Panasonic TH-42PX25 Plasma HDTV HT Labs Measures
• Full-On/Full-Off Contrast Ratio: 813:1;
ANSI Contrast Ratio: 780:1
• Measured Resolution with the Leader LT-446:
480: Out to the limits of DVD
720p: 590 (per picture height, RGB input only)
1080i: Out to the limits of the 1,024-by-768 panel with the RGB input and 550 (pph) with the component input
• DC Restoration (poor, average, good, excellent): Good
• Color Decoder (poor, average, good, excellent): Good
• Measured Color Points:
Red Color Point: x=0.658, y=0.332
Green Color Point: x=0.279, y=0.649
Blue Color Point: x=0.155, y=0.071
The left chart shows the TH-42PX25's gray scale relative to its color temperature at various levels of intensity, or brightness (20 IRE is dark gray; 100 IRE is bright white). The gray scale as set by the factory, in the warm color-temperature mode and the cinema picture mode, measures slightly warm across the gray scale. After making adjustments using the Photo Research PR-650, the gray scale measures slightly cool with darker images but fairly close to D6500, the accurate color temperature, across the rest of the range.
The right chart shows the gray scale (or color temperature) relative to the color points of the display's red, green, and blue phosphors. These are somewhat close to those specified by SMPTE. Red is slightly oversaturated, while green is oversaturated to a greater extent.
Using a full-field 100-IRE white (21.95 foot-lamberts) and a full-field 0-IRE black (0.027 ft-L), the contrast ratio was 813:1. Using a 16-box checkerboard pattern (ANSI contrast), the contrast ratio was 780:1. The TH-42PX25 produced 39.51 ft-L with a 100-IRE window (it's normal for a plasma to have more light output on a window versus a full-white field).—GM