Shootout: Sanyo PLV-Z4 vs. Optoma H79

Evan Powell, November 2, 2005

Over the past couple of years the native 1280x720 resolution LCD projectors have competed against their DLP counterparts by undercutting them in price. By doing so, they have delivered remarkably good value—excellent video quality for the money. Meanwhile, DLP projectors have been able to command premium prices largely due to their superior performance in contrast and black level. Thus, the primary trade-off between LCD and DLP, given the same resolution, has always been contrast vs. price. Every year both DLP and LCD projectors deliver higher contrast than they did the year before. Consequently, DLP has been able to maintain the perception that it is the "best" technology for great video.

The latest high contrast LCD projectors represent the industry's first serious threat to this established paradigm. They have set radically new performance benchmarks at prices in the low £1,000s. Accordingly they challenge the viability of the large price gap that has existed between 720p LCD and 720p DLP projectors. To illustrate the phenomenon, we set up the new Sanyo Z4 LCD projector against a premium DLP product, in this case one of our all time favorites, the Optoma H79, which came onto the market about nine months ago.

The Optoma H79 has been widely recognized as being an outstanding value for the money. At this writing it has an MSRP of about £6,000, and a street price of about £3,500. It features the latest 1280x720 resolution DarkChip3. In our view it was and still is a beautiful projector. By comparison, the LCD-based 1280x720 resolution Sanyo PLV-Z4 has a retail price of just £1,400. So they are in two completely different price classes. The question is, ignoring the prices and the specs, how do they look side by side?

The Shootout

At the outset, it is most important to underscore the fact that these projectors perform differently based upon the type of video source they are being fed. One can make either projector look better than the other simply by choosing video material that one is particularly adept at. So one must be skeptical of side by side demonstrations staged by folks who may be promoting one model over the other. The bottom line is that each of them has an advantage over the other with certain types of material.

Let's start with a basic weakness of the PLV-Z4 and put it into perspective. As noted previously in the Z4 review, the deinterlacing capability in this projector is surprisingly remedial. That means that standard definition interlaced sources such as 480i component from a DVD player or TV cable box, or S-video from a VHS tape deck, laserdisc player, and so on, are displayed with quite a bit of deinterlacing instability, to the point where it is unacceptable.

There are two ways to get around this problem. The first is to use progressive scan DVD players and cable/satellite boxes. If you don't have VHS or laserdisc sources to worry about, this is the easy and inexpensive solution--you can easily incorporate progressive scan sources into your home theatre that bypass the Z4's internal deinterlacer, and thereby eliminate the problem. On the other hand, if you happen to have a treasured collection of laserdiscs that you want to see at their best, and your laserdisc player does not convert to 480p, an external video processor is the best way to go. You can add something like the DVDO iScan processor to your system for about £700, and that will convert all of your interlaced sources to progressive. You must shell out some extra cash, but keep in mind that after factoring in the incremental expense of the processor, you have a comprehensive video system solution that is under £2100, or much less than the price of the H79.

Assuming you plan to resolve the 480i deinterlacing issue one way or the other, the Z4 can then be placed side by side with the H79 with some very interesting results. The first thing that becomes evident is that the Z4 delivers a sharper image than the H79. Now the H79 has a clean enough image, to be sure, and standing alone it looks fine. But the Z4 is so razor sharp that it makes the H79 look soft. And the difference in image acuity between these two projectors is the same regardless of whether the source is standard DVD or HDTV 720p or 1080i, and whether it is video or data graphics. We have seen projectors that rival the image sharpness of the Z4, but they are usually in the £5,000 and up price range. We have not yet seen anything in the low £1,000's that can match it. And by the way, this is true even with the sharpness control turned almost all the way to the Off position. The Z4's sharpness scale runs from a minimum position of -7 to a maximum enhancement position of +7; we set it at -5 for all of our comparative testing.

Another advantage of the Z4 is that it has a more stable image. It is less susceptible to noise throughout the gray scale. This is not to suggest that the Z4 is noise-free; certainly it is not. However, wherever there was a hint of noise on the Z4 there was almost always more noise on the H79. Where there was dithering in the shadow areas on the H79, there was a stable image on the Z4. This translates to a smoother image on the Z4. In facial close-ups, skin texture appears even and smooth, whereas in comparison there is a subtle graininess on the H79. Similarly, in solid highlights such as a white vehicle in direct sunlight, the Z4 displayed a pure smooth paint finish, while there was some sparkling on the H79.

