Big Screens, Small Prices HT Labs Measures: Optoma
Contrast Ratio: Full-On/Full-Off—1,691:1; ANSI—300:1
Measured Resolution: One-Pixel-On/One-Pixel-Off:
480: 480 (per picture height) HDMI Vert/Horiz: Y/Y
720p: 720 (pph) Comp Vert/Horiz: Y/Y
1080i: 1080 (pph)
Black Hold: Excellent
Color Decoder: Good
Before Cal:
AveDev: 400
MaxDev: 502
Off 6500: 698
After Cal:
AveDev: 163
MaxDev: 621
Off 6500: 85
The top chart is the HD80’s color primaries and secondaries (colored circles and white triangle), as seen on a CIE 1976 chromaticity diagram, versus the SMTPE-specified standards (colored diamonds and gray triangle). The converted x,y coordinates (for comparison to a CIE 1931 chart) are Red: x=0.652, y=0.329, Green: x=0.297, y=0.627, and Blue: x=0.144, y=0.070.
The middle chart shows the HD80’s gray-scale tracking, as in its color temperature (vertical axis) versus its brightness (horizontal axis). The left-most point is an IRE of 20, a dark gray. The right-most point is an IRE of 100, a bright white. The dotted line represents the ideal target of D65, or 6504K. The gray scale as set by the factory, in the Low color-temperature mode and the Cinema picture mode, measures cool with dark images and even cooler with brighter images (blue trace). After making adjustments using the Photo Research PR-650, the gray scale measures much better (red trace). The HD80’s gray-scale tracking before calibration is fairly poor, so it has an AveDev of 400. It has significant wide variations, so it has a mediocre MaxDev of 502. Its entire gray scale averages 698 off 6500K. After calibration, this is all better, although the MaxDev is still fairly poor.
After calibration, and using a full-field 100-IRE white (6.764 foot-lamberts) and a full-field 0-IRE black (0.004 ft-L), the contrast ratio was 1,691:1. Using a 16-box checkerboard pattern (ANSI contrast), the contrast ratio was 300:1. The best contrast ratio and black level were achieved with Brite Mode and ImageAI on and the IRIS set to 16. The brightest image was achieved in the Brite Mode on and the IRIS set to 0. In this mode, the HD80 produced 16.26 ft-L and 0.011 ft-L for a contrast ratio of 1,251:1 (on an 87-inch-wide, 1.0-gain Da-Lite Da-Mat screen).—GM
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