Samsung PN58C8000 1080P Plasma

I was a big fan of Samsung's 2009 1080p plasmas, especially the 650 series and above that included a very cool color management system. However, as much as I liked them I had some reservations. First, even after calibration the grayscale tended to go bluish at the very low end. Second, despite the presence of an gamma preset with several options, the gamma response was not linear regardless of which preset you selected. Thus, I was anxious to see what, if any, improvement Samsung had made with the 2010 panels. I am pleased to report that they have gotten better in both areas and improved the already quite good black level as well.

Black Level, Peak Output, and Contrast

After optimizing Brightness, Contrast and Gamma, the Samsung plasma I worked on had a black level of 0.007fL. This is a little over half of last year's B650 model and this years' G-series Panasonic and just slightly higher than this year's V-series Panasonic. I was able to get achieve the SMPTE-recommended 35 fL of peak output for an on/off contrast ratio of approximately 5300:1. This takes the Samsung's black level performance from very good to close to state of the art among current production plasmas. It is still not in the Kuro league, but it is now is nearly as good as this year's best Panasonics.

For peak output, I selected Movie mode and left it at the default 95 Contrast, 15 Cell Lighting. 35 fL is quite adequate for well-lit rooms, and much higher than that I find fatiguing in dim environments. You can, of course, get more light output from the panel by selecting the Dynamic or Standard Modes, but then you lose the phenomenal color accuracy that the panel is capable of.

Grayscale Tracking

Grayscale tracking indicates a display's ability to produce a neutral shade of white from the brightest whites to very dim grays. This is arguably the most important aspect of a display's color performance, because without a neutral grayscale, all colors will appear unnatural.

Samsungs always ship from the factory with a very blue grayscale preset. Fortunately, Samsung also includes both a user-selectable preset that is reasonably accurate and also provides the tools necessary for a custom grayscale calibration located conveniently in the user menu. First, I measured the default Standard grayscale preset, which is shown below.

As you can see, the Standard preset's grayscale is very blue. The average Delta-E (the standard metric for color error) is 21, which is much too high. SMPTE's error tolerance is 4 or lower. THX specifies 3 or lower.

One of the truly great calibration tools for this year's model is a full 10-point white balance adjustment. This means that instead of having just two sets of RGB controls—one for the top end of the grayscale and another for the bottom end, the Samsung 7000-series and above include the optional ability to adjust RGB at 10 separate points throughout the grayscale. This results in a much more linear response, especially at the low end where I was able to calibrate out the drift towards excessive blue that I saw in the 2009 B650.

Compare this to the post-calibration results for the 2009 B650, shown below.

From 30% stimulus on up, the two are almost indistinguishable. However, below 30% I was able to get a significantly better result on the C8000, and this is due entirely to the 10-point white balance adjustment. Instead of having a single RGB Offset control, I was able to adjust 20% and 10% independently.

Color Accuracy

Much like the grayscale tracking, for accuracy of the primary and secondary colors, this Samsung includes both a reasonably accurate preset (Movie) and the tools to make it even better through custom calibration.

As with all Samsungs, the Movie mode is by far the most accurate preset. Nonetheless, a custom color calibration can substantially improve upon the Movie mode. Here are the post-calibration results.

Samsung's truly great built-in color management system (CMS) makes getting nearly perfect color a snap for those with the tools and training to use it. To use this feature, you must go into Color Space in the Advanced Settings menu and select Custom. This brings up the controls for the CMS. From here you can adjust the amount of RGB in each of the primary and secondary colors.

With a CIE94 average of 0.7, this is essentially perfect color. I have never measured a display that was better, including the Kuro Elites. The Kuro non-Elites are not even close to this good. The bottom line is that without custom calibration, at least in the Movie mode, the 2010 Samsung plasmas offer very good color. With custom calibration, the color performance is world-class.

Gamma

The Samsung plasmas offer 7 different presets for gamma. Although this offers quite a bit of adjustment flexibility, I would have preferred the ability to adjust the gamma at each level of stimulus, rather than simply choosing among a large number of presets. For example, even with the best setting on the 2009 B650 the response sloped downwards—gamma was a little too high on the very low end and much too low on the high end.

