Category: Product Reviews

Useful Gadgets: RCA DMT336R Mobile DTV/ATSC Pocket TV

It’s hard to believe it’s been just 13 years since the digital TV transition started in 1998 when TV stations WFAA and WRAL first signed on the air.

Back then, ‘watching digital TV’ meant shelling out a couple thousand dollars for a large, energy-guzzling converter box and experimenting with different antennas to try and pull in the signals, which (more often than not) dropped out or froze up.

Fast-forward to 2011: The DTV transition has been history for two years. Every new TV has a built-in ATSC tuner, and the adaptive equalizers in that tuner work so well that signal drop-out from fading and multipath is mostly an unpleasant memory. In fact, ATSC set-top receivers are mostly a memory now, given that you can a new LCD or plasma digital TV for about $10 per diagonal inch.

Even computers can join in the fun, thanks to the latest generation of ‘plug and play’ USB stick tuners from companies like Hauppauge that let you use your laptop or desktop as a fully-featured DVR. Just add an antenna, and you’re ready to go.

Along the way, several manufacturers found the time to bring out some models of portable digital TVs. This product category was pretty thin two years ago, but now there are several brands to choose from, among them the familiar white dogs of RCA (now owned by Audiovox). At the June CES Summer Line Show, RCA unveiled a bevy of portable digital TVs, several of which also receive the nascent MH (mobile handheld) DTV service.

The DMT336R falls into that category. It has a 3.5″ screen, runs for over 2 hours on a single charge, and does an excellent job pulling in both MH and regular over-the-air ATSC broadcasts.

WHAT’S IN THE BOX

There’s not much to the DMT336R. It’s a little bigger than a digital camera, and features a 4:3 TFT LCD screen. (Why RCA didn’t use a widescreen aspect ratio for the LCD remains a mystery.) It has a power button on the side, just above the 5V power jack for recharging the internal battery pack, which is supposed to deliver three hours of viewing time. (It comes close!)

On the opposite side of the case are three connectors. The first is a SMB-type jack for an external antenna. (RCA didn’t provide an adapter from this connector for the review.) There’s also the usual composite video output connection with stereo audio, connected through a mini AV jack. You can also plug in a pair of headphones through a separate audio output jack.

The upper left of the TV housing hides a telescoping 10″ antenna, which can be rotated in any direction. That’s plenty long enough for UHF TV reception, but a tad short for VHF. Even so, if you have enough signal strength at your location, you’ll haul in high-band VHF DTV stations (channels 7-13) just fine.

For such a small TV, the menu is pretty loaded. ATSC and MH programs are tuned separately; you have to access different menus to scan for and select channels from each service. The main reason for that is the ATSC over-the-air standard uses MPEG2 digital video, while the MH service uses MPEG4.

Even though the LCD screen is 4:3, you can select a 16:9 aspect ratio for HD channels. You’ll see black bars above and below the image (also known as “letterboxing”). But you should be aware that most HDTV programs are composed to favor a 4:3 ‘safe area’ so you’ll still see the important stuff even if you opt to watch in 4:3 mode. There are two other aspect ratio settings that allow a partial zoom into the letterboxed image and a setting that takes a ‘center cut’ of the widescreen image.

When tuning in MH services, it takes a few seconds for an active channel to lock up. In the Philadelphia area, only WCAU (digital 10.1) was broadcasting MH when I tested the DMT336R. The long lock-up is due to the massive amounts of Forward Error Correction (FEC) used in the MH service. It’s what keeps the signal present even when you are watching MH TV in a moving car, bus, train, or bicycle. (Wait – how do you watch TV on a bicycle?) You also can watch MH while walking, or in a sedan chair, or in a kayak, or while skiing.  (OK, now I’m just being silly…)

For MH and ATSC reception, we recommend pepperoni pizza and a nice Sauvignon Blanc!

HOW IT TESTED

I’ve tried the DMT336R in a few locations, most of them stationary. In mid-July, I visited John Turner of Turner Engineering at home, w-a-y up in the hills of northern New Jersey. The elevation was about 700 feet and we had a line-of-sight path to New York City.

Not surprisingly, the DMT336R pulled in all of the available UHF stations, along with high-band VHF channels 7, 11, and 13. Reception on each channel was rock-steady using the internal whip antenna, although the position of the antenna was somewhat changed for a few channels. I also identified and pulled in MH broadcasts from WNBC, ION, and Telemunco. All of that error correction introduces lots of latency – it can take 5-6 seconds to lock up an MH broadcast, so don’t expect fast channel changes in this mode. But you will be amazed at how stable an MH signal is once you’re watching it, even if you move the TV around.

During these tests, John took out an older Eviant T7 portable ATSC receiver and we did a side-by side comparison. The DMT336R was clearly more sensitive on weaker ATSC signals, and that’s probably because its adaptive equalizer is at least Gen 6. We also watched a Yankees game on WWOR-9 while enjoying pizza and a bottle of wine, and the battery held out for almost 3 hours. The internal audio isn’t very powerful (900 milliwatts) – it’s loud enough in a quiet room or with headphones, but will be hard to pick up in public spaces or out on your boat. So plan on using a pair of headphones while traveling.

My second round of tests were at home, using my rooftop antenna and the built-in whip. I pulled in all of the Philly ATSC stations, plus a single MH service on WCAU (NBC). My particular location isn’t favorable for indoor DTV reception of any kind, save for megapower DTV station WFMZ in Allentown, PA (channel 46). So a powered antenna is a big help. Still, with WFMZ coming in, I could wander around the house and up and down stairs and still hold the signal 80% of the time. Pretty impressive performance!

Did I mention that the DMT336R also contains an FM radio? Just plug in a set of headphones and tune away – the headphone wires double as the FM antenna.

There is only a two-year difference between the receiver technology in the Eviant T7 and RCA's DMT336R, but that made for quite a difference in my tests.

THE WRAP-UP

Portable digital TVs have become so inexpensive that it makes plenty of sense to have a few around the house, especially if you suffer from frequent power outages and severe weather. Some portable DTV manufacturers have referred to these gadgets as “hurricane TVs” for that reason.

