The ST50 is available in four sizes: 42" (TX-P42ST50), 50" (TX-P50ST50), 55" (TX-P55ST50) and 65" (TX-P65ST50).
DESIGN & BUILD
But while the ST50 may have gained a clear plastic frame, it has lost an HDMI port, as Panasonic's 2012 model has three rather than four HDMI connections. We would have preferred it the other way round, to be honest. Apart from the vanishing HDMI port, the connections haven't changed, and still include two USB ports, an Ethernet port, built-in Wi-Fi, an optical audio out, and component and composite video connections.
The remote hasn't been updated. It's still as massive as ever, but its chunky backlit keys make it easy to use. That said, a bit of a facelift wouldn't do it any harm.
The ST50 has the same multimedia functions as Panasonic's other 2012 TVs.
The Viera Connect smart TV platform offers access to all kinds of connected services. There are plenty of good-quality apps to choose from, and the platform is practical to use and easy to navigate. You'll find all the usual apps, such as YouTube (with HD video), Skype, Twitter, Facebook and Google Maps, as well as games (although these will set you back about £5!).
The media player is compatible with more file formats than the 2011 version. NTFS-formatted devices are supported (Windows format), so files over 4 GB in size can be played, which isn't the case with FAT 32 devices. Plus, most video containers are played, including AVI, DivX, MP4, MKV, MOV, MTS and M2TS. The only remaining trouble-makers are ISO files (disc images) and DVD/Blu-ray menus.
The black is so deep that our sensor couldn't even measure it. When that's the case, we consider the contrast to be over 5000:1. Needless to say, that's pretty much ideal.
Colours are reproduced accurately (average Delta E = 3), the gamma is well balanced, the colour temperature is perfect (6491 K), display quality is consistent over the panel, and viewing angles are very wide. What more could you ask for?
But there is one slight drawback, as, like all plasma screen TVs, the image does lack a little brightness when viewing in very bright, very well-lit rooms. Plus, the glossy screen doesn't help matters much in those kinds of viewing conditions. It's therefore a TV that's best used in a room where you can control the ambient lighting.
With input lag at 66 ms, hardcore gamers may notice some latency, which could prove problematic in multiplayer games. However, screen responsiveness is very good—as always with plasma screens. We measured the average ghosting time at 6 ms, which puts the ST50 up there with the best.
The Intelligent Frame Creation mode does a great job of keeping things smooth when watching films. Set to its medium level, it eliminated judder and glitches without creating a "camcorder" effect and without affecting image quality.
The ST50 has no problems with clouding. Another great thing about plasma technology is that black levels are perfectly consistent over the screen. Here too, we really couldn't ask for more!
The excellent levels of screen responsiveness mean that there's practically no crosstalk in 3D mode (images for the left and right eyes overlapping and causing interference). Only a few slight overlaps can be spotted in the most highly contrasted images (a white 3D object on a black background, for example), but that's pretty a rare occurrence in most films. The ST50 is therefore on par with the higher-end Panasonic VT50 for 3D viewing.
3D image test cards as seen through 3D glasses (Top: Panasonic TX-P50ST50 / Bottom: Panasonic TX-P50VT50):
One glance at the frequency response graph is all it takes to identify this as a 2012 Panasonic TV. Mediums are amplified to give the impression that the bass is more powerful. The overall effect is flattering, and it's easy on the ears, but it does in turn make high voices less easily intelligible. While that clearly won't be a problem for watching the news or the odd TV show, if someone with a high-pitched voice speaks with a low, bass noise in the background, you may have trouble picking out all the words. For the best results, we recommend you pick up a separate home cinema speaker set.