LG 47LK520 LCD HDTV Review
$899.00- Sections:
- Black Level
- Peak Brightness
- Contrast
- Tunnel Contrast
- White Falloff
- Uniformity
- Greyscale Gamma
Black Level
Not a bad black level for an LCD screen, it's just that the 47LK520 is playing in a competitive crowd, with the Samsung leading the pack by quite a margin. More on how we test black level.
Peak Brightness
The peak brightness for the LG 47LK520 is strong, but again, similar models are a little bit better. The Samsung has exchanged brightness for a low black level and the advantage is in the contrast ratio. More on how we test peak brightness.
Contrast
Contrast ratio lets you know the range of values a television can use to display images. A higher contrast ratio means more values, which means more detail and ultimately a more realistic looking picture.
Anything over 1000:1 is good. The 47LK520 barely hits this mark, so there are no worries about its black/white competency. But in terms of quality, you can get better from the other televisions we've shown here. More on how we test contrast.
Tunnel Contrast
We are looking for a flat line in this graph, which would indicate that the black level stays consistent with changes in areas displaying pure black. The small peaks in this graph are small enough to be ignored, so we say the LG 47LK520 has a very consistent black level. More on how we test tunnel contrast.
White Falloff
The horizontal line in the chart below says that the peak brightness, displayed in areas of pure white, does not change depending on the size of these areas. The LG 47LK520 displays white at a consistent luminance, regardless of how much white is on the screen. More on how we test white falloff.
Uniformity
We look at all-white and all-black screens to check for inconsistencies in the picture. For instance, on an all-black screen of the 47LK520, we could see some of the backlighting shining through the darkness making cloudy patches of grey at the edges of an otherwise black screen. These patches sometimes encroached on the middle of the screen, but were even and not splotchy, so they were not too distracting.
An all-white screen looked great, with only a very slight dimming of corners, and only if you are looking with a reviewer's cynically critical eye. More on how we test white falloff.
Greyscale Gamma
This is one of the best greyscale graphs we have seen in a while. We look for a straight, smooth line with a slope between 2.1 and 2.2. The line in the chart below is scarily close to this ideal, with a straight line sloping at 2.28, that's as smooth as rocks out of a tumbler.
These points of quality mean that the 47LK520 moves from black to white in evenly incremental steps, all of which are different than any other. Why is that a good thing and why the hell do I care? you may ask, possibly using more expletives.
It is the transition between light and dark that creates the illusion of three dimensions on a two dimensional surface. Think of a sphere, and try to describe its curvature with only three values: black, middle grey, and white. You could make a circle and shade it in the right areas, but it would not look very real. If you added several more values of grey, you could make a more realistic sphere, and more values would make for more realism. Ideally, you would use as many values possible to describe this sphere.
This wonderfully formed greyscale graph shows us that, within the range of possible dark and light (the contrast ratio), the 47LK520 isn't skipping values, thereby using most of the values in its range. Essentially, the 47LK520 is able to display the most amount of values it possible, given its contrast ratio, which was reasonably strong as well. More on how we test greyscale gamma.