You had to brave the heat and crowds at Roland Garros on Thursday afternoon to go to a demonstration HDR (High Dynamic Range), orchestrated by Sony. The opportunity to see the practical application of HDR benefits in post production. A treatment that could ultimately benefit all televisions and not only to those who offer them via the HDR backlight. Explanations.
HDR will be a folder in our columns as soon as possible. Meanwhile, quickly remind that this technology is here to offer video on a bigger light range than current videos (which are in fact in SDR, or Standard Dynamix Range). In practice this allows to see much more detail in dark scenes and bright scenes. We can also draw a parallel with the HDR photos, even if the capture is not the same, since we must take at least two shots at different exposures with a camera (commonly, one for capture details in the dark and one for light) before making an average, so as to avoid clogged blacks and whites burned.
A TV Sony KD-75X9405C equipped with HDR firmware. If the TV is due out this month, the HDR firmware is projected to happen to him later in the year.
HDR video is seen first on the new high-TVs range unveiled at CES 2015 (for example, Samsung UE65JS9500). These TV indeed introduce a localized backlight, able to go up to 700 or 1000 cd / m². They can represent so much more faithful light sources, to offer a more mixed picture. But we must admit that with one or two models from each manufacturer maximum and a price to thrill the public, this technology, enjoyable and innovative as it is, is still very accessible.
Concrete example, the sun, mastering HDR allows show the details of the hair, while on the SDR, whites are burned.
However, the other interest HDR comes from the mastering , the phase during which the image is reworked after capturing with his camera. And precisely this step enables us to offer the benefits of HDR to all, regardless of the TV. It is precisely to illustrate this phase that Sony invited us to discuss it with Patrick Profit, documentary filmmaker, but cameraman. Taking advantage of the Roland Garros tournament, it captured some footage to compare the rendered HDR and SDR side by side, on OLED screens monitoring calibrated identically. The videos were captured in 16-bit (or 4: 4: 4 image for connoisseurs) and is in post production as the work of adaptation to current distribution media is. The final image must indeed be broadcast on 10 bits (4: 2: 2), while keeping a myriad of details at all levels. Rendering is the much more detailed stroke, especially in the scenes of chiaroscuro. No more white burnt in a very bright image and black totally plugged in dark areas. The Ultra HD also takes its meaning in these conditions, thanks to its remarkable dive.
More details in the dark while keeping brighter areas clearly visible.
Still, in absolute terms, our current TVs in consideration of the image more detailed risk losing dynamic is not negligible. Of course, we will benefit from additional details, but abuse the risk of giving HDR images that are starved of amplitude, with too much compromise on brightness and finally made too balanced. If the rendering is certainly more in line with what the human eye can perceive in reality and is well suited to documentaries and sports broadcasts, its application to improperly cinema could scream the fans, with a loss of bias film. What about, for example, a Nostromo in Alien that would reveal all its passageways in the background instead of leaving them immersed in an oppressive dark? If undoubtedly the mastering HDR provides benefits, it therefore leaves also some outstanding issues that we wait to see resolved. But for this we will have to wait because the HDR contained in our homes, it’s not for now.
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