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Black Level Test

Count visible patches 1-32 on black background. All visible = healthy. Missing low = crushed blacks.

Look for the gray patches on the black background. You should see all patches labeled 1 through 32. If patches at low numbers (1-5) are invisible, your monitor is crushing blacks - increase brightness or change the OSD black level setting.

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How to use

  1. Use Fullscreen patch grid in a dim room for the clearest read.
  2. If low-number patches stay invisible, verify GPU output is full range (e.g. NVIDIA Control Panel > Display > Output dynamic range = Full; AMD Display > Pixel Format = RGB 4:4:4 Full).

FAQ

Why 32 patches?

The reference pattern uses thirty-two 1-step grays from RGB 1 through RGB 32 on pure black—matching common online black-level charts.

Introduction

Count visible patches 1-32 on black background. All visible = healthy. Missing low = crushed blacks.

Look for the gray patches on the black background. You should see all patches labeled 1 through 32. If patches at low numbers (1-5) are invisible, your monitor is crushing blacks - increase brightness or change the OSD black level setting.