To test a monitor for defects, use online tools like EIZO Monitor Test or black-screen.cc to check for dead pixels, colour accuracy, and screen uniformity by displaying solid colours, gradients, and patterns in full screen. For hardware, run the monitor’s built-in self-test (BIST) by holding ‘D’ while turning it on.

Key Testing Methods

• Dead/Stuck Pixel Test: Display solid black, white, red, green, and blue screens to identify spots that do not change colour.
• Colour & Brightness Uniformity: View grey and white screens to check if brightness or colour is uneven across the panel.
• Ghosting/Response Time: Move a white box across a black background to see if a “ghost” image trails behind, indicating slow response.
• Sharpness & Focus: Display text or a chequerboard pattern to check if the image is crisp or blurry.

Steps to Take Before Testing

• Warm up: Let the monitor run for at least 30 minutes to stabilize.
• Clean: Wipe the screen to distinguish dirt from dead pixels.
• Disable Settings: Turn off automatic features like Night Mode, True Tone, or auto-brightness for accurate colour assessment.
• Common Issues to Look For
• Dead Pixels: Black, white, or coloured dots that never change.
• Backlight Bleed: Light leaking from edges or corners on black backgrounds.
• Flickering: Unstable brightness or image distortion