JVC LT-42P300 LCD HDTV Review - Color Accuracy

Color Accuracy Summary
• Color temperature very good • RGB accuracy had some problems with peaking • Color Gamut better than average • Testing done with DisplayMate software
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Color Temperature (9.79)

Anything that emits light produces a particular temperature of light, for example stars range from blue hot to cold and red. Similarly an HDTV has a color temperature, which sould ideally sit around 6500 Kelvin (K). As important as the actual temperature, however, is how steady the color temperature is, which is what we look at in this test. Below you can see a graph of the JVC LT-42P300's color temperature plotted across the greyscale, starting with the brightest white and going all the way down to black. Deviations above the line indicate the temperature is getting hotter and causing a bluish cast, while those below the line indicate a dropping temperature that can cause a yellowish or reddish cast.

You can see from the graph above that the JVC LT-42P300's deviations are minor, but the graph below makes this even more clear. Here we plot each of the data points on a color space. The important feature is the red circle, which indicates the range within which our eyes can't detect a difference in color temperature. You can see clearly here that the JVC LT-42P300's variation in color temperature fall almost completely within this circle, which is exactly what we want to see, and the reason for the LT-42P300's excellent score in this section.

RGB Curves (6.33)

Every color that you see on your HDTV is produced by mixing various amounts of red, green and blue light. As such the accuracy of these colors is paramount for determining the color accuracy of the television. Below you can see graphs for the JVC LT-42P300's red, green and blue plotted across the intesity scale. What we're looking for here are smooth, slightly concave curves that increase steadily across the range of intesities.

You can see immediately that the JVC LT-42P300 has some problems here. All three colors exhibit some amount of what we call peaking, which is indicated by the plateaus at the top end of the curves. What this means is that the LT-42P300 is struggling or completely unable of producing differences in the colors at the high end. This peaking can mean that you lose fine detail in bright colors. You'll also notice that the blue curve never falls completely to zero. We also noticed that the LT-42P300 produced some artifacts, in particular false contouring in certain situations, which can cause gradiations to appear on the display that shouldn't be there. These problems combine to produce a below average RGB score for the JVC LT-42P300.

Color Gamut (6.45)

In order to ensure that the colors you see on the television are the same as the colors everyone else sees and the colors the producer of the content wanted you to see all televisions must adhere to the international Rec.709 standrd for color gamut. In this test we look at how well the HDTV does this. Below you can see the color gamut for the JVC LT-42P300 graphed against this standard.

As you can see the LT-42P300 had a few problems matching the standard, in particular in the blues and greens. What this means is that these colors will be slightly different than what the content producer actually wanted you to see. We have to say, however, that almost every HDTV we've reviewed has done a less than impressive job of matching the standard. The LT-42P300's performance is actually significantly better than average. For those who want the raw data you can see the measured and ideal color coordinates and the error in the table below.