You can also catch your local sports team in action with the DMT336R. Want to sit on your boat on a Sunday afternoon and catch an NFL game? Or the Saturday baseball game of the week? Here’s one way to do it. There are also plenty of ‘retro’ TV networks carried as secondary DTV channels these days (like This TV) that are fun to watch when traveling. With over 1700 digital TV stations broadcasting across the country, you’ll find something to watch.

The DMT336R delivers the goods. Yes, it could use a more powerful speaker, and yes, it should have come with a widescreen display. But the DMT336R tunes ATSC and MH channels like a champ and costs only $169 (retail), and it’s a low-cost way to access the new MH broadcast services.

You can find out more about the full line of RCA portable digital TVs at www.getmyelectronics.com.

Product Review: Mitsubishi HC9000 Diamond 3D Projector

While 3D TVs have been available for over a year, the first crop of 3D front projectors are shipping now. The models I’m aware of use either digital light processing (DLP) or liquid crystal on silicon (LCoS) imaging technologies, and all of them are engineered to operate with active shutter glasses, with the exception of LG’s $15,000 CF3D, which works with passive eyewear.

Mitsubishi’s HC9000D has been in development for the better part of a year, and I had the chance to see it in the prototype stage a few times prior to this review. Those earlier versions were underpowered, making the 3D footage they projected unusually dark.

Now, Mitsubishi has started shipping a fully-powered chassis with some interesting bells and whistles inside. It comes with power zoom, focus, and lens shift, plus multi-step gamma correction and a two-position IR emitter for synchronizing its active shutter glasses.

Figure 1 – The HC9000D is definitely a ‘looker!’

OUT OF THE BOX

This is not a small projector, nor is it particularly light at 32 pounds. But it does have that cool gloss black finish that disappears into the darkness, plus an aerodynamic housing with all of the connectors along the left side, and not in the back.

The imaging engine for the HC9000D may be a surprise to you: It uses three .61” SXRD LCoS chips, just like the previously-mentioned LG CF3D and of course, both of Sony’s 3D front projector offerings. This is Mitsubishi’s first foray into reflective imaging, and LCoS offers a much lower cost than 3-chip DLP engines.

3D projectors need lots of light to overcome all of the polarization losses in active shutter glasses, so Mits has equipped the HC9000D with a 230-watt short-arc lamp. The supplied zoom lens has a ratio of 1.8:1, adequate for any home theater set-up as it easily lit up my Da-Lite Affinity 92” screen at a distance of 12 feet.

The input connectors include a pair of HDMI 1.4a inputs that also support ten different standard digital computer resolutions, and there’s also an analog VGA PC input connector for everything from 640×480 to 1080p/60. Mitsubishi has also provided a single component video (YPbPr) input, plus composite and S-video jacks. (Question: Why are manufacturers still supporting composite video on high-end 1080p projectors?)

The interface panel is rounded out by a pair of 12V triggers for powered screens and anamorphic lens adapters, an RS-232 jack for remote control, and another DIN jack that connects to the EY-3D-EMT1 IR emitter through a short (1 meter) or long (15 meter) cable. The emitter can be attached to the lower front panel of the projector, or positioned under your projection screen.

The supplied remote control is identical in function to all previous Mits remotes (I inadvertently turned on my Mits HC6000 a few times with it), except that it has a black housing. You can directly access any input, jump to preset picture modes, operate the powered lens functions, and step through the iris settings. The only exception is that the STANDBY button now toggles between 2D and 3D display modes.

MENUS AND ADJUSTMENTS

Mitsubishi 3LCD projectors are known for high image quality and part of the reason is the detailed menus provided for in-depth calibrations. That protocol continues with the LCoS-powered HC9000D. Four different picture preset modes (Cinema, Video, 3D, Dynamic) are provided for viewing, along with three USER memory slots.

Gamma correction is also possible through five presets (Cinema, 2.0, 2.1, 2.2, 3D, and USER), and the USER gamma adjustments offer detailed adjustments of white, red, green, and blue at 15 grayscale steps. That is a tremendous amount of tweaking at your fingertips, if you are that fanatical about precise gamma response.

Color temperature and white balance adjustments are also available for each USER mode, or you can select from one of six presets, including 5800K, 6000K, and 6500K. None of these are completely accurate, but will get you into the ballpark. There are also a set of color management controls for all six primaries that I suggest you avoid playing with, as they don’t exactly work as intended in their current implementation.

The menu complement is rounded out with three different levels of black set-up (0, 3.75, and 7.5 IRE), a ‘cinema filter,’ 3:2 frame rate conversion or ‘true’ (native) frame rate selections, and various adjustments for noise reduction and detail enhancement. The former will soften the image to hide digital noise artifacts, while the latter may enhance edge transitions too much. I’d leave ‘em both off if possible.

The HC9000D also has image warping software (referred to in the owner’s manual as ‘Anyplace’ control) built-in. It lets you re-map the pixels on a projected image to correct for off-axis projection, such as a severe high and wide angle. While it works quite well, it does impact image resolution as it decimates pixels to correct for trapezoidal distortion. (It can also fix lens distortions like barreling and pincushioning.)

You are much better off mounting the projector as close to the optical centerline of the screen as possible, and using the lens shift controls to move the image into position. Try to avoid any adjustments that manipulate pixels to correct for geometry!

The HDMI inputs have their own sets of tweaks. You can manually select the HDMI color depth (4:2:2, 4:4:4, or RGB), or let the projector configure it for you. There are also four different HDMI inputs modes – Auto, Standard, Enhanced, and Super White.

It’s best to leave this setting in Auto, as it will pick the correct color bit depth for each connected input. Enhanced is usually selected for PC input connections, but I have no idea what ‘Super White’ is intended to do: The manual just says, “Select when solid white occurs.” Any guesses?

