What is 4K Pro-UHD?

Epson claims that its halfway-house 3LCD version of UHD 4K definition can provide better results than 4K DLP projectors, thanks to other key attributes.

Three new projectors have arrived from Epson, all “crafted to a level” as it was nicely put to us at the Sydney launch, that level being a sub-$5000 price for what the company calls ‘4K PRO-UHD’ projection. But what exactly is 4K PRO-UHD? Well for starters, the 4K in 4K PRO-UHD is not native 4K. The three new Epson projectors use a 1920 × 1080 panel, pixel-shifted once to deliver around four million pixels, half the number of actual UHD, and overlapping too (we’ve never quite been able to get our heads around the geometry of this pixelshifting method of resolution raising). Epson describes it as 4Ke, or ‘4K enhanced’.

But hold on before you head off in search of the real thing. Epson has some good arguments for why their choices may deliver a better end result on your screen than other systems which create full UHD resolution from multiple passes of a 1080 panel, even potentially better results than from native 4K chips. Because resolution isn’t everything.

Top of Epson’s list in this regard is brightness, which has always been in the company’s favour, because Epson’s 3LCD panels continuously and simultaneously project separate Red, Green and Blue colours, whereas the DLP chips from Texas Instruments have to split their

available brightness in the time domain through multiple turns of a colour wheel, and in the case of the multi-flash DLP470TP DMDs (Digital Micromirror Devices) also into four flashes for different pixel positions.

In specifications terms, Epson’s higher continuous brightness is most obviously indicated by the lumen levels, with many 4K DLP projectors delivering somewhere in the 1500-2000 lumen area, while for individual colours they wouldn’t get even close to that.

The new Epson models each deliver 2600 lumens, and Epson is able to quote both a white light output figure and a colour light output figure of that same level, to emphasise the difference their technology brings.

Contrast is also a crucial factor in terms of perceived image quality, and the Epson models quote 1.2 million to one for the two higher models and one million to one for the lower model. Both figures are far above the numbers given for DLP projectors, even those with a dynamic iris.

It’s also easy to understand the benefits at the pixel level, because Epson uses 0.74inch panels, compared with DLP’s 0.47-inch panel for those projectors using the XPR ‘four-flash’ DLP470TP micromirrors. That’s a big difference in the area available, so that each pixel is larger, brighter and, all other things being

equal, also less prone to noise. The same debate is active in the camera industry, where the argument of ‘more pixels’ versus ‘larger pixels’ invariably comes down on the side of larger pixels.

High Dynamic Range

In practical terms a brighter image means a projected image that is better able to survive a little ambient light in the room. And it also speaks to the ability to deliver the best from High Dynamic Range content — certainly to produce whiter whites without crushing at that end of the scale.

At the launch in Sydney, Epson showed us interesting and informative graphs of how their projectors can achieve a more accurate and higher-nit transfer function of the ideal HDR curve onto the screen from their projectors than can rivals. But they subsequently asked us not to show you those graphs, saying “we are not able to share this information with public”, so it’s hard to give those credence.

Epson also promoted the colour benefits (100% DCI-P3 space) and even the detail benefits (the latter perhaps a surprise given it’s not true 4K), and also the quality of the glass in its 15-element aspheric glass structure.

Positioning versatility of the three new projectors is also exceptional, with three-axis motorised adjustment, 96% lens shift vertically and 47% horizontally, with 10 available position memories, handy for different source scenarios, anamorphic use, or should you like to shift your Epson around. See our review of the $4999 EH-TW9400W (p50) for more; the other two models are the EH-TW9400 at $4799 (a $200 saving for the same projector without the wireless HDMI connection), and the EH-TW8400 at $4099, which also shares most of the specs of the others but offers that mere 1 million contrast ratio. See our review starting on p50 for more.

Website: www.epson.com.au