No smooth colour transition on Panasonic Plasma

[admin_exported]

Hi,

I own a Panasonic TH37PA60E Plasma television with the following kit:
- a Denon 1930 DVD player connected through a Profigold HDMI cable
- a Samsung DCB9401R set op box connected through a Profigold Scart cable
- a Yamaha RXV557 home cinema amplifier through profigold component cable

The problem is as follows: the TV seems to struggle with dark colour gradients especially with DVD's, showing not a smooth gradient, but a rather abrupt. I don't know what the proper wording is for this. But for instance in underwater scenes in movies where the water is greenish and the colour should go from dark to light green, you can see this done in steps rather than a smooth transition. Is this a known problem, what causes it and what is the solution?

What I already did: change DVD player (Yamaha DVD510), change connection types (Scart RGB). Could it be my Home Cinema speakers that aren't properly shielded? Perhaps other interference?

Thanks!

 

[Clare Newsome]

Hi there,

Standby for a detailed answer from deputy editor, Andy Kerr - emailed from the depths of our testing rooms....

It's called 'banding'. Some also call it solarisation. All flatscreens are susceptible to it. It's not caused by speakers or interference: it's intrinsic to the software and the display. Hardest to render are medium-dark to dark scenes: most flatscreens cannot display the information correctly, and instead display a mush of colour bands, odd contours, and sometimes just the wrong colour entirely. Plasma and LCD makers are getting better at improving this issue every year, but it remains a weakness for many.

HD and DVD sources will look better than cable or satellite simply because there is more data in the picture in most cases, especially with HD. When image processors have more data to work with, they make fewer mistakes. Incidentally, the reason old-school, interlaced, direct-view CRT TVs look better with standard-definition sources is that the interlacing process, and, typically, the smaller size of the screen, are actually hiding a lot of imperfections. With today's much larger screens you're simply revealing how bad standard-definition sources are.

A newer plasma or LCD will do better, especially when fed with HD, but the only real solution to the issue is the advent of a system called 'Deep Color' (sic). A part of the HDMI 1.3 specification, it potentially solves the problem by allowing for far greater colour variation on flatpanel TVs, thereby ensuring smoother colour variations and less (or possibly even no) visible banding.

Selected highlights (copied straight from www.hdmi.org) include:

Allows HDTVs and other displays go from millions of colors to billions of colors
Eliminates on-screen color banding, for smooth tonal transitions and subtle gradations between colors
Enables increased contrast ratio
Can represent many times more shades between any two colors, and many times more shades of gray between black and white. At 10-bit color depth, four times more shades would be the minimum, and the typical improvement would be eight times or more.

However, while Deep Color compatible displays are starting to come on to the market, there's currently no software, or broadcast content, to take advantage of its capabilities. Watch this space.