There are also a few useful 3D image adjustments. The only 3D mode that is detected automatically by the HC9000D is the Blu-ray 1080p/24 frame-packing format, so called because it packs both left eye and right eye video into a single BD frame with 45 pixels of blanking for a total of 1920×2205 pixels. On the other hand, the so-called ‘frame compatible’ 3D formats (also known as ‘half-resolution’ formats) must be selected manually in the 3D menu, and include top+bottom (720p) and side-by-side (1080i).

You can compensate for light attenuation through polarization losses by boosting projector brightness in five steps, with 5.0 being the default setting. The sync pulse for active shutter glasses can also be reversed if needed in this menu. Normally, you should not need to play with either control (and as you’ll find out, a brighter screen will do you more good than the 3D brightness compensation settings!).

The last control I should point out is the ever-present Iris adjustment. Dynamic iris controls are de rigueur for LCD and LCoS projectors to drop black levels and improve contrast on low-level video content. I have never liked these adjustments because of the non-linear effect they have on gamma curves, and prefer to leave them off and just work with whatever dynamic range the projector manufacturer brought to the table – which isn’t as bad as you might think most of the time.

If you must use the iris settings, you have four different presets (Open, 3, 2, and 1), plus 18 steps of irising in the User menu. My advice? Set your black levels correctly and adjust the contrast for best dynamic range, and just live with it. In 2D mode, the black levels may be a bit higher than you’d want, but in 3D mode, you won’t see them anyway with the glasses on.

ON THE TEST BENCH: 2D

For my tests, I used a combination of SpectraCal’s CalMan V4.4 software and ColorFacts 7.5 to take all readings through Spyder 2 and Eye One Pro sensors. All of my calibrations were done in 2D mode, as I was most interested to see what the projector did to these settings when switched into 3D mode.

All 2D test patterns were generated by an AccuPel HDG4000, while my 3D test patterns were custom-created in Photoshop and played back @ 1280×720 resolution from a Toshiba M645 laptop computer, using the top+bottom frame compatible format. Additional 3D content came from Samsung’s Blu-ray test disc and 3D Blu-ray movie clips from Avatar and How to Train Your Dragon, played back on a Samsung BD-C6900.

You will be surprised at how little tweaking you’ll need to do to get a stable grayscale out of the HC9000D. After minimal calibration, I measured 2D brightness at 635 lumens with a center color temperature of 6542 degrees. That color temperature reading varied by a maximum of just 230 degrees over nine points of measurement. So far, so good!

Brightness uniformity was lower than I expected at 69% to the average corner from center, and 55% to the worst corner. That’s bordering on hot-spot territory, as 50% is a drop of one full f-stop in brightness. Contrast measurements were much better than you’d expect with the iris off, coming in at 279:1 ANSI (average) and 538:1 peak. While those numbers aren’t as impressive as what JVC’s achieved with their wire grid dichroic design, they are still respectable for any other LCoS projector.

I mentioned earlier that Mitsubishi always does a superb job with grayscale and color temperature performance. Figure 2 shows an almost-perfect 2.3 gamma curve after calibration that’s as good as any I’ve ever seen on the best projectors. (And it was measured with the iris disabled.)

The secret? Very tight tracking of red, green, and blue levels at each luminance measurement. You can see just how tight those levels track in Figure 3, which is the RGB histogram for the target color temperature setting of 6500 Kelvin.

Figure 2 – The HC9000D produces a nearly-perfect 2.3 gamma curve after calibration.

Figure 3 – This RGB histogram shows tight tracking of red, green, and blue across the entire grayscale.

The HC9000D has a ‘ginormous’ color gamut, which (unfortunately) cannot be dialed back accurately. That means the colors you’ll see off Blu-ray discs and other HD content will be over-saturated. The color management controls will not help you here – de-saturating a color will result in incorrect display of other secondary colors.

The correct approach is to set the exact color coordinates at the factory for RGB and CMY, based on the standard used to master the content being viewed, something very few projector manufacturers bother to do. Figures 4a-b shows the full color gamut of the projector compared to the BT.709 HDTV gamut and P3 digital cinema gamut.

Figure 4a – The HC9000D’s mapped color gamut, compared to the BT.709 HDTV color space.

Figure 4b – And here’s how the HC9000D’s color gamut compares to the P3 digital cinema color space.

ON THE TEST BENCH: 3D

All well and good – the HC9000D is a top-notch 2D projector – but what happens in 3D mode? For starters, let’s see what happens when switching from 2D mode to 3D mode with glasses off and on.

To measure the changes in brightness, I placed a Minolta CL200 directly in front of my projection screen to take an incident light reading from the projector for this test. I started with a baseline (glassless) reading of 1124 lux and a measured color temperature of 6190K – a bit on the warm side. With 3D mode enabled on the projector, but no glasses in place, the readings changed to 1137 lux (3D brightness @ 5.0) and 6093K.

After positioning Mitsubishi’s active shutter glasses in front of the CL200’s sensor, brightness readings dropped to 419 lux with a color temperature of 6576K. Finally, I turned the glasses on, and saw brightness drop to 146 lux while the measured color temperature soared to 8529K. (Switching the lamp from its normal setting into HIGH mode increased brightness slightly to 66 lux.)

That’s quite a decrease! Comparing the final 3D reading with glasses to the calibrated 2D reading without glasses, the amount of light that finally makes it to your eyes has decreased by about 87%

So, what’s the solution? You will need a higher-gain screen to enjoy 3D images from the HC9000D, as it’s just not bright enough for viewing on low-gain screens with active shutter glasses – at least, not at the projection distance I use. I dusted off an older 82” Vutec SilverStar (6.0 gain) screen, and it made a world of difference with the HC9000D.

Here’s the conundrum: A high-gain screen doesn’t match up well to the projector’s 2D mode, as it will elevate black levels. Does that suggest you’ll need two screens? Maybe not, as Stewart Filmscreens just announced a combination 2D/3D screen that’s supposedly optimized for both modes. (They call it “5D” – I kid you not!)

