In this article, we will learn the difference between screen tearing and ghosting. But I think before we do that, we should look at what each of these terms even means. Why it happens and how we can fix it. Because knowing what is happening at the fundamental level is how we can really fix things. Right? So in short, we are applying the first principle method here!
So are you ready to learn all there is to know about screen tearing and ghosting? Great! Then let’s get started!
Screen Tearing & Ghosting
What is Ghosting?
So let us start with Ghosting. What is it? Ghosting is a phenomenon in display screens. It happens when a part of the screen is not updated in time, or the color of the part is not consistent with the rest of the screen.
Because of this, a fast-moving object will leave a trail of its previous position on the display. So in other words, you can say that it happens when a single image is displayed for a long time. Sounds good?
Why Ghosting occurs?
But why does ghosting even happen? Well, there are many reasons for ghosting, such as the refresh rate of the screen is too low, the quality of the screen is bad, the angle of the screen is too large, the color of the screen is not consistent with the color of the back light.
So in general, it happens whenever a device is unable to render a fast-moving image properly.
But the most common cause of Ghosting is due to the wrong choice of display parameters, such as the refresh rate is too high, or the response time is too long.
How to fix ghosting?
So how can we fix it? To answer that, we need to first know this – Display ghosting is caused by the human eye’s persistence of vision, and the longer the display time, the more likely the ghosting will occur.
So in other words, if we look at something for a long time, we tend to retain its shape and size in our eyes as an imprint. So the easy way out of this is to change the things we see at a rapid pace!
The ghosting can be reduced by increasing the refresh rate of the display, or by reducing the brightness of the screen.
What Is A Screen Refresh Rate?
Wait, we talked about screen refresh rate in the previous paragraph. But what does that even mean?
The screen refresh rate is the number of times in one second that a display screen can completely redraw the image. The screen refresh rate is measured in Hertz (Hz). So higher the screen refresh rate, the more smoothly animations and movements appear. And as we read earlier, this also means we will not see ghosting anymore!
That kind of makes sense then right? But then comes my next question.
What should be the minimum screen refresh rate for smooth output?
So I went around looking for a decent value at which I should set my screen’s refresh rate. And guess what? The recommended screen refresh rate for smooth output is 60Hz. So this begs the next question for me.
What is the screen refresh rate of an LED TV?
The refresh rate of an LED TV is usually 120Hz. So this is what I found after looking at many latest LED TV specifications!
Is screen refresh rate of 120Hz good?
So then which refresh rate is really good for me? Should I set it at 60 Hz or 120Hz? Any guess?
Now if you said 120Hz, then you are right! But why? Read on to know the reason behind it!
At 120Hz, The frames are drawn at 120 frames per second. This is a huge improvement from 60Hz where only 60 frames are drawn per second. So a screen refresh rate of 120Hz is really good, as it can make the screen look very smooth and it is not easy to see the screen is flickering.
Okay then! 120Hz it is!
But here is the thing. As I continued to browse around the topic of refresh rate, I came across this other phenomenon called screen tearing! What even is this now?!
What is screen tearing?
As I looked around to find what it is, I learnt this:
Screen tearing is a graphical artifact in video games and computer graphics. It occurs when the frame rate of a video display does not match the rate of display updates from the computer graphics card.
Alright, very well! So now I have two things to worry about when displaying things on a screen. And here comes my next question – ladies and gentlemen!
What is the difference between screen tearing & ghosting?
Screen tearing is a phenomenon that occurs when the monitor is not in sync with the graphics card. Hmm…so it is not a problem with the display, but a problem with the way the graphics card is outputting the image.
But on the other hand, ghosting is a problem with the display itself. So they are indeed two different problems. But of course, the difference is very subtle from an end user’s point of view! Right?
How to fix screen tearing & ghosting?
So the bottom line is, both screen tearing and ghosting happens due to bad refresh rate of the display. But this refresh rate goes bad at both the display frame buffer side as well as the GPU side. So by fixing this refresh rate, things must get back to normal!
Aha! What an elegant solution to each of these problems!
But where do we see ghosting & screen sharing?
Well the answer is, pretty much on every mobile phone! Be it a gaming smartphone like Asus ROG Phone 3 or your granny’s old feature phone. This is a problem that can happen on any device with a screen and capable of drawing graphics on it!