Samsung UN46B6000 LCD HDTV Review - Blacks & Whites

Blacks & Whites Summary
• Very deep blacks • Bright whites • Excellent contrast ratio • Testing done using DisplayMate Software
	Calibration	Page 4 of 16	Color Accuracy

Black Level (8.0)

When we first measured the Samsung UN46B6000's black level we got a reading of .02 candelas per meter squared (cd/m2), which is incredibly low. We noticed, however, that the UN46B6000's backlight seemed to turn itself down dynamically when an all black screen was displayed, probably a power-saving feature. When we did our tunnel contrast test, however, with black sharing the screen with varying amounts of white we saw the black level rise up to between .10 to .12 cd/m2. Because this better reflects the black level that viewers will actually get while watching content we decided to ignore the black level reading of .02 cd/m2 and go with the lowest number we saw in our tunnel contrast testing, which was .10 cd/m2.

This is still a very good black level for an LCD television. You can see from our comparison chart above that it's significantly better than the JVC LT-42P300, and compares favorably with the Plasma Samsung PN50A760 and the LCD Sony Bravia KDL-52V5100.

Peak Brightness (8.84)

In this test we look at how bright the Samsung UN46B6000 was able to get when displaying a 20% white screen. The Samsung UN46B6000 did very well in this test, posting a peak brightness of 349.20 cd/m2. You can see below that this compares favorably with two other LCD televisions. The Plasma Samsung PN50A760 performed significantly worse, which is one of the trademarks of plasma displays.

Contrast (8.34)

Human eyes are very sensitive to contrast, thus the range of contrast from the deepest black to the brightest white that a television can display tells us a lot about how good the image is going to look. The Samsung UN46B6000's contrast ratio works out to 3492:1. This is an excellent contrast ratio, close to twice the average we see from all the televisions we've reviewed. Below you can see that it far outpaces the JVC LT-42P300 and even though the other two HDTVs put up very good contrast scores the UN46B6000's is significantly higher.

Tunnel Contrast (9.06)

In this test we look at how well the black level of an HDTV holds up as black makes up less and less of the display. This is important because you don't want to see the black level rise dramatically when it's placed against a bright object as this sharply reduces the perceived contrast ratio. Thankfully this isn't an issue with the Samsung UN46B6000 as the black level stayed relatively constant as we go from a 90% black screen to a 5% black screen.

You will notice that there is a sharp rise from the 100% black to 90% black. This is the result of the Samsung UN46B6000's dynamic backlight, which is what led us to adjust the black level in our score above.

White Falloff (6.87)

In this test we look at how well the brightness of whites hold up as we reduce the total percentage of white on the screen. As with the tunnel contrast test above this is important to see whether the HDTV is able to produce a steady contrast ratio. Below is the graph of the Samsung UN46B6000's performance in this test.

You can see that the brightness stays relatively stable throughout until it plummets almost 100 cd/m2 when the HDTV goes from 10% white to 5% white. This is likely the same dynamic backlighting effect that we mentioned in our tunnel contrast and black level tests above. This is a problem because the result is that if you have a very dark scene with just a couple of bright elements you're going to lose a significant amount of contrast. As such the Samsung UN46B6000 puts up a below average score here.

Uniformity (6.5)

The uniformity of the Samsung UN46B6000's display varied sharply between an all-white screen and an all-black screen. With the white screen we saw a small amount of darkening at the corners, but no problems in the center of the display and an overall smooth appearance. With the all-black screen, however, we saw significant brightening at the corners, that extended well into the main display. We also saw blotches of light in the center of the display and along the edges. Edge lit displays like the UN46B6000 actually have their backlights lined along the edge of the display and then bounce them off materials behind the display to try and even things out. It looks like Samsung still needs to do some work in this area.

Greyscale Gamma (8.37)

The Gamma curve is the curve along which a television makes the transition in the greyscale from dark to light. When we first measured the Samsung UN46B6000's gamma curve it came out close to 3.0, which is significantly higher than our ideal of 2.1 to 2.2. Thankfully the UN46B6000 offers a gamma controls that runs from +/- 3. Adjusting this control up to +3 and running our test again we measured the UN46B6000's gamma at a much better 2.47. This is still a little bit higher than we'd like, but is close enough that it shouldn't be a problem.

This is good because a gamma that's too aggressive can reduce the perceived contrast on the display, and as we mentioned in our contrast section above the human eye is very sensitive to this.

Resolution Scaling (8.07)

The Samsung UN46B6000 has a resolution of 1920 x 1080, and supports full 1080p content. The "p" stands for progressive, which means all 1080 lines of content from top to bottom are displayed at once. This is the highest quality of HD content available, although it's generally only available from Blu-ray discs. Most of the content you'll see on your HDTV will come in a different format, and in this section we look at how well the UN46B6000 handled that content.

480p/i (8.2)
This is standard definition content, which comes in two flavors. In both cases you get 480 lines of resolution from top to bottom. This is the standard definition content you get from broadcast television or from DVDs. The Samsung UN46B6000 had some problems with overscan, meaning it cut off parts of the display. In this case it cut off 3% of the content on all sides. Thankfully that was the only major problem we detected, there were no problems with with moire patterns, which can appear in complex patterns, legibility or resolution.

720p (7.5)
This is the lowest resolution of content that quaifies as HD, with 720 lines of content from top to bottom. 720p is used on the internet and sometimes by sports broadcasts. The Samsung UN46B6000 had the most problem with 720p content. There were no oversan issues, but we did notice some cross-hatch patterns that appeared when the HDTV was displaying complex patterns. We also noticed problems with displaying high resolution patterns. The problems weren't so bad that the television was unwatchable, but they were there.

1080i (8.5)
This level of HD content has the same resolution as 1080p, but the 1080 lines of resolution are alternated between two sets of 540 lines and interlaced together, which is what the "i" stands for. Broadcast HD is 1080i because it cuts the signal that has to be sent in half. The Samsung UN46B6000 had no problems displaying 1080i content.