PLV-Z3000 Color Tempurature Measurements (default) for Pure Cinema mode

Posted on December 7, 2008 by Art Feierman

PLV-Z3000 Color Temperature Measurements (default) for Pure Cinema mode

Color Temperature
The defaults were a bit cool (more blue/less red) - ideal is 6500K:
30 IRE	7181K
50 IRE	7617K
80 IRE	7244K
100 IRE	6952K

Effect of Zoom Lens Positioning on Brightness

Measuring Brilliant Cinema (with iris fixed, lamp on full):
Center of Zoom range	618 lumens
Wide-Angle Zoom (largest image)	714 lumens
Telephoto Zoom (smallest image)	443 lumens

Measuring Brilliant Cinema (with iris fixed, lamp on full): Center of Zoom range: 618 lumens Wide-Angle Zoom (largest image): 714 lumens Telephoto Zoom (smallest image): 443 lumens

The drop off in maximum telephoto is (as is typical for the projectors with 2:1 zoom lenses), rather significant. Most people shelf mounting will need their zoom lens set somewhere between mid-point and full telephoto.

That also means that the loss of brightness by going to a larger screen isn't really a big factor, from the same mounting distance, the larger the screen, the brighter the projector's lumen output.

Consider: If you have a 100 inch screen at 20 feet back, you are in full telephoto. Got to a 150 inch screen from the same distance, and the lens is at the mid-point. The projector's brightness increases 39.5% (443 lumens to 618 lumens).

The 150 inch screen surface is 2.25x the surface of the 100 inch. Basically, the larger screen brings a drop in average lumens (or ft-lamberts), of 55%. The brighter image from the mid-point lens position, increases brightness by 39.5%. You still have a dimmer image with the larger screen but almost half of the expected difference, based on size, is offset by the brighter lens position.

With a 100 inch screen, the calibrated Pure Cinema mode, with dynamic iris, and auto lamp dimming on, (367 lumens) produces 12.4 ft-lamberts with low life on the lamp, and the zoom in the mid-point position. 12 ft-lamberts is the movie theater (SMPTE) minimum standard for brightness.

OK, that may be very confusing at first read, but should be helpful for those with flexibility in placement, who want to consider a larger screen.