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Picture Processing

The next thorny issue for this feature was how to structure it in the most helpful way. After a couple of false starts, the approach that seemed to work best was to work through the key picture elements one at a time, giving some basic tips for people not wanting to buy any calibration discs, and then getting into how to use the discs instead.

So let's get down to business. Starting, you might be surprised to hear, with the ever-controversial area of video processing.

The very first thing I do when I get any new TV for testing is trawl through its onscreen menus looking for any picture processing options I can find - noise reduction, edge enhancement, 100Hz, 200Hz, frame interpolation, colour boosters, black level boosters etc etc. And then I turn absolutely every last one of them off, if the menus allow me to. Why? Partly because turning everything off helps me assess the quality of the ‘naked' plasma or LCD panel at the TV's heart. But also because experience suggests that manufacturers just love to show off their processing wares as aggressively as possible, with little thought of whether it's actually any good for the overall picture quality.

Turn all this off to start with

With noise reduction systems, for instance, you generally find that they soften pictures up quite alarmingly. Or Edge Enhancement systems make things look too gritty and rough. Or black level boosters push out too much subtle shadow detail. Or motion processing causes nasty side effects that are arguably more distracting than the motion blur/judder issues they were designed to circumvent. And so the list goes on.

I'm not saying here that all picture processing systems are a waste of time. Far from it; some can have a dramatically beneficial impact on pictures, as you'd expect. But I definitely believe that video processing has to be used with care. And the best way to calculate their worth is to add processing elements to a ‘naked' picture one at a time, starting with the most gentle settings each option has available and building them up until their benefits start to turn into problems.
Picture processing tools hide in many different menus

Of all the picture processing systems I've come across on TVs, it's the ones purporting to reduce noise and sharpen pictures that have to be treated with the most care.

If you want to give your different processing systems a real work out, the HQV disc really comes in handy. The main focus of its test signals and procedures is to figure out just what sort of impact your TV's video processing is having on the picture - especially when it comes to noise reduction and motion boosters.

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