Power-saving in LED VP – Common Cathode LED
Today there are some excellent initiatives and reports geared to reducing carbon emissions generated by cinematic and HETV production:
- The Green Production guide: greenproductionguide.com
- Albert: wearealbert.org
- UCLA Institute of the Environment and Sustainability: https://www.ioes.ucla.edu/project/a-life-cycle-analysis-of-virtual-vs-physical-production-for-film-and-television/
LED virtual production already offers compelling sustainability credentials over location shooting, but powering the LED volume and the HVAC required to handle the excess heat generated, are still areas that need addressing.
Currently the focus on reducing carbon emissions in a LED volume are to do with the fuel used to power the LED tile and the HVAC, and this is quite right. But in doing this we’re focussing on only one side of the equation i.e. de-carbonising the existing power need. We should also be focussed on reducing the power needed. So how do you reduce the power drain of an LED volume and minimise the HVAC required ?
Common Cathode LED tiles
Most LED tiles today use common anode LEDs, but there is a new type of LED that uses a common cathode design. The technological explanation of the differences between common anode and common cathode LEDs is shown below.
In common anode LEDs, the 3 anodes of the R,G, and B emitters (diodes) are joined and powered by the same voltage.
In common cathode LEDs, the 3 cathodes of the R, G, and B emitters are joined together, and the R,G,B anodes are powered by different voltages that deliver the optimum light performance for each.
The short version is that the common cathode design uses less power and generates less heat. When common cathode LEDs are combined with new common cathode driver chips with 3x the performance of previous versions, LED tiles can be created with fewer chips reducing power drain and heat emission still further.
From a sustainability perspective, this is great news for LED VP. So why haven’t you heard about common cathode LED tiles then ?
Well, part of the reason is that its relatively new, partly is down to few people understanding LED component technology (why would they?), but the other part is that if you’re an LED manufacturer that only makes common anode LED tiles, you have a vested interest in promoting what you manufacture today, right ?
Common cathode LEDs and performance driver chips are the way forward for LED VP. If you’re thinking about building a LED VP stage or volume, and you care about sustainability, then you should be insisting on common cathode LED tiles. The added benefit is that these common cathode LED tiles also produce better imagery, and reduce LED failure rates, because of the way the RGB emitters are powered. Currently there is a premium on high performance Common Cathode driver chips, but this will come down over time, and the cost differential would be offset quickly by the reduction in power and HVAC required.
Bendac’s two LED VP tiles – ProCine and ProStudio – are both common cathode LED designs with the high-performance driver chips, and both can reproduce 99.2% of the DCI-P3 colourspace. For more information on our LED VP tiles click here, or to discuss your next project, get in touch with us via the button below!
