Video Projectors

Summary
• Calibration significantly improved the HD8000's out of box performance from fair to good. • The resolution was very good over HDMI but less impressive in component. • The Optoma is capable of relatively high light output, but its black level and peak contrast ratio are only fair by today's best standards.

Details
Color
Out of the box, the Warm setting of the color temperature control was cooler than ideal, but at a bit over 7000K it was still better than many displays we have reviewed (Fig.1). After calibration, it was closer to the ideal, though still a bit high in the mid brightness region and at the very bottom end (Fig.2).

Fig.1

Fig.2

Even if the color temperature (Figs. 1 and 2) is 6500K across the board, that's only part of the job. 6500K by itself only defines a line on the CIE color chart. The specific point on that line we are aiming for is known as D6500 (or sometimes D65). If the red, green, and blue readings (Figs. 3 and 4) are precisely overlaid at the 100% mark from left to right, that indicates we are at the D6500 white point over the entire brightness range—or at least from 20 IRE to 100IRE (few measurement tools, and not even our Photo Research PR-650, will produce accurate readings in the darkest grays below 20IRE). As you can see, on the HD8000 the three colors weren't that well lined up before (Fig.3). The post-calibration result (Fig.4) is closer—acceptable but still somewhat short of the best we've seen.

Fig.3

Fig.4

Fig.5 shows the color space defined by the Optoma (the white triangle). It's a little wider than the ideal (the black triangle) but definitely better than most, particularly its green point, which is not excessively saturated—a common failure.

Fig.5

Resolution
The Optoma performed well on the luminance (black and white) tests; it was down in response just slightly at the maximum burst frequencies of 37.1MHz for 1080i and 720p and 13.5MHz for 480p. The response at 480i easily met the requirements of that format (6.75MHz). The HDMI chroma (color) response was good at 720p and 480i/p and down noticeably at 1080i—but not enough to visibly affect the image.

The component response was not nearly as good, with little or no visible luminance information at either 1080i or 480i at the maximum frequency, though good up to at least 18.5MHz for 1080i.

The one pixel on, one pixel off vertical line in a sharpness pattern was good, but noticeably shy of the pristine sharpness I've seen with other (more expensive) projectors. The Sharpness control was peculiar. No setting completely eliminated a slightly gray shadow on either side of the sharpness pattern lines. While settings below 3 noticeably softened the pattern when viewed from near the screen, they usually looked best on normal program material. The Sharpness control had little or no effect on 480i material. The Edge Enhancement control, however, added distinct white edges to both horizontal and vertical lines at any setting besides 0 (off).

Contrast
With the settings shown above, and approximately 35 hours on the lamp, I measured a peak contrast ratio of 1,713:1 (18.84 foot-Lamberts peak white, 0.011fl video black) on my 1.3 gain, 16:9, 78-inch wide, Stewart Studiotek 130 screen). It was possible to raise the Contrast control well above the level indicated in the "Settings" section, but doing so produced a pronounced pink tint on the test pattern I use for setting the peak white level (the reverse gray scale in chapter 12-14 of Digital Video Essentials).

Overscan
With the overscan control set to zero, there was no overscan with an HDMI source at 1080i, 720p, or 480i/p. In component, the maximum overscan was 1% (at the top of the image in 480i).