken Cintel telecine. For the demo, Sony was using a DiVinci
controller but confirmed that a Pogle could also control it. The
telecine has multi-format rollers to allow both 35mm and 16mm film to be
transferred. For their demo, they transferred a 35mm IP trailer of the
"The Fifth Element."

Overall, the pictures looked pretty good. Sony's area array imaging head
is pretty quiet. S/N looked good although I discovered that they were
showing the demo with a Digital Vision HD DVNR. I asked them to run the
trailer again without it. Noise came up a little bit but dirt and
scratches became much more noticable. I do not think their approach to
diffuse illumination works as well as the Spirit DataCine since the
Spirit uses a light integrating cylinder with an illumination exit slit
much closer to the film plane. The sharpness of the Sony telecine looked
fine but I did detect some slight colorimetery problems which may be
solved with their refinement of their color masking coefficients. The
demos were in 1125I and they demonstrated downconversion to 525I. They
said it would be a multistandard machine capable of outputing both HDTV
and SDTV. However, Sony's area array approach does have some limitations
with regard to output of 2K x 2K data like the Spirit because of Sony's
fixed 16:9, 1920 x 1080 CCD area array.

The steadiness correction system worked very well. They shifted the
image scanning area to show the perforations. They turned the steadiness
corrector on and off. You could watch the perf edge locked steady and
then watch it float around. Very impressive. It will be interesting to
see how the correction system works with real world film with dirt in
the perforations and with perf damage. You should remember that
steadiness correction systems that use the perforation for reference are
great for camera films (assuming you use the correct perf for reference)
but do not fully correct the unsteadiness introduced in continuous
contact printing used in the production of most interpositives.

Sony said that the production system would be shown and sold at NAB
1998. They would not say what the price would be except that "the price
would be competitive with compabable telecines in the marketplace." Any
guesses as to who they are targeting????

I will finish by congratulating Sony on showing a very impressive
prototype, especially their unique approach to steadiness correction. It
is always great to see competition in the telecine marketplace which
provides incentives to manufacturers to produce better products at lower
prices. I would be interested in other people's opinion of this machine
who saw the demo. 

So what's it going to be for HD --- Sony's new machine, Philips' Spirit
DataCine, Cintel's C-Reality, and don't forget the good old Rank Cintel
Mark III being fully hot-rodded to HD by the likes of Dave Walker and/or
Dave Schnuelle. We live in interesting times....

-- 
*******************************
* Brad Hunt                   *
* Sr. VP, DVD & Imaging Tech. *
* All Post, Inc.              *
* 1133 N. Hollywood Way       *
* Burbank, California 91505   *
* Phone: +1-818-556-5756      *
* Fax: +1-818-556-5748        *
*******************************

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