Plasma in a Sun Room
I'm thinking about getting the Panasonic TC-P55VT30, but I'm concerned about any plasma TV's ability to deal with the brightness of this room during the day. On the other hand, also important is off-axis viewing, which is a plasma strength and an LCD weakness. Will the plasma wash out during the day even with the blinds closed due to the seeping/indirect sunlight? If so, what LED-LCD would you recommend, since I assume all plasmas would have the same issue? If there is a plasma that would not suffer this issue, I would welcome that name also.
From your description, it seems to me that you won't have a problem with a plasma if you close the blinds during the day. Plasma TVs are certainly not as bright as LED-LCD TVs, but they aren't terribly dim, either; I've seen plenty of plasmas look just fine without washing out in the presence of low to moderate indirect ambient light.
The bigger problem is reflections in a plasma's shiny screen. With enough ambient light, you can see objects in the room reflected in the screen during dark scenes, which can be quite distracting. However, while LCD TVs have traditionally had matte screens, most higher-end models now have shiny screens as well, which is a side effect of techniques used to make the blacks deeper. Thus, LCD no longer has a big advantage in this regard. Speaking of screen reflections, LG introduced a new plasma at CES this year, the PM9700 (profiled here), which features a matte screen to address this problem.
Given that off-axis viewing is important to you and you can block direct sunlight, I think you'll be fine with a plasma. The TC-P55VT30 is an excellent choice, though the ST30 is nearly as good for a lot less money. The biggest advantage of the VT30 is its ability to display 24fps (frames per second) Blu-ray movies at 96Hz, which looks smoother than playing them at 48 or 60Hz as the ST30 does. The VT30 also exhibits slightly deeper blacks, comes with one pair of active 3D glasses, and is THX and ISF certified, though the ST30 performs very well without these certifications.
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