LED: Projection Perfection
by Brent Butterworth
A new generation of projectors promises to fix every problem we ever had with video projection. Based on the time I’ve recently spent with a couple of these machines, it looks like the promises have been fulfilled.
These new projectors use LEDs as a light source instead of the UHP lamps that other projectors use. LEDs offer all sorts of advantages over lamps. The biggest one is that LEDs never need replacing—unlike lamps, which need to be replaced every 2,000 to 3,000 hours. That means a huge cost savings over the course of several years. Manufacturers rate the lifetime of the LEDs anywhere from 20,000 hours to practically forever (even though they’re all using the same LEDs).
Supposedly, the performance of LEDs doesn’t change much over time. But lamps start to dim and shift color after about 1,000 hours, necessitating frequent readjustment of the picture controls.
LEDs can also deliver deeper black levels and better contrast. Many lamp-based projectors use an automatic iris to get deep blacks; the iris closes down automatically during dark scenes to make the blacks darker. Problem is, you can often see the iris working. LEDs don’t need the iris, because they can be dimmed almost instantly to any level. Based on what I’ve seen so far, the speedy operation of the LEDs can indeed eliminate the “pumping” and flickering you sometimes see with auto iris mechanisms.
That’s a lot of advantages, right? Well, there’s more.
Because LED projectors use separate red, green, and blue LEDs instead of a white lamp shining through a rotating color filter wheel, the “color fringing” effect you see on most DLP projectors is eliminated. And because LEDs can deliver more intense, saturated color, you can set the projectors up for an ultra-vivid picture. Some will say it’s unrealistic, but I’ve grown addicted to the look after living with it for a few weeks.
This first generation of LED projectors warms up in 40 seconds, only about a third of the time it takes for a lamp-based projector to fire up. And when you shut them off, they go off instantly because unlike lamps, they don’t need to be cooled down gradually by a fan.
The time I recently spent with the Digital Projection M-Vision Cine LED convinced me that LED is the wave of the future for video projection. It’s a shame that only a small handful of people are getting to enjoy the rich hues of the Winter Olympics on an LED projector, but I’m glad I’m one of them.