IMAGE QUALITY

2D image quality is top-notch, as you’d expect with a projector using an HQV Reon processor. The adjustable frame rates are used to convert 24 fps filmed content to 96 Hz (quad refresh), while 60 Hz video is doubled to 120 Hz. Scaling of 720p content to 1080p is seamless and de-interlacing of 1080i channels showed absolutely no motion errors. The projector’s dynamic range is excellent (within the limits of its black levels) and my only complaint is that colors pop too much, for reasons I explained earlier.

You could be very happy just running this projector in 2D mode. In 3D mode, it’s a different story. Most of the content I looked at on my Affinity screen was too dark when viewed in 3D mode and exhibited desaturated colors with low contrast.

The Vutec gain screen helped considerably, but this projector needs to be cranking out at least 300 – 400 3D lumens after calibration to work with my screen type, size, and projection throw. If you reverse-engineer the numbers, that means almost 3000 lumens in calibrated 2D mode.

The best 3D scenes were observed with the daytime flying sequences in Dragon and the final attack sequences in Avatar. On the Vutec SilverStar screen, they punched up considerably with improved color saturation, and the viewing experience was quite enjoyable. The 24-96 fps frame rate conversion provides a smooth, bright image with absolutely zero flicker.

One problem I noticed was crosstalk in each lens. This popped up when the glasses were tilted even slightly, with the effect more pronounced in high-contrast scenes. For 3D to present correctly; crosstalk in the glasses has to be kept to a minimum. Otherwise, you will begin to feel eyestrain and may develop a headache after sustained viewing.

For comparison, Sony’s 3D active shutter glasses suffer from crosstalk problems because only one polarizer is used, while Samsung and Panasonic glasses use two polarizers and are much better at suppressing crosstalk. The Mitsubishi glasses also use dual polarizers, but their ‘extinction ratio’ isn’t as good as I would have expected. Figures 5a – 5d show sample 3D images where crosstalk is strongly evident and not quite as evident.

Figure 5a – This 3D text chart shows crosstalk (ghost images) around the letters and vertical lines.

Figure 5b – A ghost image of the center circle can be seen clearly in this photo.

Figure 5c – Crosstalk isn’t as evident when watching 3D movies, although I noticed it in this scene from How to Train Your Dragon.  (Image © 2010 Dreamworks Animation)

 

Figure 5d – Subtle ghost images were seen along the edges of the mountains and the dragon’s wings.  (Image © 2010 Dreamworks Animation)

You will clearly see double images in the test patterns, but the ghosting isn’t quite as apparent with the stills from Dragon. But it is there, along the jagged rocky cliffs and other background objects. It all depends on the angle of your head – if you tilt your head to either side, the effect becomes more pronounced. Ghosting is readily apparent with credits and other high-contrast text and symbols.

CONCLUSIONS

Mitsubishi’s HC9000D is a top-notch 2D projector, but underpowered for 3D with low-gain screens. It calibrates quickly and performs nicely, but those calibrations will shift noticeably when viewing with 3D glasses. You’ll definitely need a gain screen with this projector for 3D content, and it might be a good idea to choose one that has a slightly warm color temperature that will offset the higher color temperature in 3D mode.

More horsepower under the hood would help. As I mentioned earlier, something in the neighborhood of 3000 lumens would be required to (a) perform a full 2D calibration and (b) provide enough illumination in 3D mode to low-gain (1.0 to 1.3) screens in the 82-inch to 102-inch range, assuming  a projection distance of 10 – 12 feet.

However, if you are sitting closer to a smaller screen, then you will be in better shape: The HC9000’s measured light output after calibration should be adequate for 3D viewing on a 72-inch screen at a distance of 6 to 8 feet, as you will wind up with 3x to 4x brighter images. And you DO want to sit closer to 3D screens to get the maximum impact: My recommended seating distance is 1x to 1.3x the screen diagonal measurement. That will make the 3D images fill 50% or more of your field of view, and give you that theater-like immersive experience!

Product Review: Samsung PN50C8000 3D Plasma TV

Back in October, I had some time to test drive Samsung’s UN46C7000 3D LCD TV. Although it had many strong points, I’m just not a big fan of 3D over LCD, mostly because of the black level and viewing angle issues.

I figured plasma should be a better match to 3D, seeing as that it had the widest viewing angle, bright and contrasty colors, and no issues with the physics of light waves (when you watch 3D on an LCD TV, you are looking through as many as four different polarizers).

Samsung’s PN50C8000 ($2,599 list) showed up in early January for a round of testing and is one of the company’s top-line 3D plasma TVs. I paired it with the BD-C6800 Blu-ray player (MSRP $250), along with a copy of How to Train Your Dragon in 3D. (Thank God, as I was burned out after watching Monsters vs. Aliens umpteen-million times!)

 

OUT OF THE BOX

The PN50C8000 is remarkably similar to the UN46C7000 in design, except that it gets a much sturdier base. Once again, the finish around the bezel and on the stand is a shiny silvery color, while I still prefer darker bezels that are less distracting.

I will say that this is extremely lightweight plasma, tipping the scales at 63 pounds with the stand. It wasn’t that long ago that 50-inch plasmas weighed over 100 pounds, and that was without a stand! 63 pounds is well inside LCD TV country, so if you were hesitant to buy a plasma TV because of its weight, let that put your concerns to rest.

Samsung has provided plenty of input connections on this TV. There are four HDMI inputs, all of them version 1.4a compatible. Input #1 also supports connections to a personal computer, while Input #2 is the audio return channel (ARC) connection for an external AV receiver.

There’s also a single analog component video (YPbPr) connection, the ‘Y’ (luminance) connection of which doubles as a composite video jack. Unlike the UN46C7000, the PN50C8000 uses full-sized RCA jacks for these two inputs. But there’s a catch – you need to chase down small-diameter RCA connectors to use these connections as they are so close to the rear wall of the plasma TV. The provided F-style RF connector is the normal, threaded type, so leave your adapters at home. There’s enough space around it to screw in a normal F plug.

 

Here's what the back end of the PN50C8000 looks like. All of the connectors are on the right side.

