CRT Displays

The top chart shows the gray scale of the RCA F38310 HDTV relative to its color temperature at various levels of intensity, or brightness (20 IRE is dark gray; 95 IRE is bright white). As you can see, the gray scale as set by the factory, in the most accurate menu setting, measures 10,510 degrees Kelvin with dark images and leans more toward blue with brighter images. After making adjustments using the Philips PM 5639/00, the gray scale measures within 70 degrees of D6500, the accurate setting, across the entire range. The bottom chart shows the gray scale (or color temperature) relative to the color points of the display's red, green, and blue phosphors. The gray scale is very blue before calibration and is just about on-target afterward. The color phosphors are a little outside the SMPTE standard. The light output was approximately 31 foot-lamberts after setup. The display has fair DC restoration. The F38310 has a good color decoder, leaning toward red, and displays at least 500 horizontal lines (per picture height) with NTSC sources.—RW