Sony G90 manual Performance, Summary

Models: G90

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ter or a motion-adaptive 3-D comb filter when using the

composite input.

Performance

My overwhelming first impression of the Sony G90 was its

razor-sharp image clarity. The 9-inch CRT technology reveals

the resolution limits of projectors with smaller CRTs. I sup-

pose it was even more impressive that the first things I looked

at were HDTV pictures. But the differences in detail between

the Sony G90 and the excellent but smaller CRTs of the Runco

IDP-980 Ultra, were also noticeable on DVD. Edges were a tad

sharper and areas of fine structure appeared to have addi-

tional depth and contrast.

The G90 has an outstanding ability to differentiate subtle

levels of dark gray just above black. Plus there is virtually no

shift in black level with changes in average picture level

(APL). I confirmed this using the various PLUGE test patterns

provided by the Video Essentials DVD in title 17, chapters 2,

3, 5, and 7. The Video Montage sequence from this same DVD

showed how effectively the G90 held black levels constant to

increase contrast-ratio and reveal shadow details.

I was able to adjust the grayscale color temperature to

exceptional accuracy, 6500K +300/-50K at 7.75 ft-L measured

at the plane of my 1.3 gain screen, which equates to about 10

ft-L for on-axis viewing. The G90 provides a gamma adjust-

ment for individual CRTs that is found on few other projec-

tors. It enables better tracking of the three CRTs and a flatter

grayscale response. I believe I could have improved the

grayscale even further had I had more time. Without even re-

calibrating, I cranked up the light output at the screen plane

to over 14 ft-L and the color temperature only dropped to

6100K. So the projector is capable of much higher light output

than I used for comparison tests.

Despite the excellent grayscale results, I was less

pleased with the color accuracy. The primary reason (pun

intended) was the chromaticity of the green phosphor. It is

somewhat more yellow than the SMPTE C standard green.

(See measurements.) This eliminated the deepest green hues

from the color gamut, slightly desaturated the blue-greens

(cyan), and shifted the purple hues (magenta) toward blue.

The yellower-green can be seen in landscapes and fields

where greener pastures are expected. Skin-tones appeared

slightly pale or colder than normal. If the color temperature

is calibrated slightly more red than normal, the skin-tones

will be corrected and magenta much improved. I found that

a more pleasing picture.

The green phosphor may have been a deliberate choice to

maximize the light output of the projector. The G90 is rated at

1300 peak lumens and 350 ANSI lumens, impressive specs for

a CRT projector. In my testing, the G90 luminance dropped

only 2 percent when going from a small white window to a full

screen of peak white. That is amazing performance and

reflects its superior full-white rating of 500 lumens. The pic-

ture simply won’t dim on the brightest scenes. The white field

uniformity was also exceptional with very little variance in

brightness or color over the screen.

Fan noise on the G90 wasn’t nearly as loud as might be

expected from a projector drawing 1050 watts. I measured 51

dB “C” weighted, at three feet from the unit. The fan noise is

not high-pitched, but has a rushing-air sound that is often

masked by the music and dialog in a movie. It may be accept-

able in a ceiling-mount application without additional attenu-

ation, but I wasn’t able to experience that.

The Sony G90 includes a built-in video

upconverter that converts NTSC formats from

480i (active lines) to 960i interlaced video. Sony

calls its process Digital Reality Creation, or DRC.

It uses pattern matching in look-up tables to do

the conversion. Conventional line doublers or quadruplers

use entirely different processes to create 480p and 960p pro-

gressive video. I used the DRC to watch live basketball games

and DVD movies. Video-camera sources, like the basketball

game, will create some artifacts on any type of upconverter. I

found the artifacts on Sony’s unique DRC system to look more

artificial, dare I say digital, than other techniques. Artifacts

sometimes have a pixellated appearance. It comes down to

matter of preference, but I’m more accustomed and comfort-

able with the twitter artifacts of conventional line-doublers

and quadruplers. On movies the DRC did a better job but

couldn’t match the complete absence of deinterlacing arti-

facts from upconverters that use inverse-telecine processing.

But the DRC feature is included standard with the G90 and a

high-quality quadrupler will approach $20,000.

I used PBS broadcasts to evaluate HDTV on the G90. This

was where it really excelled. Projectors without 9-inch CRTs

simply don’t have enough resolution to fully display the hori-

zontal and static vertical resolution of 1080i signals. The G90

has what it takes. HDTV on 7- and 8-inch CRT projectors like

the Runco DTV-930 can look wonderful, but on the G90 the

picture achieves an astonishing clarity. PBS has many air-

borne sequences flying across agricultural and urban land-

scapes that are so clear that you will feel like you are actual-

ly skimming the tree tops and peering into office building win-

dows. A ride in a raft down the mighty Colorado river may

convince you that it might be better to watch on the G90 than

to actual participate. After sitting glued to my chair watching

this HDTV demo material several times for more than hour, I

can sing praises about the HDTV format and the incredible

resolution and 3-dimensionality of the G90 picture. It rivals

the best film presentations that I have seen at a well-main-

tained cinema. Sadly, few people will actually get to enjoy this

experience.

Summary

The Sony VPH-G90U will produce stunning picture resolution,

surpassing the definition, contrast, and image depth of 8” or

smaller CRT projectors. It is one of the very few CRT projec-

tors, or display devices of any kind, capable of producing

HDTV’s available resolution. Audition it when you are select-

ing from among the ultimate home-theater projectors.

M a n u f a c t u r e r I n f o r m a t i o n

SONY VPH-G90U MULTISCAN PROJECTOR

Sony Electronics Inc

1 Sony Drive

Park Ridge, New Jersey 07656

Phone: (201) 930-1000

www.sony.com

Source: Manufacturer Loan

S/N: 2000039

Price: $35,000

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Sony G90 manual Performance, Summary