Last year we tested the Epson LS10.000, a '4K Enhanced' projector that offers better-than-full-hd image quality, but has a high price tag of more than 6597 pounds / 7200 euros in part because of its laser engine. Since then, Epson made their 4k enhancement technology available in three more affordable models as well, namely the EH-TW7300, EH-TW9300 and EH-TW9300W. With prices that range from 2107 pounds / 2300 euros to 3115 pounds / 3400 euros these are not exactly entry-level projectors either, but for home cinema enthusiasts these are potentially interesting devices especially considering they are HDR-capable. We tested the top model of the series, the EH-TW9300W, which is supplied with an HDMI-transmitter that allows for wireless operation.
Slowly but surely more and more 4K Ultra HD material is becoming available. YouTube has a plethora of 4K videos and Netflix has a continuously growing amount of films and series that are also available in 4K. Aside from that there is of course Ultra HD Blu-ray, on which dozens of titles are available in higher resolution and with HDR. Ultra HD is especially a clear improvement for projectors, because the image diagonal of a projection screen is often a lot bigger than that of a television. On this size the added image sharpness is often clearly visible. However, projectors with ultra hd image chips are very expensive, which is why the price difference compared with regular full hd models is so big.
In order to achieve a higher resolution with an affordable hd panel, Epson uses a smart trick. Every image is shown twice behind one another, while the image is shifted upward and to the side half a pixel the second time. Because this pixel shifting is lightning fast, our brain does not see it as two separate images, but as a single image with a higher resolution. Because the image has a lot more (detail)information with the second reproduction, a picture is created that can show more detail and looks considerably sharper when using a 4K-source compared with regular full hd image.
In practice it turns out this trick works really well. As we found out when reviewing the LS10000, very fine text in 4K resolution is still readable. With video the difference between the 4K-enhanced image and that of a true ultra hd screen is a lot smaller in practice, and in many cases not even visible. This is due to the fact that video images are often made lightly blurred in order to counteract moiré and aliasing. While the difference between a projector with pixel shifting and a native 4K model can be seen with a really sharp 4K source, the difference is often very small in practice.