In the Black

Joel Brinkley's recent comments on black level issues with the new digital video displays was right on the mark for flat panel displays, but things are looking up, at least a little, with front and rear projection sets. I'm currently working on reviews of two new models, the front projection Sony VPL-VW100 SXRD projector and the Hewlett-Packard md5880n DLP. Both of these are 1080p displays—though only the HP will accept 1080p through its HDMI inputs.

But with all of the hullabaloo about 1080p, the most interesting feature on both displays is their implementation of an auto or dynamic iris. Those who have been following our reviews know what a dynamic iris is, and what it offers, but others may be puzzled by what appears to be a mechanical band-aid for a seemingly intractable problem.

Digital sets, at least to date, have had trouble rendering true black because their light source, unlike a CRT display, is always on whenever the set is in operation. (Technically, of course, there is always some voltage on a CRT when it's powered, but the amount of light this produces on the screen when reproducing black, in a well-designed set, is usually miniscule.) A flat-panel LCD requires a backlight—usually some sort of fluorescent, though LEDs have been researched as a possible replacement, largely because they offer better color. (At least one Sony LCD display with LED backlighting has been marketed in Japan, but not here as yet. And manufacturers are looking into various ways to modulate both fluorescent and LED backlighting for better blacks.) Plasmas need to be kept in a primed state for reliable operation, which results in a low-level glow on the screen even when the video source is a full black field. And projection sets of all descriptions use a projection lamp.

All such displays are able to deflect or block the light source when they display very dark scenes, but they need to do better if they are to render genuinely inky blacks. What is needed is a way to either turn off the light source or block it completely when it's not required.

Rear projection sets using LCD, LCoS, or DLP imaging elements are known in the industry as microdisplays, not because they're tiny in size, but because they use a small imaging chip or chips together with a bright projection lamp. Combine the stray light from that always-on lamp with the high gain screens that rear projector manufacturers use to achieve that searing, showroom brightness they are addicted to, and you have a recipe for mediocre blacks.

Enter the dynamic iris, marketed under various names (Sony calls their version the Advanced Iris, HP uses DynamicBlack, a Texas Instruments trademark you'll see on new rear projection DLPs from many manufacturers). It literally responds to the video source on an instant-by-instant basis. If the scene is bright, it opens up. If it's dark, it closes down to make the blacks even darker.

The automatic iris might seem like the proverbial bumblebee that can't fly (though I recently heard that the scientific community has decided that it can). But it works. While there is some unevenness to the black field in both the sets mentioned here (slightly lighter in some areas than in others—in the case of the HP, this almost certainly comes from internal reflections), this should be solvable at the design end. And even with this limitation, the admirably deep blacks in both sets do produce consistently rich, punchy images from a good source.

Sony's VPL-VW100 SXRD, in particular, now produces deeper blacks and better contrast than the company's upscale Qualia 004. The latter is brighter, so it can drive a larger screen. And it has a number of other unique features like lens options. But it lacks the auto iris feature, and at three times the cost of the new SXRD projector I'd be very surprised if an upgrade isn't in the works to keep it a true flagship.

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COMMENTS
SteveG's picture

Greg Rogers's extensive review of the Sony VPL-VW100 says that it will do 1080p over HDMI.

Glenn's picture

Regarding the last sentence, I thought I read somewhere that Sony will no longer produce the upscale Qualia line - or maybe that only applied to the RPTV implementation (the 006)?

Jason Cooper's picture

Hey Glenn, i read the same thing. You would think that the VPL-VW100 would take 1080p on its HDMI input because the new PS3 outputs 1080p on its HDMI output. On a japanese website i read (or tried to), that Sony's new model of their $3500 LCD projector accepts 1080p and has smaller LCD chips. TJN- have you heard anything about the new version of their LCD projector?

Jason Cooper's picture

I can't remember what search engine I used to find that japanese website, but I think the new model number is VPL-60 as the replacement for the VPL-51.

Tom Norton's picture

The new VPL-VW100 will accept 1080p at its HDMI and, according to the manual, DVI inputs. Yes, the word is that the most of the Qualia line is defunct, but that doesn't mean the Qualia 004--or an updated version--won't still be available, perhaps with a new model designation. I hear rumors about a new LCD projector from Sony, too. That wouldn't be a big surprise; the company seems to come out with a new LCD projector every year. But there would be little benefit to its accepting 1080p if the projector's native resolution is 720p--except to sell more PlayStation3s. All will be clear come CES, which is only 3 weeks away. And check the website this coming week for my review of the VPL-VW100--at least Part I. Part II, which will cover color calibration, color measurements, and additional observations, will come later in Jan uary--after our Photo Research Colorimeter gets out of the shop!

SteveG's picture

Tom, you now acknowledge that "[t]he new VPL-VW100 will accept 1080p at its HDMI." Then why not change the sentence in your post saying this: "Both of these are 1080p displays?though only the HP will accept 1080p through its HDMI inputs."

Scott yow's picture

Just to confirm the 1080p comments.. I own a VPL-VW100 and hooked up my powerbook computer to the DVI input. I set my powerbook computer to 1920x1080/60P and the display worked flawlessly.. i assume this would be the same as 1080p coming from any other source...

Fabio Mattos's picture

Is the Sony VPL-VW100 a better projector than a Sharp 12.000 markII?

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