Panasonic TX-40AS640 – Picture Quality
The 40AS640’s pictures might not be perfect, but they’re still very good at this price.
The star of the show is the 40AS640’s contrast compared to that of most similarly priced rivals. So long as you keep its backlight setting reined in, especially when watching it in a dark room, this Panasonic can give you a far more successful combination of reasonably deep black levels and good backlight uniformity than you’ve any right to expect for so little money.
What’s more, since the set isn’t having to work nearly as hard to produce a decent black colour as the IPS TVs in Panasonic’s current range, you can boost contrast marginally by using the dynamic contrast feature without it causing as many distracting brightness ‘leaps’ or inconsistencies.
The decent native black level of the 40AS640 additionally means that it’s better at retaining shadow details than the majority of its similarly affordable rivals.
Turning to other aspects of the 40AS640’s pictures, while its colours aren’t the most vibrant we’ve seen this year, they’re still very satisfying – with HD content, at least. Hues are natural, balanced and subtle.
HD pictures also look clean and pure, and this feeling doesn’t break down badly at all when there’s a lot of motion in the frame. This is another key area where Panasonic’s mid-range bargain earns major points over the majority of its similarly affordable competition, which tend to soften and blur badly during camera pans or action-packed scenes.
As we said earlier, though, while far above average for a £400 feature-rich 40-inch TV, the 40AS640’s pictures aren’t perfect. We’ve already noted that colours aren’t the most vibrant around, but it’s worth adding that part of this is down to the fact that, by the time you’ve optimised the backlight setting to achieve the best black-level response, you’re left with pictures that really aren’t very bright.
Surprisingly, given the generally good quality of the 40AS640’s processing we weren’t blown away by the quality of the 40AS640’s standard-definition playback either, which leaves pictures looking a bit soft and simplistically coloured.
Also unfortunate is the way the screen turns off its backlight completely during fade-to-blacks. This results in you becoming distractingly aware of the mechanics of the lights shutting off and suddenly sparking on again once some light returns to the source image.
Finally, while the 40AS640’s HD pictures look polished and clean, they’re not the crispest, sharpest HD images around, even if you’ve got all the softening noise-reduction features turned off.
How we test televisions
We test every TV we review thoroughly over an extended period of time. We use industry standard tests to compare features properly. We’ll always tell you what we find. We never, ever, accept money to review a product.