LCoS Shoot-Out Hardware and Software
Dr. Raymond M. Soneira
President, DisplayMate
Technologies Corp.
Copyright © 1990-2006 by DisplayMate
Technologies Corporation. All Rights Reserved.
This article, or any
part thereof, may not be copied, reproduced, mirrored, distributed or
incorporated
into any other work without the prior written permission of DisplayMate
Technologies Corporation
Article Links: Overview Part A Part B Part C Part D
LCoS HDTV
Manufacturers Sidebar
Shoot-Out
Hardware and Software Sidebar
Printing: If your browser is
improperly printing some pages with text cutoff
on the right edge then either print
in Landscape mode or reduce the font
size (View Menu - Text Size) and
margins (File Menu - Page Setup).
Digital Signal
Distribution:
For the Shoot-Out we had 5
digital signal sources and 6 HDTV displays that needed to be connected
together, which is a reasonably complicated configuration. The entire signal
distribution system was provided by Gefen Inc, a well established and
highly regarded company that has a broad product line of DVI and HDMI interface
products for both video and computer applications. All of their video products
are HDCP compliant and support signals up through 1080p. Some combinations of
DVI and HDMI products don’t always work well together because of subtle compatibility
and timing issues. With 5 signal sources and 6 HDTVs there were 30 combinations
that had to work together (not counting the Gefen hardware itself). HDCP
compliance adds another level of complexity because each connection requires
its own unique encryption channel that has to be negotiated separately. I was
worried that some of the combinations might not work so I had a complete backup
analog distribution system ready just in case. Fortunately, I didn’t need to
use it because all of the combinations connected through the Gefen based
digital signal distribution system worked flawlessly through the multiple
layers of switchers and distribution amplifiers, and in many cases through 5
meter DVI/HDMI cables running 1080p signals. It was an impressive and flawless
performance. The heart of the system was Gefen’s 6×2 HDMI Switcher. It
has 6 inputs, two outputs and a really handy infrared remote control (that can
be programmed into to your Home Theater’s master remote in order to provide
automated switching). We also had three Gefen DVI Distribution Amplifiers: a
2×8 for the main system distribution and two 1×4 units for the 720p and 1080p
signal feeds. The 2×8 unit could switch between two inputs using a remote
control. Our ATSC HD broadcast tuner and D-VHS player were very far away from
the Shoot-Out setup so we used Gefen’s HDTV CAT-5 Extender to deliver the 1080i
signals over twin 75 foot long CAT-5 cables. Gefen also provided the long DVI
and HDMI cables needed to connect the HDTVs to the Distribution Amplifiers – up
to 5 meters in length. They all worked flawlessly up through 1080p. All of this equipment is equally suitable for both
consumer and professional installations. See www.gefen.com.
Spectroradiometers:
Obtaining very accurate
photometry and colorimetry for all of the HDTVs was an absolute requirement for
a comparative study like the Shoot-Out. A Spectroradiometer was necessary
because the light spectra for the HDTVs are sufficiently different that the
more common and inexpensive colorimeters would have delivered inaccurate
results (see Part I
for an explanation). We verified this firsthand when one of the manufacturers
brought their own high-end colorimeter to the Shoot-Out. Colorimeters need to
be recalibrated for each distinct light source by using a Spectroradiometer.
The Konica Minolta Instrument Systems Division loaned us two of their
high-end Spectroradiometers, the CS-1000, the same instrument we used in Parts
I-IV, and the newly introduced CS-200. The CS-1000 is their flagship 512
channel Spectroradiometer, the new CS-200 is a 40 channel unit that uses a
spectral fitting method to match the CIE functions. It's much faster and much
less expensive than the CS-1000. In fact, it's a factor of 10 faster so there
was a very big time savings with the 5 LCoS HDTVs and CRT monitor. Before using
the CS-200 I wanted to compare it directly with the CS-1000, so Konica Minolta
generously loaned me both. When I compared readings from the two instruments,
the maximum luminance difference was 0.6 percent and the average absolute
chromaticity differences were 0.0005 for u' and 0.0002 for v'. The agreement
was very impressive and significantly better than the published specifications.
This assured me that I could use readings from both of the instruments
interchangeably. The user interface on the CS-200 was also really nice and a
big time saver as well. Both instruments are highly recommended. See www.konicaminolta-usa.com.
Video
Processors:
When I began planning the
Shoot-Out I didn’t realize how many video processors were going to be involved.
All told there were 8: 5 from Silicon Optix and 3 from DVDO. Two units arrived
with prototype Silicon Optix processors for their front-end signal processing
(eLCOS and JVC Professional), the Denon DVD-5910 had one Silicon Optix
processor for deinterlacing and one DVDO processor for scaling, and then we had
two processors from Silicon Optix and two from DVDO to help with the general
signal distribution system. In addition to high quality deinterlacing and
scaling these processors provide excellent front-end signal processing with
lots of special functions and advanced controls for adjusting and tweaking
picture quality.
We had 2 DVDO iScan HD+ processors from Anchor
Bay Technologies. I selected them based on the great review they received
from Widescreen Review Magazine Video Technical Editor Greg Rogers in the
February 2005 issue, and they performed really well as expected. One very nice
feature of these processors is the regular software upgrades provided by DVDO
that enhance the functionality of existing units. One unit was used as a
front-end processor and transcoder for the reference CRT studio monitor to
convert the distribution DVI signal into analog YPbPr and scale it to 1080i for
the monitor. The other was used for a number of functions such as adjusting DVI
signal timing and providing control adjustments that were not available on some
units. They were very important components in the Shoot-Out. DVDO also supplied
some excellent video cables to help connect many of the signal distribution
components. See www.dvdo.com.
