What really matters in the television to get a good picture

Jens Kretschmer can already look back on 25 years of experience as a TV master technician. In his business in Ahrensbk in Schleswig-Holstein, he advises the local customers. With TECHBOOK, Kretschmer shares his knowledge and reveals the role of resolution, price and technical details in the purchase and why many of the manufacturers’ specifications are to be treated with caution.

With these 5 tips you get everything out of your TV


The resolution is probably the best known of all factors. Meanwhile, most new TV sets are offered with a so-called UHD or 4K resolution. These are around four times as high as the once-standard Full HD.

In theory, a higher resolution means a sharper picture. But that always depends on the program. There are still only a few content in UHD and 4K available. If anything, these are available on Netflix or Blu-Rays and only occasionally on special TV channels or individual broadcasts. Nevertheless, a new device should have the higher resolution. According to Jens Kretschmer, this is the future: “Everything is clear from the norm. UHD makes perfect sense when you buy it. “

screen size

This describes how big the screen is and is given in inches or centimeters. 1 inch corresponds to 2.54 centimeters. A 50-inch TV has a screen diagonal of 127 centimeters. How big the TV should be depends not only on personal taste. Rather, buyers should measure in advance the seat distance to the device in their own home. Based on the distance you can determine the size of the TV should have, so you have the best possible viewing experience. How to determine the optimal seat distance, you can find out here.

Refresh rate (Hertz number)

The Hertz number (Hz number) indicates how fluently movements are represented. This may be especially important in sports broadcasts and fast motion in movies. If the value is too low, it will lead to unsightly blurring effects. Basically, the higher, the better. At least 400 Hz should therefore bring better devices. But Kretschmer warns not to rely on a number here. The actual image processing also depends on other factors, such as the installed operating system, the processor and the remaining built-in technology. The expert compares the Hertz number with the horsepower in a car. Just because a vehicle has a lot of horsepower does not mean that it also accelerates well. How much power the car brings to the road ultimately depends on the chassis and the weight of the car.


Manufacturers of televisions are launching several series of televisions to serve different price segments. At first glance, the differences between a cheap and an expensive device are often not clear. Does the price therefore not play a big role? “Yes!” Says television technician Kretschmer. “A good UHD device with a screen diagonal of 50 inches should cost at least 1000 euros.” Then the customer can also count on high-quality components.

HDR (High Dynamic Range)

HDR is intended to deliver higher-contrast and more vivid images. The higher image contrast results from an increase in the brightness span width and achieves a greater depth effect. The picture looks more plastic, because HDR recognizes more brightness nuances and better shadows objects. Whether you actually get an HDR image depends on several factors.

First, the entire transmission path HDR support, so the screen, the player, the connection cable and the disk. If the path is interrupted even in one place, the final image will not be broadcast in HDR. In addition, there are not many TV sets that can really portray HDR, even if they adorn themselves with said logo. The logo only means that the device can read the signals. The transmission usually fails because the devices do not reach the necessary brightness span. Again, the price is a good indicator. More expensive devices are usually able to display HDR as desired.

The program is important

A good picture is not only on the TV. Even the best TV, always needs the appropriate program. While Blu-Rays and streaming services are already delivering very good signals here, the classic TV program, in particular, is lagging behind. Not only does the station play a role here. Even within a transmitter, different programs can be produced in different qualities. As a result, in the best case, you would also have to change your TV settings for each broadcast. Since this is annoying in everyday life, the expert recommends to be sparing with the numerous setting options and alleged image enhancers. Please read our article about the perfect TV settings.