 

All of the HDMI connections support CEC, so when you turn on your Blu-ray player, the TV also powers up and switches to that input automatically. Samsung’s also included a Toslink output jack so you can feed digital audio from TV programs to your AV receiver, but you’ll need to come up with the cable. HDMI input #2 will also provide an audio return path to your receiver.

MENUS AND ADJUSTMENTS

Menu adjustments are very similar to those on the UN46C700, so I’ve retained those descriptions from my earlier review of the UN46C7000.

Samsung’s menus are easy to navigate.  There are six image presets, labeled Dynamic, Standard, Relax, Movie, ISF Day, and ISF Night. Stay away from Dynamic mode, as the pictures are extremely bright and over-enhanced. Standard, Natural, and Movie modes all work well for everyday viewing, but if you are into calibration, you’ll need to use Movie mode. You’ll also find it to be one of the brighter modes. ISF Day and Night modes can’t be adjusted by the average user; only a calibrator can tweak those.

You can select from four different color temperature settings, five different aspect ratio settings, and a host of ‘green’ energy setting modes called Eco Solution. Seeing that this is a plasma TV, you can also adjust cell brightness (separate from black level and contrast) at levels from 0 to 20. Cell brightness has to do with how hard the plasma pixel are driven, and you will see a big change in overall brightness playing with this control. (I set it at 15.)

There is also a screen protection sub-menu that activates pixel orbiting at preset intervals. Or, you can turn on a scrolling feature to rid the screen of any ‘stuck’ images. (It’s just like an electronic Sham-Wow!)

There are other image ‘enhancements’ that Samsung has included, including three different black levels, three settings for dynamic contrast, and a shadow detail enhance/reduce adjustment. My advice is to leave them all off, particularly Black Tone and Auto Contrast.  Generally, these settings mess up gamma performance, and if you are into quality pictures, that’s a must to avoid.

For calibrators, there are two Expert Patterns (grayscale and color) for basic brightness, contrast, saturation, and hue calibrations. You can also select red, green, and blue-only modes, as well as Auto, Native, and Custom color spaces. The Custom mode lets you define your own x,y coordinates for primaries.

For color temperature calibration, Samsung provides two-point and ten-point RGB gain and offset adjustments. The theory is to do most of the calibration in two-point mode, then go back through a multi-step grayscale in ten-point mode for fine-tuning. Other adjustments include Flesh Tone enhance (leave it off), xvYCC mode (leave it off as well, no one currently supports extended color in packaged content), and the usual edge enhancement (peaking) stuff. As I’ve said before, HDTV doesn’t need enhancement!

There are a couple of noise filters that have some effect on image quality. The MPEG noise filter attempts to use low-pass filtering to get rid of mosquito noise and macroblock (excessive compression) artifacts. Be warned that low-pass filtering softens high-frequency image detail, so go easy on these controls. For HD programs, you probably won’t need them, unless you happen to be one of those unfortunate subscribers to U-Verse (720p and 1080i HDTV @ 5 Mb/s looks pretty awful).

Samsung’s Auto Motion Plus corrects for 24-frame judder by pulling the frame rate up to multiples of 60 Hz. In the case of the PN50C8000, the corrected frame rate is probably close to 240 Hz, the same speed at which it operates in 3D mode. What this actually does to images is to make filmed content look like it is live, or shot at video rates.

The result is a very smooth presentation, free of flicker and judder, but it just doesn’t look the same as a movie. The motivation behind Auto Motion Plus (and every other TV manufacturers implementation of it) is to get rid of motion blur and smearing, something that all LCD TVs suffer from to various degrees. Try it – you may like it, you may hate it.

I’d be remiss here in not discussing any of the connected Samsung apps, which let you stream movies and TV shows directly from YouTube, Netflix, and Hulu Plus. While this is a handy feature, don’t expect picture quality to come anywhere close to that of a Blu-ray disc, or even an HDTV channel. Watching Netflix movies over the Internet is more akin to looking at VHS tapes, or composite video from DVDs – the resolution just isn’t there. So use these features more for their convenience than their quality. ESPN updates are also accessible, and if you are addicted to ‘tweeting’ and ‘friending,’ you also have one-touch access to Twitter and Facebook.

3D MENUS

Samsung 3D TVs automatically recognize the HDMI v1.4a frame packing format. This format, which delivers movies at 1920x1080p @24 Hz resolution, is so unique that if you start playing a 3D Blu-ray disc, the PN50C8000 will automatically switch into 3D mode – no further adjustments required.

The two frame-compatible 3D formats (1080i side-by-side and 720p top+bottom) require some help from you to be shown correctly. Once you’ve established that you are indeed seeing the unprocessed 720p or 1080i 3D program from your content provider, go into the PN50C8000’s 3D menu and turn 3D mode ON.

Your will then be presented with a menu of 3D frame compatible formats to choose from, including side by side (1080i) and top & bottom (720p), plus other formats. Aside from frame packing and side-by-side/top & bottom, you are most likely to run into the checkerboard format when playing back 3D games and other non-standard media.

Samsung also has 2D to 3D conversion algorithm built-in to all of their 3D TVs. My advice is not to try and add synthetic 3D effects to everyday TV shows and movies, but stick with content that has been specifically formatted for 3D.

ON THE TEST BENCH

Unlike the UN46C7000 and its persistent auto-dimming feature, I was able to tune up the PN50C8000 quite nicely with basic menu adjustments, plus some assistance from the 10-point white balance menu. I used AccuPel HDG4000 test patterns and ColorFacts 7.5 to perform the measurements.

After my best calibration, I measured brightness in Movie mode at 80 nits (23.4 foot-Lamberts). That number didn’t vary by much, ranging from 73 nits in Relax mode to 83 nits in Movie mode with the Cell Light setting at maximum (20). Why so low?

 

After calibration, the PN50C8000 produced this beautiful 2.3 gamma curve.

 

Apparently this plasma TV employs a front-surface vertical polarizing filter to improve black levels and cancel out reflections. It’s an old trick – Pioneer KURO plasma TVs also used it – but it reduces the vertical viewing angle. You can verify this by walking right up to the TV and looking down at the screen; a you get closer, you’ll see image brightness drop off dramatically.

