ViewSonic PX747-4K DLP Projector Review

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by Phil Hinton Nov 10, 2018 at 7:44 AM

  • SRP: £1,199.99

    What is the ViewSonic PX747-4K?

    The ViewSonic is the latest 4K DLP projector aimed at the home entertainment market and retails at the time of this review (November 2018) at £1200. It features the latest Texas Instruments 0.47” DMD XPR (1920 x 1080) DLP chip, which flashes four times in quick succession. This creates an image which, to your eye, appears to have 8.3 million pixels, the same as native 3840 x 2160 4K devices. The marketing material claims this is true 4K, but this isn’t technically the case given the way the image is created. However, it is far more cost-effective than producing native chips and at normal seating distances image attributes such as black levels, shadow detail, colour and white balance are more obvious between side by sides tests with native 4K projectors, than resolution alone. At those distances, it is trickier to see just resolution differences.

    The ViewSonic PX747-4K is clearly designed, (like all the 4K DLP budget machines we have tested), to be used in normal living rooms with light coloured walls and ceiling surfaces and some ambient light. It is also made from tough plastic and portable so it can be transported to a friend’s house for some gaming, or watching big sporting events on the side of a house or a wall at parties. It is not designed for home cinema use where critical viewing and the image quality is key. It doesn’t pretend to be that kind of projector and if that is what you are looking for, you need to look elsewhere and at a much higher price point.

    So given its intended use and market, let’s see how it measures up.

    Design, Connections and Control

    ViewSonic PX747-4K Design, Connections and Control
    It shouldn’t come as a surprise to learn that the recent influx of budget level 4K DLP models are all based on the same underpinnings and chassis, with just software tweaks and manufacturer specific items added. It keeps the costs down and allows development and R&D to be spread out, so no one company has to bear the weight of these costs. As such, most models have a similar looking body layout and the menus, while having different colours and naming conventions from each other, are also the same basic design and interface.

    The ViewSonic PX747-4K is white in colour and features a traditional ‘office’ look to the chassis design. Looking from the front, the lens is offset to the right side with the zoom and focus controls above this in a recess on the top plate. To the front left, there is the exhaust port for hot air and between this and the lens is an IR receiver. Still looking from the front, on the top plate to the back left are menu controls and power buttons should you lose the remote control, along with a rear IR receiver. To the right side of the body are the air intakes that draw in fresh air to cool everything down and around the back are the connections.
    ViewSonic PX747-4K Design, Connections and Control
    The connections are fairly basic and include 3.5mm audio in/out jacks, a PC VGA input, two HDMI inputs with one HDMI 2.0 HDCP 2.2 compliant slot, a mini USB service port, RS232 control port, a USB power port and a 12v trigger for use with screens or blinds. The supplied remote control is a short and stubby affair, which is made from cheap-feeling plastic but is well laid out and intuitive to use. It fits neatly in the hand with easy thumb reach to the main controls and it is backlit.

    Overall the design, connections and remote control of the ViewSonic PX747-4K is what we would expect to find at this price point.

    Features

    As we covered within the introduction, the ViewSonic PX747-4K uses the latest TI chipset to produce an image, which fools the eye into seeing 8.3 million pixels on the screen. It does this by flashing parts of the image four times to create the illusion of resolution. It’s clever technology that ultimately saves money when compared to trying to produce a native 4K DLP chip. As such, the ViewSonic PX747-4K will accept 4K content from external sources such as your UHD Blu-ray player and a streaming device such as an Apple TV 4K box or similar. Of course, it will also accept 4K games from appropriate consoles. That also means that the Viewsonic will take HDR10 signals and it will tone map these to the projectors capabilities. Just don’t expect HDR images as you know them from flat-panel TVs. The colour wheel is an RGBW unit and there is no mention of colour space coverage or if it has any special coatings to help it reach Rec.709 coverage. There is certainly going to be no wide colour gamut coverage here at this price point and with this technology.

