Instructions: This test is designed to test for blooming in the local dimming capabilities of a display. Adjust shape size, color, density, brightness, and direction to maximally amplify local dimming artifacts on this specific display and its count of local dimming zones. Then run in full screen mode. The more backlight zones your display has, the less visible blooming artifacts generally are. Try these preconfigured tests:

• For 1000-zone MiniLED: Cyan 10px Squares
• For 1000-zone MiniLED: Yellow 40px Vertical Lines
• For 100-zone FALD: UFO Invasion

Pros & Cons of Local Dimming: Zone-based local dimming allows darker blacks on displays otherwise incapable of perfect blacks, such as LCDs. However, blooming (halos) can become visible at the boundaries of local dimming zones, which can become more visible when the background is black and the display has fewer local dimming zones.

What Displays Use Local Dimming? Most computer monitors and mobiles do not support local dimming. However, if your display is advertised as having "MiniLED", "FALD", "Local Dimming", "Dimming Zones" or similar terminology, your display uses local dimming.

Per-Pixel Local Dimming: Some displays such as OLEDs and direct-view MiniLED / MicroLED displays (with no LCD layer) are capable of full brightness pixels adjacent to full blacks, and will show no blooming.

NOTE: When testing with cameras or eyes, make sure to consider lens-related effects (e.g. fingerprints on lens, cataracts, etc) that may create blooming-style effects that are not caused by the display itself.