Yamaha DPX-1300 DLP projector Measurements

Testing and Calibration

Measured using the multiburst patterns on the Accupel HDG-3000 test-pattern generator, the Yamaha's luminance response with a component signal at 720p held up to 37.1MHz (though it appeared to be well down in level at this frequency.) At 1080i, however, the component response was good at 18.5MHz, but completely absent at 37.1MHz. With a 480i component input, the highest 6.75MHz multiburst was noticeably reduced in level. The same was true of the highest 13.5MHz burst in 480p component, though to a slightly lesser degree.

406Yamaha.5.jpg

With an HDMI input at 720p, the luminance response holds up strongly to 37.1MHz. In fact, the response there was nearly textbook. The HDMI 1080i response holds up to 18.5Khz (though it's a bit uneven there), but is well down in level at 37.1MHz. At 480i, HDMI, the top 6.75MHz response is still evident. The 480p HDMI response at 13.5MHz is still good, though slightly reduced in level.

In all cases the color response was not quite as extended as the luminance, but in no case was it rolled off enough to result in problems in normal viewing.

In nearly all cases, the most accurate setting of the Sharpness controls was full off, with one significant exception. For 720p HDMI (but not component) the AccuPel sharpness test pattern looked best with the Sharpness Gain on 1 and the Sharpness Type on 14. With other resolutions the effect of small increases in the Sharpness Gain control (to perhaps 1 or 2) and Sharpness Type (to 14 or less) was relatively subtle with normal program material.

With an HDMI or component input of any supported resolution (480i/p, 720p, 1080i) the Yamaha's overscan measured 1.5% or less on all sides.

On the DPX-1300, the factory color points in the Standard setting of the Color Adjustment control were actually very close to the correct coordinates—about as close as in any other projector I've measured. Attempts to fine tune these points with the WRGB and WRGBYCM modes proved tedious and ultimately of little benefit, at least on our sample of the projector (I had more luck with them on the DPX-1200.) The red control moved the color point the most, the blue and green controls very little. I ultimately chose to stick to the Standard setting for my viewing tests.

In all three modes of the Color Adjustment control the color temperature settings may be individually adjusted for each input. But the settings for various source resolutions are limited to two groups: 480i/p (standard definition) and 720p/1080i (high-definition.) You can choose different settings for the two groups, but not for each resolution within each group. In other words, you can choose one setting for 480i/p and another for 720p/1080i.

Out of the box, the 6500K +/-0.00 setting of the color temperature produced a result very close to ideal. Even the x/y coordinates of each point on the CIE chart came as close to the correct D6500 setting as I would expect to see with a full calibration. But after about 200 hours of use, the lamp had lost enough red that a change to a setting of 6200K +/- 0.000 proved much more accurate. The Before curve in the accompanying chart shows the 200-hour reading in the 6500K +/- 0.00 setting; the After shows the readings obtained at 6200K +/- 0.000. The x/y coordinates were within +/-0.004 of the standard from 30 IRE to 85 IRE.

As an example of what these numbers in the Yamaha setup menu mean (XXXXK +/-0.XXX), the Yamaha sets the color temperature in the user menu by means of a graphical grid with adjustments in two dimensions. The XXXXK adjustment sets a specific color temperature number (which, as with most displays, will not necessarily be accurate through the full life of the projector, and the projection lamp in particular.) But, by itself this setting merely positions you on a line on the color chart; Kelvin numbers by themselves designate lines on the chart, not points. The D6500 standard is a specific point on the 6500K line. The +/-0.XXX adjustment moves you to different points along the chosen color temperature line, with plus numbers moving toward green, minus numbers moving toward magenta.

With the proper measurement tools and these two adjustments, the point you arrive at will be very close to the correct D6500 point.

While the Yamaha offers only global color temperature adjustment via this adjustment grid, and not adjustments at the top and bottom of the brightness range, there is an exception to this. For RGB inputs the projector does provide a separate Level Adjustment menu with high and low settings for red, green, and blue. But for component, this Level Adjustment menu provides high and low settings for Y, Pr, and Pb. Performing a calibration with these interactive color difference controls (Y= luminance as a combination of R, G, and B, Pr=R-Y, and Pb=B-Y) is exceptionally tricky, and most calibrators are accustomed to dealing with the more straightforward R, G, and B adjustments. Furthermore, these Level Adjustment controls do not operate on the digital video inputs. So in most cases you're probably better off with a calibration performed by using just the color temperature adjustment grid.

I measured a peak contrast ratio of 3425 (peak white 13.7fL, video black 0.004fL, Studiotek 130 16:9 screen, 78-inches wide, 1.3 gain, iris at mid position, White Peaking on +3, lamp output at 100%, at 200 hours.)

X