How do I best set up my LCD television?
By Simon Blohm
The image quality on modern LCD televisions can be improved considerably using the correct settings in the TV’s On-Screen Menu. The factory settings are often not perfect, but are adjusted for presentation in the store of a retailer and display an exaggeratedly colourful image in order to impress potential buyers.
An optimally adjusted television should reproduce image data in a form that is true to the original. This means that no colour gradients should merge into each other, contours should be clearly visible and the image should not be too bright or too dark overall. The television should also be adjusted to the illumination within the room in which it is located. Very bright rooms require a brighter television picture and in dark rooms, the image should not be too bright since this is hard on the eyes in the long term.
Most televisions allow the values for brightness, contrast, RGB levels, sharpness, gamma and colour balance to be adjusted in order to optimise the image. Contrast denotes the difference between bright and dark areas in an image. If the contrast is too low, the image looks flat and colourless, but if the contrast is too high, the image displays silhouettes and is artificial looking. A good contrast value will support colours but will not make them too strong. The colours themselves are adjusted using the RGB levels. These determine to what proportion red, green and blue are visible in the television image. Ideally, they are present in equal strengths, but some televisions tent somewhat towards green – simply because the human eye recognises more green tones than red or blue tones.
Amazon: Reference DVD
The gamma value is also based on the uniqueness of the human eye; the eye does not perceive increases in brightness in a linear manner. Gamma adjusts the brightness behaviour of the television such that perceived brightness increases more steeply in dark areas and less steeply in bright areas. This means that the middle area of brightness is represented more strongly than the extremely bright or the dark. The gamma value therefore indicates from when colours are displayed more brightly or more darkly than they actually are. Ideally, the gamma value should be 2.2, since this value makes the overall image look somewhat "crisper".
For LCD televisions, brightness (and therefore gamma) and contrast are of particular importance. Since LCD televisions function using a backlight, black is never 100 percent dark. For this reason, many users tend to set their televisions too dark. On the other hand, for very bright rooms, the user often selects too high a basic brightness for the television, which also fails to deliver an ideal result. A dilemma in which visual judgement unfortunately fails.
First resort on the Internet for test images: Burosch Audio-Video technology. The AVEC test image can be seen here (Photo: Burosch)
One way to adjust colour settings relatively precisely is to use test images. These are often to be found on DVDs which are included with the relevant HiFi journals. Some movie DVDs offer test images and even test sounds as part of their bonus material. THX certified DVDs generally come with such extras. Naturally, reference DVD can also be purchased.
However, relevant DVDs can also be procured as free downloads on the Internet. In the age of DSL and flat rates, this is generally not a hindrance, provided that your PC equipment includes a DVD burner. The Internet site Burosch Audio-Video technology can be named as a first resort in such situations, being one of the most recognised test image suppliers in Germany.
Test images function according to a simple principle: if the television is not set up properly, the test image will not be displayed properly. Although this is the case with all images and films, test images contain special scales and colour gradients which allow you to recognise the incorrect settings and their type and extent.