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First Look at the Philips 901F Ultra HD 4K OLED TV

Philips combine OLED with their picture processing expertise to great effect

by Steve Withers Sep 2, 2016


  • Philips have finally embraced OLED and their picture guru Danny Tack was on hand to explain the processing in their new 55-inch 901F and the benefits of the technology.
    After rather letting the cat out of the bag back in February with his unplanned announcement that Philips would be launching an OLED TV at IFA, it was time for Danny to finally put us out of our misery and see exactly what he has been working on. Danny started by admitting that whilst he had criticised OLED in the past due to its lack of overall brightness, he now felt that the benefits of OLED outweighed any limitations in its brightness.

    He also felt that OLED had now reached a point where its brightness was comparable with most LED/LCD HDR TVs that can only hit up to 700 nits of uncalibrated peak brightness. However he did admit that the full screen brightness of an OLED TV is far less than an LED/LCD TV, around 150 nits as opposed to 500 nits, but that could be mitigated though effective picture processing. However before he started discussing the picture processing Danny quickly went through the strengths of OLED as an image technology.

    Philips 901F

    Anyone who has read our articles and reviews of OLED TVs over the last couple of years will know that the technology has certain areas where it is clearly superior to LED/LCD. The first is in terms of its contrast performance, with the OLED panel delivering deeper blacks, essentially down to 0 nits and more precise and thus brighter highlights. This gives an OLED panel a huge contrast ratio when compared to even the best VA LCD panels. Although an LED/LCD TV can have over 500 independent dimming zones that still isn't enough to eliminate the problem of haloing, whilst an OLED, being self-illuminating has effectively over 8 million individual zones.

    An OLED TV also has near-perfect viewing angles, resulting in much wider optimal angles that retain contrast and colour saturation. This is an area where VA LCD panels particularly struggle. An OLED can also deliver a very Wide Colour Gamut (WCG) and the 901F can reproduce up to 99% of DCI-P3. However an OLED TV can also deliver these wider colours consistently over the entire luminance (brightness) range. That means that colours look more saturated on an OLED than on an LED/LCD, even in darker scenes.

    When it comes to motion OLED has a much shorter switching time compared to liquid crystal based technologies, delivering around 0.01ms instead of 5ms. This results in sharper motion behaviour, although it isn't perfect because there is still the issue of 'sample and hold' and Danny reckons this accounts for 30% of the issues related to motion handling, even on an OLED TV. The 901F has a 200Hz frame rate coupled with Philips's usual array of motion enhancement features which, whilst they shouldn't be used for film-based content, can be be very useful with sport.

    Philips 901F

    Danny feels that the Philips OLED TV stands out in picture quality thanks to their Perfect Pixel Ultra HD Engine which focuses on four elements that the eye can actually see. First of all there is the Ultra Resolution feature that not only upscales lower resolution content to precisely match the screen's native resolution but also improves the perceived quality of an Ultra HD source. There is also a superior colour performance thanks to the combination of a wide colour gamut and 17-bit colour processing (although the panel itself is 10-bit), resulting in 2.25 trillion shades of colours.

    In Philips's LED/LCD TVs they have local dimming and the best version is called Micro Dimming Premium but since an OLED can effectively dim at a pixel level rather than in a couple of hundred zones, it's capabilities are called Micro Dimming Perfect. Other key processing features include spatial-temporal DNR and MPEG noise reduction, smart bit enhancement for smoother image reproduction, mosquito noise reduction and additional local contrast improvements on top of the OLED panel's existing superiority in this area. The 901F is certified as Ultra HD Premium by the UHD Alliance, which means that it can deliver a peak brightness of at least 540 nits when accurately reproducing D65. Danny said the TV could deliver a peak brightness of up to 700 nits if you didn't care what white looked like but we prefer our whites to be accurate.

    Danny demonstrated the superior performance of the 901F compared to Philips's LED/LCD TVs and the blacks were indeed as impressive as we would expect, as were the colours. Danny does have an annoying habit of conducting all his demonstrations in Vivid mode but the potential of the 901F was clear to see. The motion handling examples looked particularly good and with HDR content, the OLED TV was able to deliver plenty of detail when compared to the same footage in SDR. However the LED/LCD TV was clearly brighter overall with HDR but despite that limitation the 901F delivered a fantastic picture compared to an LED/LCD TV.
    The combination of an OLED panel, Philips picture processing and Ambilight makes the 901F unique
    Philips 901F

    However whilst the new 901F already combines a state-of-the-art OLED panel with Perfect Pixel Ultra HD image processing, what makes it unique is the inclusion of Philips's Ambilight. This proprietary technology uses LEDs built into the rear panel to illuminate the wall behind the TV. There are some people who swear by Ambilight but we've never liked the disco lighting effect of different colours behind the TV. However the D65 mode creates an excellent neutral bias light behind the TV that can make for a more comfortable viewing experience at night.