    The menu system is comprehensive and offers up calibration settings that even more expensive displays shy away from. So we have full white balance and Colour Management System (CMS) controls available and two user modes for saving image set up. There are controls for selecting the HDR input type and EOTF from low, middle and high, although it has little effect on overall dynamic range, it merely makes sure that the image is tone mapped (gamma tracked) to suit the capabilities of the projector.

    There are also some video processing features on the ViewSonic and these are found under the MoviePro section in the advanced menu and give the options to enhance skin tone, colour and resolution that are basic colour and sharpness tweaks. There is no frame interpolation mode on the PX747-4K.

    Moving away from traditional AVForums areas of interest the ViewSonic does boast a claimed 3500 lumens output from its 240W lamp that would make it quite the light cannon and points to its real intended use. What we have is a DLP projector that will work very well in a normal living room with light colour walls and ceilings and some ambient light. It doesn’t matter that the screen will probably be a white painted wall or sheet pulled tight or that light is bouncing all around the room and back on to the image, washing it out. The ViewSonic PX747-4K is designed and featured to feel right at home doing just this with big screen football, the Olympics or the Super Bowl while you and your friends enjoy a few laughs and drinks, either indoors or out.

    This is not a serious level home cinema projector and it also doesn’t have the quickest lag input either at 55ms, meaning it will suit the big screen fun side of things, but probably not a competitive gamer who wants lightning-quick reaction times. It will, however, take 4K images from your Sky Q box for premiership football or other sports, or Netflix films and 4K Blu-rays, just don’t expect deep blacks or HDR images.

    Out of the Box Measurements

    Given the use case for this projector and the fact we haven’t found any information regarding the colour wheel having special coatings to hit Rec.709 colour gamut coverage, we are not really expecting world-beating results here. There are a number of picture presets to choose from, including white balance selections and gamma. User 1 was our chosen mode, which we set up with the Normal white balance, rather than Warm, as it was too warm, along with a gamma of 2.4 for our dark surroundings. If using the projector in a normal living room, you would choose 2.2 due to the brighter surroundings. With this all done we used our Klein K10-A meter, Murideo Fresco Six-G generator and CalMAN Ultimate software to set about measuring the results.
    ViewSonic PX747-4K Out of the Box Measurements
    ViewSonic PX747-4K Out of the Box Measurements

    For a projector at this price point, we were not surprised with the mixed results in the greyscale tracking (top left). We can see that the tracking is not entirely flat, with a blue spike in the mid tones and some red push at the brightest end. Gamma clips black at the lowest part of the image and is then too bright against the standard in the brightest parts of the image. With actual viewing material we could see whites were a little too blue and the blacks were clipped, which also lines up with what the graph is telling us, as well as the high DeltaE errors.

    Moving to how the ViewSonic PX747-4K covers the HD standard for colour to Rec.709 (top right) we can see why there was no mention of colour wheel coatings on the RGBW unit. As such, you can see massive hue errors with green, and Cyan is also restricted in terms of saturation and hue. This is simply because the PX747-4K is not capable of reaching the full Rec.709 gamut and what you are seeing is the native capabilities of the ViewSonic in terms of colour coverage. This will also apply to HDR content, so again, no wide colour support here, it struggles to reach Rec.709 HD. There is also an oversaturation of red that does make skin tones look a little rosy with on-screen material. Overall, we have seen better with the likes of the BenQ TK800, but nothing from the latest RGBW ranges that do much better at colour accuracy. But then again, these models are not designed for critical home cinema movie viewing to the standards. With actual viewing content, the image produced was acceptable for casual movie viewing and colours, for the most part, just looked a little muted with some shifts noticeable with some skin tones.