The question I am asked more than any other is "What is gamma?" There are a couple ways of thinking about gamma. Perhaps the easiest is that it is that part of grayscale performance that has to do only with the luminance of white. As the signal level increases, we want the display to produce a neutral color of white AND we want the brightness of white at a certain level for each level of stimulus relative to peak output. In this way, gamma is to the grayscale what color luminance is to primary/secondary color accuracy. Another, more technical, way to think of gamma is that it is a numerical expression of the relationship between the intensity of the signal input and output. There is a prescribed relationship between these and this relationship is expressed numerically. Ideally gamma should be in the 2.2-2.35 range. Higher than this and the image will lose shadow detail and appear "contrasty". Lower than this and black levels will be elevated and contrast and image depth will suffer.

First, see the chart below. This shows the best gamma response I was able to get with the 2009 Samsung.

Next, we see gamma response I was able to achieve with the C8000. Unlike the grayscale controls, Samsung did not add new adjustment flexibility. Rather they simply made the existing tool work much better.

Other than a slight dip at the top end, this gamma is nearly ideal.

User Menu Settings

For the best image quality use the following settings:

• Mode: Movie
  Color Mode
• Cell Light: 15
  This adjusts the output of the plasma cells and has an effect on overall image brightness. Adjust this together with contrast to get the desired peak output.
• Contrast: 95
  White Level
• Brightness: 46
  Black Level
• Sharpness: 10
  As you can see, Sharpness should be turned down considerably from its default setting. 1080p plasmas have all the native sharpness one would want. The sharpness circuit generally just adds noise and ringing along light/dark boundaries to give the illusion of more detail. In fact, using it in most cases makes the image less detailed. This adjustment is a legacy feature from the days of analog displays. I wish that manufacturers would just stop offering it altogether.
• Color: 50
  Color intensity
• Tint: 50/50
  Hue of the secondary colors
• Gamma: -2
  See the discussion above of gamma
• Color Tone: Warm 2
  Grayscale preset
• Digital NR: Low
  Put this on low the clean up lower quality sources without sacrificing detail
• HDMI Black Level: Low
• Size: ScreenFit
  This sets the panel to map pixels 1-for-1 without any overscan or internal scaling. Ideal for Blu-ray and 1080i broadcast sources, this setting offers the sharpest image. It also includes a nifty feature that allows the user to adjust the image position to avoid digital noise that may appear at the edge of the screen when no overscan is present.

Subjective Impressions

I loved the image that this display produced. The very low black level, excellent gamma response, and nearly perfect color accuracy and grayscale tracking imparted an extremely vivid, detailed, and natural image with a surprising amount of depth and realism. Plasmas from different manufacturers each have a house "look" that cannot be captured with measurements alone. Samsung plasmas have always looked to me like like very sharp CRTs. They have a natural, less digital quality than the Pioneers and Panasonics. I cannot imagine anyone not being thrilled by the quality of the image that this panel provides. Plasma technology offers all of the image quality of LCDs without the problems LCDs have with viewing angle and motion artifacts. Plasmas also offer larger screens at a lower cost.

Problems

I ran into no significant problems with this display. Working on it was a joy. Some people report a buzzing sound. I heard none on this unit and neither did the client.

Comparisons and Conclusion

I recently calibrated a 54" G-series Panasonic, and I preferred the Samsung C8000, though it is considerably more expensive. The grayscale tracking in each was similar, which is to say excellent. In THX mode the Panasonic's color was nearly as good as the Samsung's. However, the Samsung's gamma response was much better and the black level was lower. The Panasonic G's gamma is reasonably linear, but too low. I haven't spent enough time with a V-series to make any judgments about it, but its black level is reportedly even lower than the Samsung's. I haven't seen an LG at all. However, of the 2010 flat panel displays I have spent some time with, none look better than the Samsung PN58C8000. If I were buying a plasma today, this is the one I would get. Highly recommended.