True 4K vs Faux-K
Epson Home Cinema 4000
This is a different comparison entirely. The ViewSonic PX727-4K has the 0.47" DLP chip with a 1920 x 1080 mirror matrix, generating a 4K picture (8.3 million pixels) via four-phase pixel shift. Meanwhile, the Epson HC 4000 uses 3LCD chips with the same 1920 x 1080 pixel matrix, but it has only a two-phase pixel shift. So it does not produce 8.3 million pixels, and Epson has never represented that it did -- they market this class of projectors as 4K-enhanced. So the HC 4000 paints two slightly offset 1920 x 1080 images per frame while the PX727-4K paints four. In theory the PX727-4K should produce a sharper picture in terms of image detail, and it does.
So, what differences do we see? When viewing the Epson HC 4000 from our close-up distance of 12 inches from a 5-foot wide screen, there is no distinct pixel definition. The two-phase shift in this implementation tends to blur any hint of a discrete pixel matrix. In this regard it is extremely similar to the PX727-4K. When viewed very close up they look not quite perfectly identical as far as the indistinct pixel array is concerned, but they are pretty darned similar.
Now, let's back up to a more practical viewing distance. This time we will stand 5 feet from our 5-foot wide screen (1.0x the screen width). Can we see any difference in image sharpness and detail? Yes, the PX727-4K is the sharper of the two. And this is true no matter if you are displaying a native 4K video signal, or if you are displaying regular HD 1080p and having the projectors upscale it. It is not surprising that the PX727-4K can deliver more 4K detail from a 4K signal, but it is surprising (to me anyway) that it can even upscale HD 1080p with a higher apparent level of precision. This four-phase pixel shift is remarkably potent as far as rendering detail is concerned.
HOWEVER. And this is a huge however - the Epson HC 4000 is much higher in contrast with much more solid black levels than the PX727-4K. And as we know, high contrast makes a picture look sharper. So when we back up from the screen to a viewing distance of 1.5x the screen width and put on some 4K HDR material, the Epson 4000 actually appears to be a bit sharper than the PX727-4K.
This is due to a combination of factors - as you move back from the screen the advantage the PX727-4K has in rendering fine detail becomes less visible so contrast becomes a more dominant factor in your overall perception of the picture's sharpness. So as your move back your perception flips and the Epson 4000 looks like the sharper of the two projectors.
The point at which this occurs depends on the contrast of the subject matter, but with the 4K HDR movie Lucy it appears to happen at a viewing distance of about 1.3x the screen width (with my 20/20 vision). In point of fact, the effect is somewhat of a hybrid, with some elements in the picture looking sharper on the PX727-4K, and other elements looking sharper (or at least as sharp and more three-dimensional) on the Epson 4000. In this no-man's land, where the latent competitive strengths of both projectors are visible simultaneously in the same picture.
In the end, this comparison illustrates that contrast is a huge mitigating factor that can outweigh the perception of image detail, sharpness, and clarity. Small differences in image detail which are obvious when examined close up become insignificant or even invisible when you sit back to enjoy a movie in a typical theater set up. Meanwhile, contrast is of utmost importance.
|Contents:||Intro||Optoma UHD60 vs UHD50||ViewSonic PX727 vs Epson 4000||Optoma UHZ65 vs Sony VW285ES|
|What Makes a 4K Projector|