That additional polarizer (or patterned glass filter) reduces overall brightness, too. While 80 nits is plenty at night, it’s a little dim when viewing under high ambient lighting. But there’s only so far you can push image brightness on this TV.

Fortunately, image contrast doesn’t suffer from the additional filtering. ANSI (average) contrast measured 815:1 in Movie mode with cell light set at 15. Boosting cell light ‘to the max’ at 20 kicked that number up to 913:1. Peak contrast in normal cell mode was 939:1, while with maximum cell lighting, it was just shy of 1000:1 (991:1). Black levels measurements were impressive at .09 nits in Movie mode – that’s deep, bro.

White balance uniformity was outstanding. I measured a maximum color temperature shift of 215 degrees Kelvin across a full white field, which is reference monitor performance.  The PN50C8000 also tracks a rock-steady color of gray, varying by just 245 degrees from 20 to 100 IRE.

 

Color temperature tracking on the PN50C8000 is rock steady.

 

Gamma performance is also noteworthy. After some tune-up (and disabling auto contrast and black tone), I was able to come up with an almost-perfect 2.3 gamma curve, which emulates the classic CRT gamma response and provides great low-level shadow detail, except for some pulse-width modulation noise.

The RGB histogram shows why. Red, green, and blue track each other very closely from 20 IRE on up to full white, with most of the variation coming in the blue channel. I’ve seen this erratic blue tracking in Panasonic plasma TVs as well and it’s not anything you can correct easily – outboard color gamut and gamma correction hardware and software would run about $6,000, so don’t lose any sleep over it!

Like most plasma TVs, the PN50C8000 has two much cyan in its green phosphors, pulling the color space towards blue for a brighter image. The yellow and blue coordinates are on the money, while cyan is shifted too much towards blue (predictably) and red is a bit over-saturated when compared to the BT.709 standard gamut for HDTV signals.

 

Hre's how the PN50C8000's color gamut compares to the BT.709 HDTV color space (dark outline).

IMAGE QUALITY

It doesn’t matter whether you are watching 2D or 3D programming, you will find the pictures this TV produces very pleasing to the eye with excellent color shading and contrast. Those attributes come in real handy when viewing 3D content, especially if you are sitting off-axis. Interestingly, my calibration of the PN50C8000 was the brightest, not to mention very accurate. So I didn’t need to switch out of Movie mode to kick some more photons to the 3D glasses.

Watching How to Train Your Dragon in 3D is a real treat. I thought this was the best 3D movie of 2010, and it was evident that a lot of care went into designing and executing the 3D effects. The flying sequences are just amazing, particularly when Hiccup and Toothless the dragon are swooping and skimming above the ocean, dodging and twisting through rock formations and around cliffs.

In fact, I think it actually looked better on this TV than in the theater (Sony SXRD 4K projector and RealD glasses). Just for fun, I set the TV up in the concessions lobby at the Ambler Theater’s annual Oscars Party (Dragon was nominated for best animated feature and best score, two awards it should have walked away with IMHO) for the 400+ attendees to test-drive. Most of them were predictably wowed by the flying sequences in 3D.

As I mentioned in my review of the UN46C7000, the 3D experience using frame compatible formats isn’t quite as impactful as a 3D Blu-ray disc. The latter format has more detail, more contrast punch, and is just a lot more satisfying to watch. Because the two frame-compatible formats are half-resolution, 3D coverage of sports and other programming – even movies – leaves a bit to be desired.

That unusual low gray noise I mentioned appears to be sub-field sampling noise. It’s evident when playing Blu-ray movies in low-level scenes and on  occasions it can be pretty distracting. Panasonic and LG plasma TVs also exhibit this pulse-width modulation (PWM) noise to varying degrees, but I didn’t notice it as quickly as I did on the PN50C8000. Apparently operating in 1080p/24 mode seems to aggravate it; I didn’t notice it much at all while watching prime time programs in the 720p and 1080i formats. If you spot it, make sure the sharpness control is set to near zero and experiment with the MPEG noise reduction, as that can help minimize this artifact.

My only other negative comment is that you will sometimes notice ghost images on the PN50C8000 after even short periods of operation. It doesn’t matter what brightness level you are running, or even if the display is calibrated – the ghost images still appear when you are showing a dark gray to 50% white screen.  What I’m seeing is not burn-in, as you can turn off the TV, turn it back on, play back different content, and observe an entirely different ghost image.

What I would suggest is to ‘wear in’ the TV when you first get it out of the box – leave a full white test pattern on screen for 200 hours, or use the internal scrolling pattern for the same length of time. That will ‘settle down’ the blue phosphors (which naturally age the fastest) and any subsequent calibration should hold nicely for a long time.

CONCLUSION

Samsung’s PN50C8000 is definitely on the cutting edge of plasma TV design. The performance of this TV (aside from the low-level PWM noise) approaches Pioneer’s late, lamented KURO sets. It is a strong performer with excellent color quality, grayscale shading, and color temperature tracking. You’ll have plenty of contrast and deep, rich black levels to enjoy, even if the overall brightness is on the low side for a consumer TV product.

As far as plasma goes, there’s simply nothing better for viewing 3D – no off-axis contrast flattening or color shift, no crosstalk (common on LCD TVs), and if your head isn’t perfectly level, don’t worry – you won’t see any double images. From my perspective, 3D on a plasma TV comes closest to watching 3D on a DLP Cinema projector of any home theater experience so far.

Full specifications and other product information are available here – http://www.samsung.com/us/video/tvs/PN50C8000YFXZA

Current MAP on this TV is $2,299 as of March 8, 2011.

Power consumption tests – Over an 8-hour period, the PN50C8000 consumed an average of 205 watts while in Movie mode with full-screen HD and SD content. Cell light was set to 15 and peak brightness was 85 nits.

Vizio VF551XVT LED LCD HDTV

As prices of flat-screen HDTVs continue to plunge, you can point the finger at one company in particular for influencing that trend: Vizio. The aggressive discounter has become a dominant player in LCD HDTV sales, capturing the #1 position on more than one occasion and sticking it to established stalwarts like Sharp, Sony, and Samsung.

