Blog
Filming an LED poster: flicker, bands and moire
Many LED posters end up on camera: in a store video, on social media, at an event. A screen that looks steady to the eye can show bands or moire in a phone video. This article explains the causes and a simple test to run before you commit to a position or a pitch.
- 3840 Hz or higher
- Phone test
- Moire
Why a camera sees what the eye does not
A camera takes pictures at a fixed shutter speed. If the shutter and the screen refresh do not match, dark bands can run across the picture. The effect depends on the camera, the settings and the screen. The refresh rate of our posters is 3840 Hz or higher, which reduces visible flicker on camera, but the result still depends on the phone.
Moire
Moire is the wavy pattern that appears when a camera sees two fine grids overlapping: the sensor and the grid of LEDs. It is stronger on a fine pitch seen from close, and it changes with the distance and the angle. Moving the camera a little or changing the zoom changes it.
A simple test
- Load a plain color and a fine-line test pattern on the poster. 2. Film it with the phone your audience uses, at the distance and angle they will use. 3. Change the shutter speed or the exposure if your camera allows it, and film again. 4. Watch the video on a large screen, not only on the phone. Write down the settings that worked and share them with your team.
Content that helps
Avoid very thin lines and very fine patterns, which provoke moire. Use a smooth gradient or a photo for the background, and keep text large. The content creation checklist has more steps.
Brief the camera operator
Give the operator the pitch, the viewing distance and the content files before the shoot, and ask for a test clip at the real position the day before. Keep the camera at a steady distance during a take, because moving closer or further changes the pattern. If the poster is the main subject of the shot, do the test with that exact artwork.
Choosing the pitch for a shoot
If the poster is a backdrop for video, a viewer at 2 m is served by P1.86 or P2 for the eye, but the camera is a second viewer. A test with your camera at the shooting distance decides. See the pixel pitch guide.
Questions and answers
What refresh rate do your posters have?
3840 Hz or higher.
Does a high refresh rate remove all bands?
It reduces visible flicker on camera, but the result depends on the phone and the shutter speed.
What causes moire?
Two fine grids overlapping: the camera's sensor and the LED grid. Change the distance, the angle or the zoom.
Which phone should I test with?
The phone your audience uses; results differ between phones.
Does a finer pitch make moire worse?
It can be stronger on a fine pitch seen from close, so test at your real distance.
Can I film with a professional camera?
Yes, and test it the same way: plain color, fine lines, change the shutter speed.
Does the content change how it looks on camera?
Yes. Thin lines provoke moire, smooth gradients and photos do not.
What should the test pattern contain?
A plain color and fine lines, as in step 1 of the test.
Request a quote
Request a quote and tell us the type, the pixel pitch, the quantity, the destination country and your control system (NovaStar with Mean Well PSU by default; Huidu or Colorlight as a lower-cost option). Price, MOQ and lead time are quoted per order. Samples are available.