Giant, 4K bears are terrifying.
The price of 4K televisions has reduced dramatically over the past couple years, but that drastic price drop has eluded the projector market until recently. Earlier this year, Optoma released its UHD50 4K projector, which was seriously affordable (for a 4K projector) at just $1,400, and now Viewsonic has followed with the similarly affordable PX747-4K (See it on Amazon). The affordable price is due to the fact that these projectors don’t natively output 4K, but instead use a technology dubbed XPR. But what is XPR, and should you care?
Viewsonic PX747-4K – Design and Features
The Viewsonic PX747-4K is a high brightness DLP (Digital Light Processing) projector with XPR technology, as mentioned above. Single-chip DLP displays like the PX747-4K work by projecting light through a color wheel, then off of a bunch of tiny mirrors (usually one for each pixel) and then through the lens and onto the screen. The PX747-4K has a RGBW color wheel that helps boost the white light output. The DLP chip in the 747 is a 1080p chip, so in order to get the resolution up to 3840×2160 it uses a pixel shifting technology that Texas Instruments (the makers of the chip) call XPR. DLP chips use mirrors to reflect the light and each pixel has its own mirror on the chip. The chip in the Viewsonic only has 1920×1080 worth of physical pixels mirrors and in order to get the full 4K resolution (or more accurately 3840×2160) each mirror projects four pixels. It’s done so quickly that our brains perceive it at four individual pixels happening at the same time.
The projector is rated at 3,500 ANSI lumens, which is very bright for a home projector this size. You shouldn’t have any issue having this in a room with ambient light, especially in its normal brightness setting. In that setting you’ll get around 4,000 hours of lamp life. The lamp’s life gets extended to 15,000 hours in Eco mode, but the light output has to be dialed down significantly. There is also a Dynamic mode, which I recommend using, that acts like an auto iris and adjusts the light output based on the image it’s projecting. In any of those modes the cooling fan noise is negligible and not distracting.
On the top of the projector are the control panel buttons (if you don’t want to use the included remote for whatever reason) and the focus and zoom adjustment rings. It’s important to note that, like most DLP projectors, the PX747-4K does not have lens shift so you’ll need to be extra vigilant about horizontally centering the lens to the screen. There’s an adjustable foot to elevate the picture to the proper height if the projector is on a table or stand, and a keystone adjustment, although use this very sparingly as it will affect picture quality. The back of the projector has two HDMI outputs, one is version 2.0 (for HDR content) and one version 1.4. There’s also a legacy VGA port, 3.5mm audio in and out, a mini-USB for firmware updates, a RS-232 control port, and a USB out.
The remote control is small and light with a bright blue backlight that illuminates every key. Button placement is good, there are an ample number of quick access buttons for changing inputs or adjusting menu options. The odd choice is the colors assigned to the On and Off buttons. On is red, while Off is green (it’s marked this way in the manual as well), which makes no sense. There were numerous times I pressed the wrong button based on its color before I added the on/off duties to my home automation.
Viewsonic PX747-4K – Testing and Gaming
For testing color I used a Photo Research PR-650 and to measure light output I used the Konica Minolta LS-100 luminance meter. The PX747-4K projected test images from the Digital Video Essentials Blu-ray and UHD/HDR-10 test pattern suite from Diversified Video Solutions on to my 100-inch Stewart GrayHawk 0.9-gain screen.
Before we get to the projector let’s talk about Rec.’s. A Recommendation (or Rec. for short) is a technical standard put out by the International Telecommunication Union that is used to standardize a format. Rec. 709 is the high-definition standard that was originally released in 1990. It details resolution, frame rate, and color space. Color space refers to the range of colors a display can reproduce. Nothing can fully reproduce the colors we see in everyday life, so these color recommendations give parameters in the form of coordinates on a graph for primary (red, green, blue), secondary (cyan, Magenta, yellow) and white color points. A Rec. 709 color space is smaller (or encompasses fewer colors) than a Rec. 2020 (the UHD format specifications). As with Rec. 709, Rec. 2020 covers more standards than just color space.
The Viewsonic is a Rec. 709 color space projector and not the Rec. 2020 and WCG that I am used to seeing attached to UHD displays, so colors will naturally be more limited. Of the Bright, Standard, and Movie picture modes I used the Movie picture mode because it looks most accurate, which was backed up by the color point measurements. All the color points are a bit off, but for the most part I could only visually notice it in the green and cyan where I didn’t see the depth of saturation I expected. The grayscale became bluer as it approached a full 100% all-white field. This bluish tinge could be seen in the whites in the space shuttle and clouds on the NASA footage material from the DVE disc, which has a selection of test images used to visually check color accuracy. There is the possibility of fine-tuning the color accuracy in the menu if you have the ability, or money, to calibrate the projector. It can be a time consuming process and you’ll need a meter like the PR-650, test patterns of all the color points, and some calibration software.
Where the projector does fall short is in its contrast.
Where the projector does fall short is in its contrast. Blacks are more of a dark gray. This is a drawback of DLP in general and not specific to this projector. With HDR material the contrast ratio looked better, but it still won’t rival that of a good TV with local dimming.
Using the Leo Bodnar lag tester, the Viewsonic measured an input lag of 47.1ms. For regular viewing this number is fine, but when it comes to gaming it’s a little behind. Other projectors will have a gaming mode that brings the lag number into the teens, but the PX747-4K doesn’t have that option. At 47.1ms a casual gamer won’t notice a significant delay, but if you’re playing a shooter where reflexes can be the difference between a dodge or a headshot you might feel some of that delay. (The Leo Bodnar only measures input lag in 1080p, so these numbers do not reflect the input lag of a 4K signal.)
When watching and playing in 4K there was no way to tell that it wasn’t a native 4K image. The resolution looked beautiful. There was great detail in the First Order Dreadnought in the opening battle of The Last Jedi. The backdrop of space was still more gray than black, but it didn’t bother me as much against the bright explosions and planet D’Qar in the background.
…seeing a huge bear come at you in 4K on a 100-inch screen is terrifying
I could feel the cold Lara Croft was experiencing while exploring Siberia and avoiding members of The Order of Trinity. The snow had that slightly blue tinge I also saw in the space shuttle, but seeing a huge bear come at you in 4K on a 100-inch screen is terrifying. I knew it was coming and it still managed to cause my heart to race, as well as throw my concentration and miss the dodge button. I didn’t feel like the extra lag from the projector affected my gameplay.
I played a bit as another favorite heroine of mine when I started up Horizon Zero Dawn, but this time I was in 1080p on my non-pro PS4. Even with the lesser resolution the projector looked great. I’m always impressed by the visuals and world building each time I come back to this game and the Viewsonic only reinforces that wonder. During day moments the less than stellar contrast of the PX747-4K didn’t bother me, although I could notice it when night fell.
Since I had the projector on my ceiling for a couple weeks I used it for all of my regular daily viewing and came across a few issues. While watching basketball summer league (my toddler loves it) through my DirecTV box with a 1080i signal output the back and forth stuttered a bit. I could notice this with anything that tracked quickly back and forth. It was only mildly distracting and only happened in 1080i material (which for me is limited to satellite). There were also two moments a few days apart when the projector flashed full screen through the primary colors before coming back to the show I was watching (once on DirecTV and once using Netflix). I couldn’t force this to replicate, but it was odd. The last one is the beep that happens when you turn the projector on or off. It catches me off guard and startles me every time, especially when the projector is done cycling down, and there’s no way to turn the beep off, apparently.
The Viewsonic PX747-4K has an MSRP of $1,300 but can usually be found on Amazon for $1,245. It has been as low as $1,000 during sale periods.