The L42ET5's picture quality promises to be more interesting than most thanks to the set's marriage of core LG passive 3D technology with Panasonic's own processing and presentation systems. Hopefully it will deliver the best of both worlds rather than ending up feeling like a marriage of inconvenience.
Starting with those all-important passive 3D images, the L42ET5 happily provides another mostly very positive outing for the technology. Watching a variety of 3D content, from the animated likes of the excellent Tangled to the video delights of the vastly over-rated Avatar, the L42ET5 delivers a consistently natural, unfatiguing, reasonably deep 3D picture that's largely free of crosstalk and completely free of active 3D's flickering issues, even if you watch it in broad daylight.
The passive glasses knock less brightness and colour out of 3D images than active shutter ones do too, reinforcing the sense of passive 3D's advantage if you generally find yourself watching TV in bright room conditions. The extra dynamism is particularly helpful when rendering dark scenes, especially when compared with how 3D plasmas operate.
It's also nice, of course, that a four-strong family can all watch 3D without you having to fork out extra cash for more glasses.
Video enthusiasts able to dim the lights for serious 3D viewing, though, should be aware that the L42ET5's passive 3D pictures do not look as sharp or 'HD' as those of even Panasonic's 2011 active 3D TVs. Anyone thinking of mounting their new TV up high on a wall should note as well that crosstalk levels balloon from practically none to dire the moment your vertical viewing angle gets beyond around 13 degrees.
Also potentially disturbing is the appearance over some content - mostly expanses of light colour or the edges of bright objects - of horizontal line structure, caused by the polarising filter applied to the screen's front.
Before anyone gets too discombobulated about this, though, the problem really isn't very aggressive, so long as you're watching from a sensible viewing distance. The relatively demure size of the screen helps hide the negative impact of the filter too, making it much less noticeable than it tends to be on larger passive 3D screens.
Balancing up all the pros and cons of the L42ET5's 3D performance, the good stuff definitely wins out so long as you're not the sort of AV enthusiast who expects your 3D performance to look quite as detailed and crisp as your 2D HD Blu-rays.
Talking of 2D HD, this too looks rather good on the L42ET5. Whether it's a Freeview HD feed from the built-in tuner, a Sky HD feed or a Blu-ray, the set does a very respectable job for its money of reproducing both the detailing and the colour information in the images aggressively yet accurately.
It helps in this respect that the screen is only very slightly troubled by the sort of motion blurring that's common with most brands of LCD TV. And what little blur there is can be reduced by judicious use of Panasonic's Intelligent Frame Creation processing. By judicious, we mean you should take care not to use it on its highest power setting, as while this completely eradicates blur and, especially, judder, it also causes a few distracting side effects with fast-moving footage, and generally makes film footage look more like video footage.
It's gratifying to see, too, that dark scenes don't suffer with the sort of backlight consistency issues noted with some of LG's passive 3D TVs - and many other edge LED TVs besides. In fact, so uniform do the dark parts of dark scenes look on the L42ET5 - so long as you avoid the set's Dynamic preset, at any rate - that it's easy to forget that the TV is using edge LED technology.
What's even better about this is that the TV still delivers a fair approximation of a true black colour. Sure, there's a very slight grey mist over the very darkest parts of pictures that you wouldn't get with a good plasma or direct LED TV. But this certainly doesn't prevent the picture from still looking dynamic during dark sequences, and nor is it bad enough to 'hide' the sort of shadow details that give dark scenes a sense of 'space'.
If you were being really picky, you might say that the L42ET5's colours sometimes lack a little finesse in HD mode, leaving some areas looking slightly plasticky. But overall there's not much to complain about considering the set resides fairly low down Panasonic's new range.
The L42ET5's relative affordability does become more troublingly apparent, though, when you're watching standard definition. For this tends to look rather soft compared with the upscaled images you might expect to see from some other LCD TVs.
This might have been easier to live with if the soft tone had been used to hide noise in standard def sources, but actually the L42ET5 slightly exaggerates source noise rather than 'smoothing it away'.
Even the screen's colour response takes a hit with standard definition, with the range of tones on display looking somehow less extreme than with HD sources. Odd - but a phenomenon we're familiar with from some LG TVs, funnily enough.
There's one more area where the L42ET5 suffers from its LG roots too, and that's input lag. Too long a delay between a source signal arriving at a TV's inputs and the picture appearing on the screen clearly has the potential to harm a keen gamer's performance, and the 75+ms input lag measured at times from the L42ET5 clearly constitutes a potentially problematic level of delay. Similar figures were routinely recorded from LG TVs last year, whereas Panasonic's own-built LCD TVs never went higher than a much more manageable 40ms.