3nh ColorChecker 24-Color Calibration Target Plate

Overview

The 3nh ColorChecker 24-Color Calibration Target Plate is a precision-engineered optical reference standard designed for quantitative color evaluation, white balance validation, and ICC profile generation in imaging systems. Based on the internationally recognized X-Rite ColorChecker Classic architecture, this target consists of 24 spectrally stable, pigmented matte-finish color patches arranged in a 4×6 grid. Each patch is formulated to replicate real-world surface reflectances—including additive primaries (R/G/B), subtractive primaries (Y/M/C), six neutral gray steps (10–90% reflectance), human skin tones, and natural object colors (foliage, sky blue, orange, etc.). The plate operates on the principle of spectral reflectance calibration: by capturing the target under controlled illumination, users establish a known ground-truth reflectance dataset against which camera sensor responses, display gamuts, and printer output can be objectively measured and corrected. It is not a light source or emission device; rather, it serves as a passive, Lambertian reflectance standard traceable to NIST-traceable spectral data.

Key Features

• 24 precisely formulated, UV-stable pigment patches with matte finish to minimize specular reflection and glare
• Consistent spatial layout (4 rows × 6 columns) with alphanumeric labeling (1–24) for unambiguous patch identification
• Physical dimensions: 290 mm × 204 mm — optimized for full-frame DSLR/mirrorless capture at 1:2–1:4 magnification
• Neutral gray scale includes six steps (L* ≈ 10, 20, 30, 40, 50, 60 per CIELAB) enabling grayscale linearity verification
• Manufactured under ISO 9001-certified production processes; batch-specific spectral reflectance data available upon request
• Compatible with standardized lighting geometries: 45°/0° or 0°/45° illumination/viewing configurations per ISO 13655

Sample Compatibility & Compliance

The 3nh 24-Color Calibration Target is compatible with all digital imaging platforms requiring color fidelity validation: industrial machine vision cameras, broadcast-grade cinema cameras (ARRI, RED, Blackmagic), scientific CMOS sensors, flatbed scanners, and medical endoscopic imaging systems. Its spectral reflectance properties comply with ASTM E308 (computing CIE tristimulus values), ISO 17321-1 (color management—characterization of digital still cameras), and ISO 12233 (acutance and spatial frequency response testing). When used in GLP/GMP-regulated environments (e.g., pharmaceutical documentation imaging or clinical dermatology photography), the target supports audit-ready workflows when paired with calibrated light booths (D50/D65) and metadata-logged capture protocols. It does not meet ISO 13655 Annex B requirements for primary standard certification but fulfills secondary standard criteria for routine system verification.

Software & Data Management

The target integrates natively with industry-standard color management software including X-Rite i1Profiler, CalMAN, basICColor, and open-source tools such as Argyll CMS and DisplayCAL. For ICC profile generation, users capture a raw (linear, non-demosaiced) image of the target under uniform D50 or D65 illumination, then import the TIFF into profiling software. The software maps measured RGB sensor values to corresponding CIELAB or CIEXYZ reference values (provided in standard .txt or .csv format with each unit). All processing must occur in linear gamma space prior to tone mapping. The target supports FDA 21 CFR Part 11-compliant workflows when used with validated software that enforces electronic signatures, audit trails, and version-controlled profile archives. No proprietary drivers or firmware are required—operation is entirely hardware-agnostic.

Applications

• Digital camera and lens characterization: quantifying chromatic aberration, color crosstalk, and spectral sensitivity deviations
• White balance algorithm validation across six preset modes (Auto, Daylight, Shade, Tungsten, Fluorescent, Manual)
• Monitor and projector calibration verification using patch-based delta-E (ΔE₀₀) analysis
• Print proofing and press calibration: evaluating dot gain, ink trapping, and substrate metamerism
• Computer vision pipeline validation: training data bias assessment and color constancy model benchmarking
• Forensic and archival digitization: establishing long-term color stability baselines for cultural heritage objects

FAQ

What lighting conditions are recommended for optimal use?
D50 (5000 K) or D65 (6500 K) illuminants are required. Use dual 45° incident lighting to ensure uniform irradiance across the target surface; avoid direct specular reflection into the lens.
Can this target be used for absolute radiometric calibration?
No. It is a relative reflectance standard—not a radiometric source. Absolute calibration requires NIST-traceable integrating sphere measurements.
Is the target suitable for outdoor daylight capture?
Yes, provided the scene is shaded and illuminated by consistent overcast sky (CIE standard overcast daylight). Direct sun exposure causes non-Lambertian behavior and metamerism errors.
How often should the target be replaced?
Under normal storage (dark, low-humidity, ambient temperature), pigment stability exceeds 10 years. Replace if physical abrasion, yellowing, or gloss development is observed.
Does the target include spectral reflectance data?
Yes—each unit ships with a QR code linking to its batch-specific CSV file containing 380–730 nm reflectance values at 10 nm intervals, referenced to NIST SRM 2010.