Blooming Test

Click or press F for fullscreen
Mode
Block size
Reading Scale
  • Halo <1 character — excellent (2304+ zones)
  • Halo 1-3 chars — good (1152 zones)
  • Obvious trailing halo — 384 zones / edge-lit
  • OLED — pixel dimming, zero halo

Professional Blooming Test

Moving block

White block racing across black at three sizes and speeds — halo width is easy to measure.

Subtitle mode

White-on-black text bar reproduces the most common movie halo scenario.

Starfield

Random small bright dots test how local dimming handles pinpoint light sources.

What Is Blooming?

Cause

Dimming zones are larger than the content; one bright dot lights the whole zone, creating a halo.

Zone count

More zones = smaller zones: 384 shows clear halos, 2304+ approaches pixel-level.

vs Backlight bleed

Halos follow bright content; bleed is fixed at screen edges regardless of content.

How to Use

01

Dark room, fullscreen

Kill ambient light and click the canvas to go fullscreen.

02

Switch three modes

←→ cycles block/subtitles/starfield, ↑↓ adjusts speed.

03

Measure the halo

Use subtitle character width as reference and compare with the scale.

Backlight Types

Mini LED 2304+

Flagship zones

  • + Tiny halos
  • + High peak brightness
  • − Expensive

Mini LED 384-1152

Mainstream

  • + Good value
  • − Subtitle halos visible

Direct-lit

Dozens of zones

  • + Cheap
  • − Large white wash

OLED

Pixel-level

  • + Zero halo
  • + Infinite contrast
  • − ABL limiting

Optimization Tips

Set local dimming to High in the OSD for movies — contrast improves visibly.

Disable local dimming for office/coding to avoid flickering halos around UI.

Drop dimming one level if game HUD elements show distracting halos.

Subtitle-sensitive viewers can use gray subtitles or lower subtitle brightness.

FAQ

Test Environment

  • Fully dark room (halos show best)
  • Use your normal brightness setting
  • OLED should show zero halo in this test
  • Watch from your usual distance

Related Tools

Add this test to the Test Wizard

Join the Wizard →