What is the ViewSonic PX747-4K?
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
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.
Overall the design, connections and remote control of the ViewSonic PX747-4K is what we would expect to find at this price point.
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
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.
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.
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
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.
- 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
- 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)
ViewSonic PX747-4K DLP Projector Review
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.
Contrast/Dynamic Range/Black levels
2D Picture Quality
Picture Quality Out-of-the-Box
Picture Quality Calibrated
Ease Of Use
Value For Money
Our Review Ethos
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