Hi David, I am interested in this television, but as I work in the hockey industry, it alarms me to read a review from amazon that reads like this...
"I got this after going through two Sony NX720s and a near top-of-the-line Samsung plasma. The NX720s had flashlighting issues, while the Samsung suffered from ABL, or automatic brightness limiting. Unfortunately, the ST50 suffers from ABL as well. Last year's models apparently got an update that allowed disabling it, but no such option exists on the ST50 yet.
Most viewers won't be affected by ABL, as it only really comes into effect when there's a lot of white or near-white color on the screen, at which point the screen dims noticeably, with whites looking more like grays. Some people have dubbed this the 'hockey effect', since it's going to constantly dim the screen while you're watching a hockey game. Myself, I like to hook up the computer and play movies or browse the web. The moment I put up a window with a lot of white, the screen goes dim."
So as I work in hockey, this doesn't sound like the television for me, but I want to be interested in it. I noticed in your calibration settings that you mentioned something called "Automatic Gain Control." Is this something that might be causing the "hockey effect" talked about above? Thanks for your time.
Review:
http://reviews.cnet.com/flat-panel-tvs/panasonic-tc-p55st50/4505-6482_7-35118300.html
Related products:
TC-P50ST50
TC-P60ST50
TC-P65ST50
Calibration report using these settings:
http://www.scribd.com/doc/87081224/Panasonic-TC-P55ST50-CNET-review-calibration-results
Below you'll find the settings I found best for viewing the Panasonic TC-P55ST50 in a dim room via the HDMI input. Your settings may vary depending on source, room conditions, and personal preference. Check out the Picture settings and calibration FAQ for more information.
http://news.cnet.com/8301-17938_105-9996461-1.html
Calibration notes: Before calibration and review I aged my Panasonic TC-P55ST50 review sample for 100 hours, my standard procedure for plasma TVs. By default the Cinema setting produced the best picture, although its grayscale was quite green. Since it allowed no adjustment, I resorted to Custom mode. Happily Custom is much better than it was last year and allowed significant improvement despite scant coltrols.
As usual for Custom I disabled settings like Black Extension and Automatic Gain Control (AGC). The former had no positive or negative effect I could discern, while reducing the latter to zero reclaimed detail in white areas. I settled on a gamma preset of 2.6, which came closest to the ideal of 2.2 with panel brightness set to Mid. Compared to the ST30 last year, the ST50's panel easily achieved my target light output of 40 Fl without having to increase Panel Brightness beyond the default Mid; the set seems a good deal brighter this year, even though this year I reviewed a 55-inch model compared to a 50-incher last year (with plasmas, larger sizes are usually dimmer).
The Custom setting's default color and tint is much better than last year's. There's no CMS, but using the simple color and tint controls I was able to get nearly every color under the target delta error, so I was able to keep Color at 46 (as opposed to 32 from last year). For that reason, along with the ability to improve grayscale via the 2-point system, Custom after user-menu-only calibration now offers a much better picture than Cinema can.
On the downside the grayscale is less linear many other TVs'. In particular there was a big RGB balance anomaly at 50, which threw the average gamma and grayscale results for a significant loop. A ten-point grayscale/gamma control might be able to address it.
--Picture menu
Picture mode: Custom
Contrast: +82
Brightness: +60
Color: +46
Tint: 0
Sharpness: 0
Color temp: Warm 2
Color mgmt: Off [grayed out]
C.A.T.S.: Off
Video NR: Off
-- Pro settings submenu
Color space: Normal
W/B high R: +10
W/B high G: 0
W/B high B: +3
W/B low R: +4
W/B low G: 0
W/B low B: -2
Black extension: 0
Gamma adjustment: 2.6
Panel brightness: Mid
Contour emphasis: Off
AGC: 0
-- Aspect adjustments submenu
Screen format: Full
HD size: Size 2
H size: [grayed out]
Zoom adjustments: [grayed out]
-- HDMI settings: [no change from default]
--Advanced picture submenu
3D Y/C filter: Off [grayed out]
Color matrix: HD [grayed out]
Block NR: Off [grayed out]
Mosquito NR: Off
Motion smoother: Off
Black level: Light
3:2 pulldown: On
24p Direct in: 60Hz
Note: This post was edited by its original author added link to calibration results on 03/28/2012 at 1:21 PM PT
Note: This post was edited by its original author Fixed typos in Calibration Notes section. on 03/29/2012 at 6:02 AM PT
Note: This post was edited by its original author modify title on 03/29/2012 at 12:33 PM PT
Note: This post was edited by its original author Updated link to calibration report on 01/15/2013 at 7:12 AM PT

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