The P46GT30 is endorsed by both the Imaging Science Foundation (ISF) and THX, so it's no great surprise to find it packing both a decent suite of calibration tools and dedicated Professional (ISF) and THX picture presets. Among the set up aids are adjustments for the set's gamma level and a degree of colour management.
There are certainly more fulsome calibration toolsets available elsewhere in the TV world, including on Panasonic's own VT30 series. But so far as we're concerned there's more than enough flexibility here to satisfy a typical mainstream user.
In fact, we'd venture to suggest that any ISF-certified TV will have more flexibility in its set up than your average user will ever dream of needing.
It's also a handy fact that the THX mode, while not absolutely perfect (in that it looks a touch soft and tends to push orange a little hard for our tastes) is nonetheless a much more successful preset for watching HD movies than any of the factory-established presets you usually find on a TV.
The panel inside the P46GT30 is one of Panasonic's new NeoPlasma affairs, meaning that it benefits from that panel's pretty much wholesale improvement to everything from colour and contrast to brightness, power efficiency and response/decay time - the latter point being crucial to keeping dreaded crosstalk ghosting noise out of 3D pictures.
In fact, it's the P46GT30's freedom from crosstalk that remains to some extent its single strongest suit versus all the other 3D TVs that have come our way in the course of 2011. There really is hardly any of the double ghosting to be seen anywhere, not even when watching Sky's side-by-side 3D broadcasts.
We can't go so far as to call the P46GT30 'crosstalk free', as there are discernible signs of it every now and then. It's still visible during Tangled's always-revealing lantern sequence, for instance. But 'discernible' and 'visible' are a million miles from the levels of sometimes quite egregious crosstalk noted on many rival TVs, and for 95 per cent of the time it's so subtle when it does appear on the P46GT30 that you really have to be looking for it to become distracted by it.
The only extra point to add here is that we strongly recommend turning off Panasonic's Intelligent Frame Creation system while watching 3D, as leaving it on appears to slightly increase crosstalk.
The P46GT30's 3D performance is also done no harm by the extremely deep and believable black levels the set achieves, which immediately creates a more 'film-like' environment for the 3D pictures to work within.
Thanks to the set’s plasma technology, there's none of the backlight inconsistency you sometimes get with edge-LED TVs. This kind of backlight ramps up brightness levels to compensate for the dimming effect of active shutter glasses. There's even a fair degree of shadow detail visible in dark areas during 3D viewing, proving the worth of the improvements Panasonic has wrought to its plasma technology since its 2010 models.