First getting started with wholesale clubs like Costco and Sam’s Club, Vizio is also in Wal-Mart and Sears. Taking a page from Samsung, the company advertises extensively during the fall football season. And its lineup of TVs covers all of the bases from a $200 19” LCD model to three 55-inch 1080p LCD sets, the most expensive of which is $2,199 and the subject of this review.

Vizio’s VF551XVT will naturally get lots of attention for its super-low price. The fact that it has an LED backlight and incorporates 240Hz motion processing will only attract more attention. And yet, its narrow viewing angle impaired the viewing experience for me.

Figure 1. Vizio’s VF551XVT is the company’s first LCD TV to use an LED backlight.

OUT OF THE BOX

The VF551XVT comes ready to play, out of the box. Simply unpack it and find a suitable flat surface to set it on – the stand is attached. (Vizio also offers a white glove delivery service for a few extra dollars.)

You’ll get plenty of inputs, as is usual with Vizio. The rear panel contains four HDMI 1.3 jacks, one of which also comes with analog audio inputs for connection to older DVI-equipped DVD players and set-top boxes. There’s also a component video input, a PC input (VGA jack), and one each composite and S-video jacks with analog audio.

On the left side, you’ll find a fifth HDMI 1.3 connector, plus another component video input and a second composite video input. (Question: Why are manufacturers of large 1080p LCD HDTVs including composite video jacks at all, let alone two of them?)

Figure 2. You won’t lack for connections on this TV. How do five HDMI inputs sound?

An optical Toslink jack on the rear panel provides a digital audio hook-up to an external home theater receiver, and there are also analog stereo audio output jacks. For TV viewing, the VF551XVT includes a single F connector, which can pull in either terrestrial (ATSC) digital and analog TV stations, or analog/digital cable channels that haven’t been encrypted.

Vizio has also included an USB port for listening to and watching a wide range of portable media files, including MPEG4 (H.264 AVC), Windows Media 7/8/9, MPEG2, AAC, MP3, and JPEG still images. These external flash drive connections are actually quite popular with consumer, particularly for showing home video or digital photographs!

REMOTE AND MENUS

The supplied remote is a great design, with just the right number of buttons that are large enough to operated without reading glasses. It’s also backlit for darkened rooms. You can select banks of inputs by pressing one of four smaller buttons and then toggling through the choices.

Figure 3. The remote is stylish and well laid out.

The menus are well designed, and navigation through them is quick and easy. For the average viewer, you can select one of nine factory picture presets, all of which can be altered. The differences between the sports-themed presets (Football, Golf, Basketball, and Baseball) are almost insignificant, and you have to wonder why Vizio included so many. The good news is, you can tweak all of them to your heart’s content.

Vizio has also incorporated a host of image processing adjustments under the Advanced Video sub-menu. For more detailed calibrations, Vizio has included four color temperature presets (Normal, Custom, Cool, and Computer), plus red, green, and blue contrast and brightness adjustments.

Heads up – if you want to calibrate the TV (or have someone else do an ISF calibration), you’ll need to leave all of the image enhancements off, particularly the color enhancement, adaptive luma, and smart dimming – a feature that adjusts the brightness of the image dynamically to improve blacks by controlling blocks of LEDs.

The white LEDs – 960 of them, divided into 80 blocks – can provide instantaneous dimming to lower black levels in dark scenes while raising them in bright scenes. In theory, that should result in very high contrast ratios…except that highlights are also dimmed as black levels drop, and that makes for some screwy gamma curves.

120Hz LCD TVs are pretty commonplace now, but their effectiveness in reducing motion blur is debatable. Vizio has moved to a 240Hz system, deriving that frame rate by a combination of partial black frame insertion with a scanning (switching) LED backlight. The control for it is labeled Smooth Motion, and has three settings, plus off.

The audio menu is pretty conventional, but does include a handy lip sync adjustment to correct for audio latency errors – a technical problem you’d think would be rare, but pops up more often than it should. SRS TruSurround sound is also included in the VF551XVT, as is SRS’ TruVolume peak limiter. This latter processor keeps you from being blasted out of your chair by a loud commercial after a relatively quiet program.

ON THE TEST BENCH

I found most of the factory picture settings for the VF551XVT to be way too bright, and a quick check with my calibration tools confirmed that observation. Factory set brightness modes are in the range of 430 nits, or 126 foot-Lamberts. (That’s tanning lamp territory!) For everyday viewing, you’ll want to crank back the contrast, brightness, and backlight setting considerably to avoid eyestrain. Yes Virginia, there is such a thing as too much brightness…

I selected Normal mode and calibrated the VF551VXT for best dynamic range, a job that is not at all easy since you have both an adjustable backlight and contrast and brightness settings to deal with. Eventually I chose a peak brightness value of 140 nits, which works out to a very-bright 41 foot-Lamberts. The backlight was set right in the middle, at 50.

As I mentioned earlier, all image enhancement or processing settings were turned off for calibration. Even so, it was quite a job to determine what “black” was! With the backlight set too high, “black” is a pretty washed-out gray. Set it too low, and overall image brightness suffers. (After calibration, the lowest average black level I measured was .265 nits, which is about three times higher than a typical plasma TV.)

My initial calibrations resulted in some extremely steep gamma curves measuring close to 3.0. Normal video gamma would be between 2.2 and 2.3, so I had to play with both the brightness control and backlight to find that elusive combination of low grays that gave me a normal gamma, but preserved shadow detail. After several tries, I produced the somewhat inconsistent gamma curve seen in figure 4 – it averages out to a 2.3 value.

Figure 4. Here’s the final gamma curve for the VF551XVT. It’s a little bumpy.

Figure 5. The VF551XVT tracks a given color temperature nicely above 20 IRE.

Contrast measurements were decent. Using a 16-block checkerboard, I measured average (ANSI) contrast at 481:1 and peak contrast within the same test pattern at 589:1. A sequential contrast measurement came to 528:1 – lower than the peak contrast ratio. How is that possible?

