Review af Samsung PN50C7000 med dårligt SORT?

Samsung PN50C7000 calibration report/review

Earlier this week, I met with Chris from Cleveland Plasma to take an in depth look at the new Samsung PN50C7000 3D capable plasma and compare it’s performance to a couple of other sets I had calibrated. The C7000 is a perfect example of the new breed of sleek and slim plasmas, and it’s profile looks fantastic from any angle. It seems to pick up an average amount of glare compared to other plasmas, with the reflections perhaps a bit more diffuse than on the LG plasmas.

Though I did not have an opportunity to see the C7000’s 3D processing, I wanted to see just how good it’s core performance was. Unlike Samsung’s UN46C7000 LED LCD that I reviewed recently, the picture mode is selectable even while in 3D mode, so you can enjoy a more accurate picture in 3D.

I took measurements of different picture modes before making any changes. Standard mode (not shown) was not very watchable in my opinion, with a very blue/purplish cast to the white balance, poor gamma that will give brightly lit faces a clayface or caked on makeup look, and a low light output of only 19.4 fL. Samsung added a new mode called Relax, and it’s performance is shown in attachment 1. Relax’s measurements suggest a more watchable picture than standard mode, though the white balance is still somewhat purplish and the colors are pushed. Movie mode (attachment 2) shows pretty good performance overall, though the color gamut is a bit narrow and the green color luminance is pushed. Overall, movie mode appeared to be a great starting point for calibration.

The C7000’s secret service menu was sparse, with little of interest to calibrators that I could find. Thankfully, in movie mode a fantastic selection of advanced calibration adjustments is available. Samsung added a properly functioning 10 point white balance/gamma adjustment, which can be used with the proper test equipment to fine tune the performance. The C7000 also includes a complete, properly functioning CMS (Color Management System) adjustment, gamma presets, and a 2 point white balance control that can be used in conjunction with the 10 point adjustment. The shadow detail adjustment I saw on the UN46C7000 was missing. Fortunately, it’s shadow detail was good enough already that I felt no need for the missing adjustment. There is also a skin tone adjustment that makes on the fly adjustments to make skin tones more or less red.

The C7000, like many other Samsung sets, has a switchable black level when fed an HDMI RGB colorspace signal. However, it has color decoding discrepancies with RGB colorspace that are not there with the more common YCbCr. That means some video games and DVI sources may not have as accurate color as Blu Rays and other HDMI video sources.

1080i and 1080P resolution in dot by dot mode was perfect and strong. Black level, measured with a low light sensitive colorimeter profiled off the Eye One Pro meter on this TV, measured .033 fL. Black had a very slightly greenish cast. The modified ANSI contrast ratio measured 958:1. The C7000 could be calibrated to be nice and bright; I calibrated peak white to match 2 other plasmas nearby to facilitate a three way comparison at around 45-47 fL, though it could have easily gone higher.

The after calibration measurements are shown in attachment 3. The 10 point adjustment worked great to make the white balance and gamma nearly perfect. Likewise, with the help of the CMS adjustment, colors matched the HDTV standards to a degree that is rarely, if ever, seen in other sets.

Te first thing that jumped out at me as I put some familiar 1080P/24 Blu Ray material on was the vibrant color. Initially, it overshadowed everything else; those carrots in the DVE restaurant scene jumped right out at me, and a few seconds later when the flesh tones came into the scene they looked extremely rich but a little too ruddy.

Shadow detail looked good; compared to some other sets the shadow detail may appear a bit hard to see, but in my opinion it was balanced perfectly. Shadow detail was noticeably better than on Samsung’s previous models before they implemented the 10 point adjustment. Resolution, detail, smoothness, and stability were all great; there was no annoying graininess or pumping in the picture. However, black level was noticeably not inky black. From the material I looked at, it appeared that 1080P/24 was displayed at 60 Hz rather than a multiple of 24, though on most scenes it was hard to tell. While the image was without question very impressive, I decided I should recheck my CMS calibration to see if I could find an explanation for the explosive colors.

Using the set’s color isolation controls, I discovered that the C7000’s color decoding changed a bit with picture level. I redid the CMS, starting with a lower overall color setting, and found that eliminated the issue. I rechecked the demo material, and things looked very similar; though I felt the flesh tones were a little better controlled this time around. I felt that the flesh tones at this point, though still overly ruddy, were reasonable enough that I did not want to sacrifice accuracy or overall color to try to make them more to my liking. The skin tone adjustment, which I left at the neutral position, can be used to lessen the sunburnt look while minimizing the compromise to other colors.

I feel that Samsung may be doing a bit of behind the scenes color processing that will make the C7000 stand out relative to the competition. While I feel it is a bit overdone, I could understand many people preferring it’s vibrant colors over a more accurate but comparatively bland picture. In fact, I think it’s just the look that will draw people to it. Fortunately, there’s enough color adjustments that if you feel it is a bit overdone, as I did, it is possible to bring them more in line with your taste.

Since I had two other recently released plasmas nearby that I had just calibrated, I couldn’t resist doing a comparison between the C7000, the LG PK750, and the Panasonic G25. While screen size varied, I did calibrate all of them to a similar light output. This particular LG PK750 was not the sample I originally reviewed; it was the one on which I was able to successfully adjust it’s 20 point white balance/gamma adjustment. That will not be possible most of the time unless LG makes a correction in it’s adjustments, and it gave this particular PK750 an advantage. Please see my review of the PK750 for the complete explanation.

With a 0% black signal, the G25 had the darkest, inkiest blacks in a dark room. The PK750’s blacks were neutral toned but quite a bit lighter than the G25. It is possible, however, that as the G25 ages it’s black level would be more similar to the LG and Samsung because of it’s allegedly rising black level. The C7000’s blacks looked very close to the PK750’s, though a bit more greenish. With the lights on, the G25 suppressed reflections better than the PK750 or the C7000. Looking at the demo material on the DVE Essentials Blu Ray, I saw excellent skin tones on both the G25 and PK750, while complexions looked a bit too red on the C7000. There was a textured look on the PK750 that was only barely noticeable and was probably a byproduct of some edge enhancement. All three sets seemed to handle pans and motion about the same; there was a slight jerkiness that seemed to suggest none of the sets were displaying the 1080P/24 signal at a multiple of 24. The G25 and PK750 had good depth and pop, while the C7000 had richer, more vibrant color. The G25 had neutral toned but slightly overemphasized shadow detail. The PK750’s shadow detail was a bit less neutral with a slightly greenish tone, but also appeared a bit overemphasized. The C7000’s shadow detail was probably the most neutral when both color tone and visibility were taken into account. The G25’s image seemed just a tiny bit crisper.

Overall, I think the C7000 is a very good set with textbook measurements. It's color may be too vibrant for some while the cat's meow for others; and it's black level is not as dark as I would prefer, but in every other way it is a stand out set.

UPDATE: Please see this post for a possible explanation for the higher than expected black level measurements.

< =""> Attached Files

	Sam PN50C7000 bef relax.pdf (179.8 KB, 149 views)
	Sam PN50C7000 bef movie.pdf (174.7 KB, 108 views)
	Sam PN50C7000 aft movie.pdf (169.8 KB, 122 views)

It was breaking in at a high contrast level immediately prior to calibration. Calibration was done at a contrast level in the mid 80's (going by memory). I was not aware of this issue, so I made no attempts to cool it down for that long prior to measuring black level. I do give the sets a few minutes rest to reduce image retention before taking the measurement, but it sounds like it may need a lot more.
Thanks for pointing this out; it could explain a lot.

BTW, I didn't hear any buzzing.