Comparison Samsung UE-55RU7172 55 " vs Samsung UE-55RU7400 55 "

Dynamic Scene Index (DSI) provided by the TV screen.

DSI is a rather specific parameter that can be called "visible framerate". Its appearance is due to the fact that a high frame rate is highly desirable for dynamic scenes — it provides smooth images and good detail of moving objects. However, for technical reasons, it is not possible to achieve indicators above 200 Hz in most screens. In order to remedy the situation, manufacturers use special technologies that create the effect of increasing the frame rate.

Such technologies may have different names, but they have the same principle of operation — inserting additional frames between the "own" frames of the video being played. And the dynamic scene index describes the overall effectiveness of such technology used in a TV. For example, a DSI of 200 Hz means that the image quality on the screen approximates a frame rate of 200 Hz, although the actual frame rate is often as low as 50-60 Hz.

In the most advanced models, the dynamic scene index can be up to 3000 Hz, and options above 3000 Hz are considered to be TVs with a high dynamic scene index. However, it is worth noting that such specifications are more of an advertising ploy than a real advantage: in fact, the threshold for human perception is 400 – 500 Hz, a further increase in the DSI does not give a clearly visible improvement in the image.

TV support for one or another brightness / contrast enhancement technology.

Usually, in this case, software image processing is implied, in such a way as to improve brightness and/or contrast (if necessary). Specific processing methods may be different — in particular, in some cases we are actually talking about turning standard content into HDR (see above), and some manufacturers do not specify technical details at all. The effectiveness of different technologies can also be different, and besides, it is highly dependent on the specific content: in some cases, the improvement will be obvious, in others it may be almost imperceptible. Also note that this feature is not always useful, so in most models it is turned off.

The TV's support of one or the other colour enhancement technology.

Such technologies usually involve image processing in software to provide brighter and/or more accurate colours. Specific processing methods may be different, some manufacturers do not specify technical details at all, limiting themselves to advertising statements. The effect of using such technologies can also vary: in some cases it is clearly visible, in others it is almost absent, depending on the features of the picture. It is also worth saying that this feature, usually, needs to be turned on manually in the TV menu (accordingly, it can be turned off if desired).

About the interface itself, see above, and its different versions differ in maximum resolution and other features. Here are the options found in modern TVs:

— v 1.4. The oldest of the current versions, released in 2009. However, it supports 3D video, capable of working with resolutions up to 4096x2160 at 24 fps, and in Full HD resolution, the frame rate can reach 120 fps. In addition to the original v.1.4, there are also improved modifications — v.1.4a and v.1.4b; they are similar in terms of basic features, in both cases the improvements affected mainly work with 3D content.

– v 2.0. Significant update to HDMI introduced in 2013. In this version, the maximum frame rate in 4K has increased to 60 fps, and the audio bandwidth has increased to 32 channels and 4 separate streams simultaneously. Also from the innovations, we can mention support for the ultra-wide format 21:9. In the v.2.0a update HDR support was added to the interface capabilities, in v.2.0b this feature was improved and expanded.

— v 2.1. Despite the similarity in name to v.2.0, this version, released in 2017, was a very large-scale update. In particular, it added support for 8K and even 10K at speeds up to 120 fps, as well as even more expanded features for working with HDR. Under this version, its own cable was released — HDMI Ultra High Speed, all HDMI 2.1 features are available only when using cables of this standard, although basic functio...ns can be used with simpler cords.