Simple – the VF551XVT’s brightness uniformity varies noticeably across a full white test pattern. Taking nine measurements across the screen, you’ll se a variation of about 8% from the highest to lowest reading. Go into the corners, and the difference is as much as 15%.

Color temperature also shifts by quite a bit over that same full white screen. I measured a shift of 634 Kelvin from lowest to highest readings, and that was in two adjacent screen areas. Measured at the center, the VF551XVT tracks a tight grayscale around 6500 Kelvin, as seen in Figure 5.

Now, about the visual “flaw” I mentioned at the start of this review: Like all LCD TVs, the VF551XVT has issues with brightness uniformity over wide viewing angles. On this TV, you will notice that black levels on different parts of the screen increase dramatically with small changes in horizontal and vertical viewing angles, and that’s not good.

The variation in black levels isn’t consistent across the screen. I noticed this immediately while displaying a small area white window test pattern. As I moved my chair left to right from the dead-center “sweet spot”, the opposite screen section started to wash out and become noticeably brighter in areas that should have been black.

The same effect was seen watching nighttime scenes from CSI and Flash Forward – and it was very distracting. With most LCD TVs, as your viewing angle shifts off-axis, the entire screen starts to wash out. Instead, on the VF551XVT, you’ll see “hot” corners, sides, or large portions of the screen as you move slightly off-axis.

To me, that is a major problem as not everyone gets to sit in the best seat in the house. And the best seat has a small viewing “sweet spot” of about 30 degrees. Move beyond that, and you’ll clearly see the changes in black and low gray levels – something you will never see on a plasma TV. (Too bad Vizio stopped selling those!)

I’ll conclude my test bench results by stating that the VF551XVT produces a color gamut that is somewhat larger than the BT.709 standard HDTV gamut, with blue, red, and green all oversaturated. Color management tools would help pull these color points back in and more closely match the desired coordinates, as seen in Figure 6.

Figure 6. The plotted color gamut of the VF551XVT, compared to the BT.709 standard.

IMAGE QUALITY

This TV produces extremely sharp images that are rich in detail, no matter whether you are looking at a Blu-ray disc or an over-the-air broadcast. I selected scenes from Mission Impossible III to evaluate the judder-correction circuits and also to look at low-level image detail. For motion blur, I watched the Cowboys-Eagles Sunday Night Football game, carried over the air in the 1080i HD format from NBC stations WNBC-DT in New York and WCAU-DT in Philadelphia.

MI III is a great BD for crunch-testing deinterlacing circuits. Start with the Vatican reception scene in Chapter 8 and that famous shot of the camera zooming back as it pans down the closely-spaced stairs; a shot that drives deinterlacing circuits crazy. The VF551XVT handled it with ease.

Turning on the TV’s Smooth Motion processor will reduce the film judder to zero, producing more of a live video feel than film. Vizio’s blur reduction approach is more effective than any 120Hz correction circuits I’ve seen to date, but not as detailed as the few 240Hz processors I’ve checked out. Is this good? Bad? Depends on how much of a film purist you are.

The subsequent kidnapping of bad guy Philip Seymour Hoffman and the destruction of the Lamborghini looked spectacular. But the underground scenes lacked detail in dark areas, a direct consequence of those high black levels. Once again, moving ever-so-slightly in my seat resulted in the washed-out screen effect, which is as distracting to me as DLP color wheel breakup artifacts.

Figures 7a-b. These photos clearly show the off-axis brightness uniformity problem as seen from two different angles.

The football game fared much better (unless you are an Eagles fan), as the average picture level was above middle gray even in the darkest areas. I paid particular attention to close-ups of moving players as the sideline camera panned with them across a busy background. Not only is this an image blurring challenge, you’re also likely to see MPEG blocking artifacts (I did) which are just as much a challenge to filter out without softening the image.

The VF551XVT did a good job here in preserving image detail. Just a slight amount of blur was seen on the tightest shots and fastest zooms, some of which probably originated in the camera itself. So the 240Hz circuit works. It’s still not as crisp as a plasma display, but a big improvement over all of the 120Hz processors I’ve tested.

On the other hand, go lightly on the MPEG noise reduction as it does soften the image slightly. MPEG noise is difficult to eliminate completely – it’s embedded in the digital signal and the only way to minimize it is through expensive, powerful image processing, or through low-cost, high frequency filtering. That’s the approach you’ll find in this TV.

CONCLUSIONS

There’s no question about it – for $2,200, you get a lot of TV with plenty of inputs and calibration options. All Vizio TVs are ‘plug and play’ and you can turn it on and start watching with minimal adjustment. Five HDMI ports may be more than you’ll ever need, but where’s the Ethernet connection for Internet video viewing? (Better yet, where’s the wireless Ethernet hookup?)

While the VF551XVT is a nice job by Vizio in most respects, the off-axis image washout was a real turnoff. You’d never see this problem on a plasma TV, and it reminded me of watching rear-projection TVs – you had to sit right in the center to get the best image quality. Keep that in mind before you decide to buy one.

Power consumption: The VF551XVT operated for four hours in Standard mode with the backlight set to 50, displaying widescreen and HD broadcast content. Average power consumption during that time was 169.1 watts.

SPECIFICATIONS

VIZIO VF551VXT
55-inch LCD HDTV
MSRP: $2,199

Specifications:

Dimensions: 51.5″W x 35.9″H x 13.47″D with stand
Weight: 90.25 lbs w/stand
Resolution: 1920 (H) x 1080 (V)
Backlight: Direct Type LED Backlight Technology with Smart Dimming – 960 LEDs (80 control blocks)
Inputs: 2 composite, 1 S-video, 2x YPbPr component, 5x HDMI, 1x VGA, RF
Receives: ATSC, NTSC, unscrambled QAM
Compatibility: NTSC/PAL, VGA-XGA, 480p, 576p, 720p, 1080i, 1080p
Speakers: 15 Watts x2 (multi-speaker systems)

VIZIO
39 Tesla
Irvine, CA 92618
888.849.4623
www.vizio.com