Definition November 2021 - Web


Speed and power One of the most powerful aspects of LED panels is their sheer brightness, enough to cater to HDR shoots in certain configurations. Roe Visual’s panels include the CB5, capable of 6000 nits, which is half a stop more than any HDR display ever developed for grading. The Black Pearl series includes the BP2V2 panel, specifically designed for film and television work; its 1500-nit brightness exceeds a lot of HDR reference monitors. Brompton Technology’s Hydra is a calibration system which ensures LED displays look seamless, working with the company’s Tessera processors to create something the company calls dynamic calibration. Ordinarily, calibration is a lowest- common-denominator approach, requiring that nothing ever gets brighter than the least-capable part of the display. Dynamic calibration lets parts which are being asked to render high brightness trade-off precision for power, accepting a tiny bit of non-uniformity in pursuit of more dynamic range. LED panels also achieve frame rates significantly above those often used for film and TV work, making Ghostframe’s tracking system possible. The speed means the system can switch to displaying something other than the image we’d like to see when the shutter is closed. A second ‘witness’ camera can use markers displayed during that time for accurate tracking; they remain invisible to the initial camera. The same display panels can also show different images for up to four cameras by time-sharing the display, making multi-camera shoots possible in an LED volume. Moiré Anyone who’s seen a live broadcast of a music concert using LED video displays will be familiar with moiré patterns. They appear when LEDs start to line up with the pixels on the TV screen. It’s a problem for studio applications of LED panels, too, and the cleanest solution is generally to ensure those LEDs look small enough that the problem doesn’t arise. That means either a large screen a long way away, which is space-hungry, or a display with a very fine pitch. Video Screen Services, for instance, offers the AOTO CLD27RS – a display with a tiny 1.5mm pitch, making for high resolution and minimum moiré, even in compact set-ups.

AGAINST THE GRAIN Gemini 1x1s (above) were used to light the entirety of a video that promoted them

“It’s difficult to compare lights of different technologies, but Aputure’s new monster should snap at the heels of 1800W HMIs”

lights and battens, equally at home in film, TV or live events. The well-known Titan Tube is now also available in a smaller format, which the company calls Helios – rated at 36W compared to the Titan’s 48W. Brightness is necessarily lower, as is pixel count, but it has the same combination of emitter colours found in the full-power Titan. Including mint and amber helps avoid that sparse spectrum, with amber emitters particularly helpful when creating warm tones intended to flatter human beings, and mint helping out in the notorious gap between blue and green LED emitters. These are all useful, but there’s always a need for sheer illumination. We can’t reasonably discuss LEDs in late 2021 without mentioning Aputure. Absolute power is a desire the company has been fulfilling with its Light Storm series: power creeps up from 120W through to 300W, 600W, and soon a hefty 1200W. The 1200D is not quite

the first such LED on the market, but for people used to the hyper- popular 600D, it’s welcome. It’s difficult to compare lights of different technologies, but Aputure’s new monster should snap at the heels of 1800W HMIs, given it enjoys efficient parabolic reflector options. No price has been announced, but if it follows the pattern of previous releases, it’ll be less than twice the cost of the 600D, which goes for £1930. The 1200, then, is likely to be less than half the price of an M18 and almost as powerful. Conceptually, the Aputure 1200D is simple – a point source – and it’s an irony that the engineering required to build it is hard enough that comparatively complex LED video panels beat it to market. The fact both are becoming mainstream is a testament to much effort; it’s also an open question as to what comes next in a field of technology that, so far, has enjoyed a constant stream of firsts.

59. NOVEMBER 2021

Powered by