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White Level Test

Count visible patches 223-254 on white background. All visible = healthy. Missing high = clipped highlights.

Look for the gray patches on the white background. You should see all patches labeled 223 through 254. If high values (250-254) blend into white, your monitor is clipping highlights - reduce contrast or check the OSD.

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254

How to use

  1. Use Fullscreen patch grid with moderate ambient light so glare does not veil the brightest steps.
  2. Try lowering OSD contrast (~70–75%) if the top patches merge into clips before calibration.

FAQ

Do OLED panels behave differently?

Yes—ABL/APL can dim bright windows; rerun after the picture stabilizes and compare windowed vs fullscreen.

Introduction

Count visible patches 223-254 on white background. All visible = healthy. Missing high = clipped highlights.

Look for the gray patches on the white background. You should see all patches labeled 223 through 254. If high values (250-254) blend into white, your monitor is clipping highlights - reduce contrast or check the OSD.