Traditionally, deep black levels have been an impressive attribute of DLP projectors. The H79 is certainly no exception. In this side by side test, the H79 was able to deliver blacker blacks than the Z4. Furthermore, in dark scenes the H79 was better at separating shadow details. The Z4 was remarkably competitive considering that it is LCD, but DLP's incremental advantage in black level and shadow separation persisted in this particular comparison. However, the H79's advantage is limited to scenes with low average light levels. In bright or moderately lit scenes the H79 showed no advantage in contrast over the Z4.

In terms of colour performance, both of these projectors are exemplary. With some further tweaking, we were able to eliminate the slight orange bias in the reds that we had reported earier in the Z4 review. In fact, we were able to get these two units calibrated to the point that their images appeared virtually identical in many respects. We watched an interview being broadcast in HD 1080i on HDNet in which colour balance, colour saturation, contrast, and shadow detail was for all practical purposes identical. Viewed from a distance, it was hard to believe that one image was coming from LCD and the other DLP—indeed, it was hard to imagine they were two different projectors. This is ultimately where advances in technology must lead. For both technologies are converging on the same ultimate goal, which is to reproduce a pure, natural image as it appeared in front of the camera to begin with. It is only a matter of time before it will be impossible to tell from the image itself whether there is LCD or DLP technology inside the projector. From the results of this test, it appears we are closer to that goal than we had imagined.

As far as pixelation is concerned, the Z4 has a more distinct pixel structure when examined close up. The H79's pixels are distinct as well, but with a less visible interpixel gap. This is typical of LCD and DLP technologies respectively. LCD has made great strides in reducing the interpixel gap, and thus reducing the visible pixel grid, or "screendoor effect," that used to be a pronounced attribute of LCD projectors.

From most normal viewing distances the pixel grid on the Z4 is not visible in video. As with any projector, it becomes visible first in white highlights, such as lettering in subtitles and rolling credits. That is because the colour white produces the maximum contrast with the gray shade of the interpixel gap. If you wish to sit back far enough to eliminate the visibility of the pixel structure in the white highlights, then one must view the Z4's image from a distance of about 1.5 times the screen width. One may sit as close as 1.0 times the screen width with the H79 before pixel structure becomes visible. However, we would not recommend sitting any closer than about 1.5 times the screen width with the H79 either, since the digital noise and dithering becomes more distracting the closer you are to the screen.

Therefore, we may summarize the characteristics of each projector as follows: First, the Sanyo PLV-Z4 delivers a razor sharp, smooth, stable image that is comparatively low in noise. Colour is rich and beautifully saturated. Black level is solid enough to produce an entirely satisfying image, but deep blacks, as in a starry black sky, are not as black as they are on the H79. Overall, the most noticeable shortcoming on the Z4 in comparison to the H79 is in the separation of shadow details in dark scenes.

The Optoma H79 produces excellent contrast and dynamic range, with very deep black levels, brilliant whites, and good detail separation in dark scenes. Colour performance rivals that of the Z4, with the Z4 maintaining a subtle edge. The H79's most notable shortcomings relative to the Z4 are a comparative softness in the image, and more noise and dithering that tend to impart a slightly grainy texture to the image.

So--which projector would we buy? They are both great projectors, and both have their faults and limitations. Each will appeal to a certain type of user. Nevertheless, we can say this: the Sanyo PLV-Z4 really shines with bright films, animated films, and most HDTV. It outperforms the H79 with highly saturated, high contrast material like Shrek and Austin Powers, by rendering a sharper image with less digital graininess. The overall result is an image with a smooth, filmlike quality.

On the other hand, films with a lot of dark content such as Heat and The Bourne Identity tend to show better on the H79 due to its ability to bring out more shadow detail and produce an incrementally blacker black. The downside is that improved shadow information also contains more dithering and noise. So neither projector does an ideal job with dark scene material, but their shortcomings are different. Some viewers will prefer the H79's better shadow detail along with the noise, and others will prefer less shadow detail in favor of the Z4's sharper, more stable image. We get into personal preferences here, and there is no solution that is objectively "better."

This shootout indicates that we have reached a fundamental turning point in the industry. For the first time in our experience, an inexpensive LCD projector can be placed along side a well-regarded high performance DarkChip3 DLP projector, evaluated purely for its image quality, and not come off second best. With some types of video material the Z4 will actually surpass the H79 in overall image quality.