    Calibrated Measurements

    The PX747-4K from ViewSonic has some calibration controls available which means we can get the greyscale tracking better, but we can’t add what is not there when it comes to the colour gamut, which is already restricted.
    ViewSonic PX747-4K Calibrated Measurements
    ViewSonic PX747-4K Calibrated Measurements

    Looking at the greyscale first (top left) we can see that even with controls that are quite coarse in use, we managed to massage the tracking and get the majority of DeltaE errors under 3, so there are no visible issues seen with actual content. There was a spike of green and a brightening of gamma at 90% white, but this had no effect with actual viewing material. At the price point and with the restrictions of the technology the results were good.

    Moving to the colour gamut at Rec.709 (top right) we noticed that correcting the white point also stabilised some of the colour issues. Obviously, the gamut is still restricted from green and down through cyan and there is nothing we can do to help that out and add back what the projector can’t produce. However, we could fix a couple of minor saturation issues in red and fix the hue of green in the lower reaches of the image, which helped yellow out as well. We also found that with slight adjustments there were no issues of image artefacts, as those seen with HDR content that existed before we made the adjustments here. With SDR content we saw no issues before or after applying these fixes in the CMS.

    HDR Results

    Let’s get one thing straight from the start – this is not an HDR projector. The technology is so hard to replicate with projection that there is just no way a DLP like the ViewSonic can produce any specular highlights, dynamic range or the wide colour gamut to reproduce the format correctly. Even the far more expensive home cinema models from the likes of JVC and Sony really struggle to produce images that can convey the dynamic of an HDR image; there is no hope for this budget DLP.
    ViewSonic PX747-4K HDR Results
    ViewSonic PX747-4K HDR Results

    We had a look at the results produced anyway and for the EOTF tracking (top left) the ViewSonic basically rolls off at around 60 nits onwards to a manageable peak of around 200 nits. This keeps much of the detail in the highlights; mainly because it is not capable of producing strong enough brightness to clip them. Blacks are poor, as is shadow detail performance, which means there is no dynamic range to speak about. It is basically a slightly brighter native image with no HDR.

    Again, the ViewSonic couldn’t fully reproduce the colour gamut for Rec.709 HD material, so we had little expectation that it would do anything with HDR content and we were correct. We can see the restricted gamut capabilities with massive errors because of this. Again, this is not a WGC capable display and we didn’t expect it to perform very well here.

    ViewSonic PX747-4K Picture Performance

    Like I have done with similar 4K DLP projector reviews, it is important to set the expectation levels a little when it comes to picture performance. At this price point and with the technology available, we are not talking high-end home cinema quality images, so if that is what you are looking for you need to look elsewhere and at a higher price point. What we have with the ViewSonic is a home entertainment projector, which is aimed at causal movie viewing, gaming and big screen sports. The PX747-4K is portable and usable in a wide range of setups, from pointing at a white painted wall, to use at a BBQ pointing at the side of a house, to some users installing an electric screen and ceiling mounting. It is designed to be used in normal living rooms with light coloured surfaces and some ambient light present, given it brightness levels. So with that out of the way how does it perform?

    Let’s get the weaker points out of the way first of all. Black levels are a light grey at the best and there is no just above black shadow detail. Indeed there is no shadow detail at all, just a block of light grey in some tricky scenes with mixed content. Contrast is also quite poor and whilst the PX747-4K can go quite bright, the raised black level means there is no immediate pop or dynamic range to dark scenes. We measured an on/off contrast of 589:1, which is quite low even by DLP standards, in the best picture settings and full lamp mode. You can get closer to 1100:1 in the brightest and most inaccurate picture modes, but we’ll stick with trying for accuracy.

