Screem Ghosting Effect: Definition
The term ghosting covers various functions and mechanisms from a wide range of subject areas. In this article we will deal with the ghosting of monitors or screens, televisions, and keyboards. For screens or monitors ghosting refers to the display of a so-called ghost image, hence the name ghosting.
A weakly displayed and usually much less luminous copy of a displayed image, the main image, is called a ghost image. The underlying effect, i.e. the display of this ghost image, is called ghosting.
In most cases, this effect only occurs in TV sets when they receive analogue signals. This excludes transmission via satellite. In the case of analogue cable or terrestrial TV transmission, however, the image error may very well occure. The reason is that the signal is reflected by any object on its way from the transmitter to the receiver.
The signal after reflection lands at the receiver. At the same time, however, the receiver also receives the signal directly. However, the reflected signal has a longer path behind it and therefore arrives with a time delay. This can lead to the fact that this image, attenuated, is also displayed. You can go a little deeper into this topic and google it or read more about it on Wikipedia.
The new digital transmission technologies DVB-C, DVB-S and DVB-T are, however, conditionally spared from the picture error usually if there are no other connectivity issues. It is simply not possible that ghosting occurs through this transmission technology.
Test your TV screen or computer monitor for ghosting
If you want to test your TV screen or mointor for ghosting, you can do so with the following test. The test takes place approximately in the middle of the video. In the video description you can also download the test if you don’t have access to YouTube on your TV or don’t have a Smart TV.
When playing the video, you should always be able to see all objects sharply and clearly, especially they should not be offset from each other. If this is not the case, your monitor will suffer from the picture error, because it still shows the previous picture partially.
Ghosting on 3D Monitors
Another form of image error is also found in the 3D display via a corresponding monitor or 3D television. If the channels are poorly separated, it is possible that a picture, or even only a partial picture of one channel is displayed in the other.
What can you do against ghosting?
Unfortunately, there are not many ways to counteract the image error. Most of the time you are powerless, but in a few cases there are a few solutions that you can try: For example, you can set the energy saving settings to a minimum or disable them completely. This can cause the liquid crystals to update more quickly.
Heat also helps, which is why the picture error may only occur at (very) low temperatures. However, this is rare, and a warm panel often has other disadvantages such as banding. Also, a monitor is rarely below 10° cold, so you could really feel some effects here. That leaves only the option to return the screen to the manufacturer if you still have warranty, even if that is really annoying. Depending on the dealer, this is possible without any problems, or not.
As a preventive measure, you can do something about the picture error, simply by testing the corresponding TV or monitor. Once you have decided on a television, it is best to go to the nearest specialist shop and look at the test pictures.
With a little less effort, you may also achieve the desired result: Simply search for the corresponding model using Google or another search engine and find out whether the picture error or other picture errors are to be expected.
What is Anti-Ghosting in Keyboards?
Unfortunately, even the advertising term “Anti-Ghosting” does not protect you 100% from the ghosting effect. Unfortunately, Anti-Ghosting is used in marketing in a very misleading way. As so often in life. Anti-Ghosting simply means that the tolerance of simultaneously pressed keys is set very high. So usually the number of keys to be pressed simultaneously is only a certain subset of the existing keys on your keyboard. What does this mean in practice? For example, an anti-ghosting keyboard usually protects the WASD block or the arrow keys (direction keys) from ghosting. This method is cheaper and easier to handle for the manufacturers. At first glance, you might think that this method works perfectly. But there are some problems with that.
There is also often the advertising promise that the keyboard protects up to a certain number of simultaneous key commands. Unfortunately, this is no more than an empty promise.
But why are entries lost?
The problem is usually the result of one or more causes. There are three common scenarios that can occur individually or in combination: The gaming keyboard cannot evaluate the pressed key combination (ghosting), the keyboard drivers or the used software do not support simultaneous pressing of several keys, or the transport protocol (USB vs PS2) is limited in its transmission of simultaneous key commands.
And why can the keyboard not register some combinations?
How are some key combinations not accepted? The answer is a little technical. We will try to explain it as simple as possible.
As mentioned above, a keyboard works in a “matrix system”. This matrix consists of rows and columns. The contacts of the individual keys are not evaluated separately, but are located on the matrix. See the matrix figure below.
Why do the manufacturers do this? That is quite simple. It saves a lot of money as they can save a lot of material from less needed wires in their keyboards. Your software driver now recognizes which button was triggered by connecting the row and column.
As you can probably quickly see, these marketing terms like n-key-rollover anti-ghosting, don’t always deliver what they promise you. Especially for gamers who don’t use the standard WASD allocation, the problems described above can quickly occur. And this although the keyboard promises Anti-Ghosting. Therefore you should pay attention to good quality when buying. Unless Anti-Ghosting is not that important to you. If you want it to work at least decently, you should go for a more expensive but higher quality mechanical keyboard such as the Logitech G910 Orion. There you will surely get the maximum Anti-Ghosting that is technically possible.
Short: What is Anti-Ghosting?
To understand what Anti-Ghosting is, you need to know what Ghosting is.
- Ghosting refers to a problem that many keyboards have: If several adjacent keys are pressed simultaneously, key combinations no longer work properly. The reason for this is the way the keyboard is ghosting.
- Especially in gaming, however, it happens quite often in the heat of the moment that the player inadvertently presses several keys at once. The consequence is that some keys then react sluggishly or report that they have not been pressed at all – this is then a “ghost”.
- This is why gaming keyboards have anti-ghosting. A different switching of the keys should avoid the problem of ghosting.
- However, in most keyboards, anti-ghosting is limited to certain areas of the keyboard. Since gaming mainly uses the WASD block and the direction keys for control, usually only those areas are optimized for error-free operation.
This video gives a great overview over anti-ghosting keyboards for gamers.