# Color Management

_Technical References & Guides_

Color management runs through miscLab's capture, processing, output and archiving. It is not a separate retouching step, but a workflow built from equipment condition, light source, targets, ICC profiles, file space, output media and quality-control records.

We organize internal workflows with reference to FADGI 2023 Technical Guidelines for Digitizing Cultural Heritage Materials: measurable targets and analysis software verify system performance; stable ICC profiles and color spaces carry color; clear metadata records every process that deviates from the standard workflow.

## I. What FADGI Means for Color Management

| Item | Meaning in the miscLab Workflow |
| --- | --- |
| Goal | Make the digital file a trustworthy record of the original's condition at capture, rather than retouching the original into a more attractive image. |
| Method | Use targets, gray scales, color patches, resolution and uniformity tests to turn subjective appearance into reviewable system performance. |
| Star Rating and Project Goals | FADGI's star system describes image-quality goals for different tasks. miscLab selects the appropriate level of control for archiving, research, reproduction, publication or exhibition use, rather than forcing every project into the same level. |
| Validation Tools | Analysis tools commonly used in the FADGI ecosystem, such as OpenDICE, AutoSFR and Golden Thread, can check target readings, sampling frequency, color error, white balance, uniformity, sharpening and noise. |
| Recording Requirements | Any process that changes file appearance, such as stitching, sharpening, cropping, contrast adjustment, restoration, color recovery or local enhancement, should be noted in project records or file metadata. |

## II. Pre-capture Control

| Control Item | Working Method |
| --- | --- |
| Equipment Condition | Before formal capture, confirm that camera, lens, copy stand, light source, film holder, glass and software settings are stable. Rebuild configurations after system components change. |
| Light Source | Transmissive originals focus on light uniformity, brightness stability and reflection control. Reflective originals choose between even lighting, raking light and texture enhancement according to material. |
| Targets | For reflective originals, CDSG or project color targets can be placed on site. For transmissive originals, gray scales, color references or linearization workflows establish baselines according to media type. |
| ICC | Create or call a dedicated ICC for the current capture conditions. FADGI recommends maintaining consistency between devices, sessions and output spaces through system-level color management. |
| Working Space | High-quality masters default to ProPhoto RGB / 16-bit to preserve more room for later processing. Derivative files for web, preview or general communication are converted to sRGB. |

## III. Key Evaluation Metrics

| Metric | Control Focus |
| --- | --- |
| White Balance Error | Check whether neutral gray and white point have color casts. White-balance errors affect hue judgment across the whole set and make later mask removal more difficult. |
| Tone Response / OECF | Check whether tonal response from shadows to highlights is continuous and predictable, avoiding blocked shadows, prematurely clipped highlights or over-shaped curves. |
| Color Encoding Accuracy | Evaluate color encoding accuracy by comparing color patches with reference values. When color error is abnormal, first check light source, ICC, exposure, target condition and software conversion settings. |
| Lightness Uniformity | Check brightness uniformity across the image. Large originals, stitched scans and reflective-original lighting especially require attention to edge falloff and local reflections. |
| Dynamic Range | For positives, dense negatives, paintings and photographs rich in shadow detail, confirm whether the system can retain both shadow and highlight information. |
| Noise / Sharpening / SFR | Color management is not only about color. It should also avoid creating unrealistic detail edges through excessive denoising, sharpening or local enhancement. |

## IV. Differences Between Transmissive and Reflective Originals

| Object | Color-management Strategy |
| --- | --- |
| Reflective Originals | Paintings, photographs, books, rubbings and paper documents usually require faithful recording of the original's appearance under current lighting. Color targets, ICC, even lighting and project records are central. |
| Negatives | Negatives are not direct-viewing objects. Inversion and mask removal involve artistic intent, film characteristics and viewing habits. Standard masters prioritize linearity, high bit depth and reversible processing space. |
| Positives / Slides | Positives are closer to direct-viewing objects. The focus is density range, color accuracy, shadow gradation and highlight protection; HDR or bracketed exposure can be used when needed. |
| Special Transparent Media | X-ray film, wet plates, transparent film and intermediates require assessment of viewing method, density range and output goal before deciding whether to handle them as transmissive, reflective or hybrid workflows. |

## V. Output and Material Conversion

When a digital master enters fine-art printing or reproduction output, color management shifts from the capture side to the material side. The whiteness, ink absorption, gloss, fiber and transparency of different papers, fabrics, transparent media, canvas and xuan paper all change the final viewing result.

| Stage | Control Method |
| --- | --- |
| Print ICC | Common papers can use manufacturer ICC profiles or optimized profiles. Special media, transparent materials or important reproduction projects can use X-Rite i1Publish Pro 3 to create custom ICC profiles. |
| Rendering Intent | Choose relative colorimetric, perceptual or other conversion methods according to original color range, paper capability and reproduction goal, avoiding blind compression of highly saturated colors. |
| Proof | Proof key colors, grayscale, shadows, skin, paper white, lines and local texture before final output. |
| Output Resolution | The Epson inkjet system defaults to 360 dpi output. When source files are insufficient, they are assessed at 300 dpi; selected fine glossy media can be tested at 720 dpi. |
| Version Records | Keep records of material, ICC, output size, border, cropping, proof version and final parameters for reprints, review and long-term maintenance. |

## VI. Quality Control and Delivery

| Stage | Check Items |
| --- | --- |
| After Capture | Check whether exposure, white balance, target readings, file bit depth, color space, histogram, shadows and highlights meet project goals. |
| After Processing | Confirm that ICC conversion, linearization, mask removal, stitching, cropping, sharpening and restoration do not damage the integrity of the original record. |
| Before Output | Confirm paper, ink, ICC, rendering intent, size, viewing light and framing method. Important projects first receive partial or full-size proofs. |
| Delivery | Master files retain high bit depth and explicit color space. Distribution files are resized, compressed and converted to sRGB according to use. All non-default processing is noted in project records. |