    Get away from dark scenes and switch to Planet Earth II with its tropical beaches and wildlife and the ViewSonic will get your attention with some nice colourful images. With this kind of material in normal viewing environments, the PX747-4K is really rather watchable with good skin tones on offer, even if the cheeks are perhaps just a little rosy in out of the box settings. Sharpness is also superb with pin sharp edges and no signs of ringing or artefacts to spoil things. Scaling a de-interlacing performance was also very good and motion was also spot on for 24fps material, with only source captured image blur on show. Sports viewing was also very good with no signs of judder or artefacts to spoil the action and, again, brightness and colours looked strong. The only times we really noticed the weakness of the ViewSonic was with low light and darker scenes where the image is washed out due to a lack of deep blacks and contrast. With all other material, the performance is what we would expect from a projector at this price point.

    While the ViewSonic can accept and show 4K UHD material with HDR, it doesn’t produce a very convincing HDR experience as it just cannot produce the contrast required or the wide colour gamut. Another issue is the 8-bit processing where gradational issues and image posterisation are also present with tough scenes. Blade Runner 2049 New Vegas is a torture test for even the best HDR TVs and here the ViewSonic PX747-4K really struggles with obvious gradations and posterisation around the mist covered sun in the sky and with the changes in the orangey yellow mist. Blacks are a challenge for this projector and as such you really do miss out on the finer touches in the lower ends of the image. Black crush is very apparent as well. But of course, that is under critical viewing conditions.

    Judged at its intended use the ViewSonic offers cheap big screen fun with an image that holds up with normal TV and some casual film viewing. Gaming is also very good and although input lag is not the fastest, most gamers will not notice any real issues that will affect their performance here. Colours remain vivid and forceful, which I guess is what you are looking for from this type of product.

    Conclusion

    7
    AVForumsSCORE
    OUT OF
    10

    The Good

    • Good brightness for use in normal living rooms
    • Good motion for sports viewing
    • 24fps motion is good without excessive judder or image blur
    • Image sharpness is good
    • Can accept 4K UHD HDR sources
    • Portable and easy to set up

    The Bad

    • Mediocre black levels and no shadow details
    • Crushes blacks
    • Not a home cinema projector
    • Not an HDR projector
    • RGBW colour wheel restricts Rec.709 gamut coverage
    • Some rainbow effect visible with fast moving content
    • Noisy in use, even in low lamp mode (29db)
    You own this Total 1
    You want this Total 0
    You had this Total 0

    ViewSonic PX747-4K DLP Projector Review

    The problem the ViewSonic has is the competition from very similar products from the likes of BenQ at similar price points. They all have very similar end goals and produce similar images. None of them has particularly good black levels or shadow detail and contrast performance is also poor. One or two have better accuracy with SDR colour gamut and white points, but again, that’s not really the intended audience for products like these projectors.

    As such, we have to score the PX747-4K based on its intended use and audience. The weak blacks and poor contrast are not such a major issue in a light coloured room with light bouncing off all the surfaces and whatever is being used as a screen. In such an environment you need brightness and vivid colours more than inky blacks that would get washed out anyway. So the lack of contrast and black levels are not an issue, so it comes down to other image attributes. As such, the ViewSonic has a decent colour performance and lovely sharp detailed images that are free from any artefacts with SDR material. Scaling and video processing performance are also strong and the projector deals with a number of sources well. It can show you 4K HDR content, just don’t expect the HDR part to be up to much, because it isn’t, and for sports, motion is also very good. You could use this in a home cinema but just be aware of the issues we have highlighted and get a good quality demo.

    Used as a home entertainment product the ViewSonic fulfils its potential for that audience and as such, it scores roughly the same as its peers we have already tested. It then just comes down to price and any other features you might want, and that’s going to be your decision to make.


    Suggested retail price when reviewed: £1,199.99

    The Rundown

    Contrast/Dynamic Range/Black levels

    5

    Colour Accuracy

    6

    Greyscale Accuracy

    6

    Video Processing

    7

    Image Uniformity

    7

    2D Picture Quality

    7

    Picture Quality Out-of-the-Box

    6

    Picture Quality Calibrated

    7

    Features

    6

    Ease Of Use

    7

    Build Quality

    7

    Value For Money

    7

    Verdict

    7

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