We started out with 2 Silicon Optix video
processors. They were both Niobe Reference Design prototypes and provided 1080i
motion adaptive deinterlacing and rescaling. They use a Realta programmable
video digital signal processing chip that can be updated or enhanced with
downloadable software. Most HDTVs and video processors currently only offer
480i motion adaptive deinterlacing and then provide some form of line
interpolation at 1080i. When I saw the major picture quality improvements from
the Niobe 1080i deinterlacing I asked for two additional processors to act as
the main 720p and 1080p signal feeds for the HDTVs because I didn’t want
differences in signal processing to confuse the LCoS picture quality issues
that we were evaluating. These prototypes were already very impressive and will
find their way into many branded products. Look for the Realta, HQV, Hollywood
Quality Video, and powered by Teranex identifiers. See www.siliconoptix.com and www.hqv.com.
Microsoft
Digital Media:
About half of the High
Definition program source material shown to the panelists was provided by the
video codec group of the Microsoft Windows Digital Media Division. They
provided a PC with dual 3.4 GHz Xenon processors running Windows XP Media
Center Edition 2005 and loaded with a large selection of movie clips and
trailers encoded with Windows Media 9 Series at 720p and 1080p. We also used
two Windows Media Video HD segments from Joe Kane’s Digital Video Essentials:
Professional Edition (ABC TV’s New York City segment and Restaurant Ambiance).
The material was all of very high quality and free of the annoying Mosquito
Noise that generally accompanies MPEG. It was the hit of the Shoot-Out and many
people commented that the Windows Media HD movie clips looked better on the
HDTVs than they did in the movie theaters. See www.wmvhd.com.
D6500 Bias
Backlighting:
Carefully controlling the
ambient room lighting is very important in order to obtain the darkest possible
black-levels and minimize eye fatigue. For front projection it’s best to watch
in near total darkness, but for any self-contained display (direct view or rear
projection) it’s actually much better to have some special lighting that gently
illuminates the wall area behind the screen. That way the light doesn’t hit the
screen and spoil the display’s precious black-level. As a bonus, this method
also reduces the visibility of the black-level background glow because it activates
the eye’s light adaptation mechanism, which reduces the eye’s light
sensitivity, so the black-level will appear darker. The constant (bias) glow
also reduces eye fatigue by stabilizing the eye’s adaptation response and
reducing the degree of iris activity. For the viewing tests portion of the
Shoot-Out we used 4 Ideal-Lume D6500 backlights. These are fabulous high
quality units specially designed for home theater and studio use. They have
special broadband fluorescent bulbs that produce an accurate D6500 light (which
I confirmed with the Spectroradiometers). They are manufactured and sold by CinemaQuest
Inc. Their website includes lots of great information and other related
products. The fixtures start-up instantly, are very quiet, and are painted black.
A filter kit allows the light output to be controlled. They are very well made
and come with excellent documentation. Every direct view or rear-projection
home theater should have one. Highly recommended. See www.cinemaquestinc.com.
DVD Player:
When I asked Widescreen Review
Magazine Contributing Editor Stacey Spears for a recommendation on a high-end
DVD player for the Shoot-Out I had already read his review of the Denon
DVD-5900 in the July 2004 issue, so I wasn’t surprised when he came back with
the newly updated Denon DVD-5910. Interestingly, the 5910 has two
built-in video processors – a Silicon Optix processor for deinterlacing and a
DVDO processor for HD scaling. These are the same processors we used in the
signal distribution system and they perform beautifully. The 5910 is Denon’s
flagship DVD player and is as close to a perfect player as I have seen,
with an incredibly long list of advanced functional capabilities. Although DVDs
are only Standard Definition this Denon player made them look their best on the
HDTVs. See www.denon.com.
Test Patterns:
In order to do a thorough analysis of the performance and
artifacts of the HDTVs I used our own DisplayMate for Windows Multimedia
Edition running at 1920×1080 and 1280×720 resolutions on two Windows XP PCs that were
connected to the Gefen switcher. One had an ATI Radeon 9800 Pro graphics board
and the second an NVIDIA GeForce 6600 GT. Both have DVI and Component Video
outputs in addition to RGB, S-Video and Composite Video. I also used DisplayMate
for Windows Multimedia with Motion Edition running under Windows’98 with a
Matrox Millennium G550 graphics board. These DisplayMate products have over 500
proprietary High Definition test patterns, which are all generated real-time
from scale free mathematical equations so they run at any resolution and aspect
ratio. The incredible variety of artifacts is the reason why so many test
patterns are needed, plus there are test patterns for
setting up and adjusting all of the user and service controls, and test
patterns designed for use with instrumentation, such as the Spectroradiometer
measurements that we’ve used throughout this article series. All of our
DisplayMate tests were done at the native 1920×1080 and 1280×720 resolutions of
each unit. Note that test patterns based on DVDs will miss most of the High
Definition display and processing artifacts. See www.displaymate.com.
Article Links
Series
Overview
Part A: Introduction
to LCoS Technology
Part B: LCoS Color
and Gray-Scale Accuracy
Part C: Test Pattern
and Jury Panel Evaluations
Part D: Comparison
with CRT, LCD, Plasma and DLP
Sidebar: LCoS
HDTV Manufacturers
Sidebar:
Shoot-Out Hardware and Software
Copyright © 1990-2006 by DisplayMate
Technologies Corporation. All Rights Reserved.
This article,
or any part thereof, may not be copied, reproduced, mirrored, distributed or
incorporated
into any other work without the prior written permission of DisplayMate
Technologies Corporation
