With the requirement for high-definition display, P2.976 outdoor rental LED display is used more and more. Because the outdoor rental display of this point is close to the small-pitch LED display, it is used on stage rental. degree is absolutely no problem.

However, stage performances often need to shoot a lot of pictures or videos, even live broadcasts, and shooting such electronic products is most prone to “water ripples”. For photographers who often shoot, they should often encounter. For this problem It’s also a headache. So, do we have a way to eliminate “water ripples”? Let’s find out.

“Water ripple” is “Moire”

The “water ripple” encountered by the P2.976 outdoor rental LED display is also called “moiré pattern” or “moiré pattern”. There are many names like this transliterated word, especially in the name of the person. Inside, taking “Trump” as an example, we can translate it into Trump, Trump, Trump, etc. So we don’t need to be too entangled here.

Back to the topic, when we use a digital camera to shoot the scene of the P2.976 outdoor rental LED display, if there is a dense texture, there are often streaks like water waves, which are moire patterns.

The image on the left shows distinct water ripples

In fact, not only outdoor rental series products will appear, but all LED display products will have them. Simple understanding, moiré is the performance of the beat principle. Mathematically, two equal-amplitude sine waves with similar frequencies overlap, and the amplitude of the resulting signal varies by the difference between the two frequencies.

Because it is somewhat similar to the “scan line phenomenon”, some people will confuse the two. In fact, the difference between the two is quite obvious, because the scan line is a horizontal black stripe line, mainly because the refresh rate of the display is too low, and it is captured by the camera. The water ripples are due to the fluctuation of the spatial frequency, and the irregular arched shape spreads.

The production process of “water ripples”

When there are two stripes with slightly different spatial frequencies, since the black lines at the left end are at the same position and have different intervals, the lines cannot be gradually overlapped toward the right.

The two stripes overlap and the black line on the left overlaps, so the white line is visible. Then, the right side is offset little by little, with the white line towards the black line, and the result of the overlap becomes black. There are variations of white lines and all black, which form a moiré pattern.

The pixel distribution density of the full-color display panel is just in the interval that the CCD can recognize, and the digital camera must interpret the result that can be recognized. Visually it is a periodic ripple.

After adjusting the angle, the ripples become less pronounced

Knowing the reasons for the formation of “water ripples”, do we eliminate them? The answer is yes! We can use the following methods to eliminate the moiré of the LED display.

  • Change the angle of the camera. Because the angle of the camera shooting the object will produce ripples, we can try to change the angle of the camera slightly, for example, when shooting at a positive 90°, we can try to rotate 90° after shooting, which is helpful to eliminate or change the existing ripples.
  • Change the camera position. By slightly moving left and right or up and down, to change the relationship of the shooting angle, it is also possible to reduce the moiré ripple.
  • Post-processing with software. We can eliminate the moiré in the final image by using software in the later stage, the picture can use PS software, and the video we can use PR and AE software
  • Change focus. Sharp focus and high detail can cause moiré, and slightly changing focus and different lenses, with varying sharpness, can also help remove moiré.

Install the pre-lens filter in front of the CCD to make the exposure conditions meet the spatial frequency, thoroughly filter the high spatial frequency part of the image, and reduce the chance of ripples on the LED display, but this method is not recommended, after all, it will also Decrease the clarity of the image

The above is about the elimination method of “water ripples” that appear on the LED display screen when shooting. If you have other content you want to know, please contact us through the information above.

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