Tag Archives: resolution

4K; And Then There Were Two

What does this mean for exhibitors and the audience? More light, and more dark. It seems that each generation of the DLP chip constantly refines the edges of, and space between the mirrors, which refines the amount of “off” – the non-reflecting space – and makes the reflecting segments comparatively more “on”…thus a boost in the dynamic range, or “contrast” spec, which the larger size also adds to. The PR doesn’t list how the 2500:1 contrast ratio is measured, but it is a 25% increase from what Barco prints as their C Series spec of 2000:1, while Christie now specifies >2100:1 full field on/off. Presuming that everyone is using the same measuring technique, with more light, larger screens can be lit. [Side note: Barco’s spec says that it takes 32,000 BTUs per hour to get that kind of light from a 6.5kW zenon bulb, which has an average life of 900 hours. No one is saying that this advance will imply less electricity or longer life for the bulbs.]

4K is a nice number, but no one ever walks out of the theater saying that there were too few pixels. There are those who point out that the constraining factor in quadrupling the pixels from 2K to 4K is actually the lens, which can’t resolve that much resolution anyway. 

Because of the increased area, more light will reflect off the same number of micro-mirrors. Therefore, 3D should get the largest noticeable boost – 5% was the number that one OEM used. In a universe that is starting from 10 candela/meter2, 5% more light would be a greater benefit for a 3D audience than the same higher gain would bring for the 2D audience in a larger auditorium.

So, what does this chip do with a 4K 3D image? It doesn’t. We know that there was surprise when Sony announced that they were creating 3D by breaking up their LCOS imager into two 2K sections, one for each eye’s image. But there doesn’t seem to be any loss for orders after exhibitors saw the results.

TI is also keeping a 3D image at 2K, but they make the point that with this release “we will use the entire imager to display 3D in order to pass the maximum amount of light which is needed for 3D display. In other words the 2K image will be scaled up to 4K. We say, All the Imager, All the Time.”  

It makes sense to go for the increase in light, however small it is. The other part of the equation is the amount of bandwidth that can be pushed into the TI cards, but that is more math than is comfortable in this commentary on a simple press release.

References:

23 degrees…half the light. 3D What?

Laser Light Engines gets IMAX funding– Putting Light on the Subject

Optical Efficiency in Digital Cinema Projectors

3Questions – Laser Light Engines