    The 901F supports HDR10, so Danny described the benefits of the new format and its ability to deliver deeper blacks and brighter highlights whilst still retain detail in shadows and the brighter parts of the image. He had some interesting things to say about exactly how HDR10 is implemented because its open-source nature gives manufactures a lot of leeway. Under the UHD Alliance guidelines for Ultra HD Premium certification an HDR TV must be able to tone map out to 4,000 nits without clipping. The 901F has a Perfect Contrast setting in the menu and if you leave this off, then the TV is tone mapping out to 4,000 nits without clipping. However there are three other settings of varying degrees of effect that clip at 1,000 nits but were able to deliver a brighter overall image. Danny demonstrated this feature and whilst the overall image was brighter using the different settings in Perfect Contrast, the clipping was obvious in places and we would prefer to turn the feature off and tone map correctly.

    Danny said that whilst there was still a limited amount of native HDR content, he could see a reason for including a faux HDR image that he calls HDR Upscaling. In much the same way 4K upscaling allowed people to enjoy their new 4K TV before there was any Ultra HD content, so Danny feels that HDR Upscaling will allow people to get a HDR-like experience from SDR content. He demonstrated this feature using three 901Fs – the first showing SDR content, the second showing the same SDR content but with HDR Upscaling and the third showing the same content graded in HDR. Naturally the the HDR footage looked vastly superior but the HDR Upscaled footage often looked quite good, although the bright parts of the image were completely clipped. As always we would rather watch SDR content on a display correctly setup for SDR and HDR content on a display that is correctly setup for HDR but we can see the upscaling feature being popular with consumers.

    Philips 901F

    It shouldn't come as a surprise to discover that the 55-inch OLED panel was sourced from LG Display, who else are Philips going to buy them from, but it's strange that they didn't also offer a 65-inch version because LG make that screen size as well. Philips didn't actually explain their reasoning but it's possible it was either a cost or a supply issue or possibly they felt that 55 inches offered a sweet spot in the OLED TV market. We asked if Philips were taking any special precautions against image retention or screen burn but Danny said that those features were already built into the panel by LG Display and they aren't doing any more than LG do with their OLED TVs.

    It was also no surprise when Philips confirmed the 901F doesn't support 3D, after all the manufacturer have dropped that feature from all their TVs this year. However it was more surprising to discover that the 901F doesn't support Dolby Vision, especially as LG do so on their 2016 OLED TVs. When asked about this Danny said that he just felt there simply wasn't enough Dolby Vision content to warrant including it on the 901F. At present only Netflix offer Dolby Vision on certain HDR content in the UK but all the HDR content on Netflix, Amazon and Ultra HD Blu-ray is available in open source HDR10. Whilst there is also a question of licence fees Danny said that he had yet to be convinced that Dolby Vision really offered any benefits on a high-end HDR TV.

    We asked him about the benefits of dynamic metadata and he said that it seemed more relevant with streamed content or HDR TVs that use edge-lighting or have a lower peak brightness. He also pointed out that in the near future HDR10 would have dynamic metadata as well, although it would require HDMI 2.1 to be delivered; something that might not be the case with Dolby Vision. When we asked him about Hybrid-Log Gamma (HLG), he said that was a completely different matter and he expected that to become the primary method of delivery for broadcast HDR and that there would probably be an HLG firmware update for the 901F at some point.
    The 901F supports HDR10 rather than Dolby Vision but there will probably be an HLG firmware update at some point
    Philips 901F

    The TV itself is very attractive up close, with a 1cm wide black border around the screen, a chrome trim around the outer edge, and matching chrome feet. The feet are at the edges of the panel and stick out slightly, so you'll need a fairly wide surface on which to install the 901F. The rear has a nice brushed metal finish, with removable panels that cover the connections. There is an illuminated logo at the bottom of the screen, although this can be turned off, and beneath that is the soundbar with six forward-firing drivers and downward-firing woofers. There is also a Dolby logo on the soundbar which relates to the TV's ability to decode Dolby Digital but we pointed out that it might result in people confusing it with Dolby Vision.

    In case you're wondering, the 'F' in 901F stands for flat. This is because there is also an curved 901C but this is exclusively for China. The 901F will be available in the UK in early November and will retail for around £3,499. In our first look at the new Philips 901F, we found it to be an attractively designed and impressively performing Ultra HD 4K OLED TV but at the same price as LG's 55E6 it might struggle to compete when the latter includes both passive 3D and Dolby Vision. However it is always good to have another manufacturer in the OLED market and nice to have the option of choosing a 55-inch model from someone other than LG.

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