IT8 Myth Versus Fact: The Real Story Behind the Standard

The IT8 standard is a foundational specification for color calibration, input profiling, and process control in graphic arts, yet widespread misunderstandings persist regarding its current relevance, target device ecosystems, and day-to-day utility in modern digital workflows.

Understanding the IT8 Standard: Origins and Core Purpose

The IT8 standard refers to a series of specifications developed by the ANSI IT8 committee (Image Technology 8), which later transitioned under the administration of the International Organization for Standardization (ISO) as ISO 12642 and related documents. Created during the transition from analog prepress to digital publishing workflows in the late 1980s and 1990s, the primary objective of IT8 was to establish universal calibration targets. These physical targets—most notably the IT8.7/1 for transparent materials and IT8.7/2 for reflective paper—feature a precise grid of color patches with known colorimetric values (CIE Lab or XYZ coordinates).

By scanning or photographing an IT8 target under strictly controlled lighting conditions and comparing the device’s digital capture against the reference file supplied with that exact physical target, color management software can build an accurate ICC (International Color Consortium) input profile. This profile translates device-dependent RGB or CMYK values into a device-independent color space. The fundamental purpose of IT8 is to eliminate guesswork, ensuring that scanners, digital cameras, and printing presses interpret color objectively rather than subjectively.

Myth 1: The IT8 Standard Is Completely Obsolete in the Digital Age

A pervasive myth in modern photography and graphic design is that IT8 calibration targets are entirely obsolete relics of the drum-scanner era. Proponents of this view often argue that modern digital cameras, high-resolution CMOS sensors, and advanced raw processors handle color science automatically, rendering physical targets unnecessary.

While it is true that modern sensor technology and raw converters feature sophisticated default profiles, the core requirement for absolute color fidelity remains unchanged. In high-end archival digitization, fine art reproduction, medical imaging, and packaging prepress, automated camera profiles frequently fall short of the precise color accuracy demanded by industry specifications.

Furthermore, while spectrophotometers and automated target-reading software have evolved, the underlying mathematics of empirical profiling rely on the same comparative principles established by the IT8 specifications. An IT8 target provides a known physical truth against which an imaging system's actual capture errors are measured. Without physical reference targets, color management systems must rely solely on generic manufacturer profiles, which cannot account for lens variations, specific lighting spectral power distributions, or individual sensor aging.

Myth 2: IT8 Targets Work Universally Without Maintenance or Expiration

Another critical misconception is that an IT8 target is a permanent, lifetime investment that can be stored indefinitely and used repeatedly without degradation. In practice, IT8 targets are susceptible to environmental factors that alter their physical and colorimetric properties over time.

Physical targets are printed using photographic dyes or high-precision inks on specific substrates. These materials are sensitive to ultraviolet (UV) light, ambient heat, and humidity. Over time, dye fading shifts the spectral reflectance or transmittance of the color patches, rendering the original reference data file inaccurate.

Operators must store IT8 targets in dark, cool, dry environments, typically in light-tight envelopes or boxes when not in use. Manufacturers frequently print expiration dates or recommend replacement intervals—often between two to five years—to ensure that the physical patches continue to match the electronic reference data file supplied by the manufacturer. Using an expired, faded target introduces systematic color casts into every profile generated from it.

Myth 3: IT8 Applies Only to Scanners and Has No Relevance to Printers

Because the earliest and most widespread use of IT8 targets involved calibrating desktop transparency and flatbed scanners, many practitioners assume the standard is restricted exclusively to input devices. This represents a fundamental misunderstanding of the broader ISO 12642 framework and its ecosystem.

While IT8.7/1 and IT8.7/2 focus on input devices (scanners and cameras), subsequent parts of the standard and related graphic arts specifications—such as ISO 12642-2 (extended test chart with 928 patches) and ISO 12642-3—are designed for output characterization. These larger characterization targets are printed directly on a printing press or inkjet proofer without color management, and then measured with a spectrophotometer.

The resulting measurement data creates output ICC profiles that dictate how a printing device reproduces color. Therefore, the IT8 architecture bridges both input and output workflows, serving as the common language for end-to-end color management across diverse hardware vendors.

Fact: Precision Requires Strict Adherence to Measurement Geometry

One of the least understood aspects of utilizing IT8 targets is the strict requirement for geometric and lighting compliance during measurement and capture. An IT8 target is not a passive poster; it is a precision-engineered scientific artifact calibrated under specific measurement geometries, such as 0/45 or 45/0 for reflective targets (as defined by ISO standards) and diffuse illumination for transparent targets.

When users attempt to create profiles using irregular lighting setups—such as uneven studio strobes with high color temperature variability or consumer-grade LED panels with poor Color Rendering Index (CRI) scores—the resulting profile will incorporate those illumination flaws. Achieving accurate results with IT8 targets demands:

• Consistent, high-CRI light sources that match standard illuminants (typically D50 for graphic arts).
• Elimination of stray light, reflections, and flare within the scanning or capture environment.
• Precise alignment of the target within the imaging frame to ensure software patch recognition algorithms map data accurately.

Step-by-Step Implementation: Creating a Profile Using an IT8 Target

For practitioners seeking to leverage IT8 standards to build an accurate ICC input profile for a camera or scanner, following a rigorous procedural workflow is essential to prevent profiling errors.

1. Verify Target Condition and Reference File: Ensure the physical IT8 target is within its manufacturer-specified lifespan, free from fingerprints, scratches, or fading. Locate the specific text-based reference data file (often provided via download using a serial number unique to that physical target).
2. Setup the Capture Environment: Place the target flat on the scanner bed or mount it securely on a copy stand for camera profiling. Illuminate it evenly using calibrated D50 light sources, ensuring zero glare or hot spots.
3. Capture the Raw Image: Scan or photograph the target without applying any automated color correction, sharpening, contrast curves, or auto-exposure adjustments in the capture software. Save the file in an uncompressed format (such as RAW or unedited TIFF).
4. Process in Profiling Software: Import the target image into a specialized profiling application (such as ArgyllCMS, basICColor, or profiling modules within suite software). Crop the target boundaries carefully so the software can auto-locate the fiducial markers and individual color patches.
5. Generate and Verify the Profile: Link the captured patch values to the reference text file. Compute the ICC profile and save it to the system color directory. Test the profile by applying it to a known test image and checking neutrality in neutral gray patches and smooth transitions in skin tones.

Frequently Asked Questions

What is the difference between IT8.7/1 and IT8.7/2?

IT8.7/1 is designed specifically for transmissive media, such as 35mm and large-format color transparency film, used primarily with dedicated film scanners. IT8.7/2 is formulated for reflective media, such as photographic paper or graphic arts card stock, utilized by flatbed scanners and reflective copy capture systems.

Can I use a digital photograph of an IT8 target instead of a scanner?

Yes, photographing an IT8 target mounted on a copy board is a standard procedure for profiling digital cameras, copiers, and specialized industrial imaging systems. However, lighting uniformity, lens flare, and vignette control must be strictly managed to avoid corrupting the captured patch values.

Why do my profile results look worse after using an IT8 target?

Poor profiling results almost always stem from capture errors: applying automatic exposure or contrast adjustments during capture, using an expired or faded physical target, selecting the wrong reference data file for that specific target serial number, or suffering from uneven lighting across the target surface.

Are IT8 targets still relevant in a fully digital workflow?

Yes. While digital sensors have become more consistent, physical capture environments vary wildly based on optics, lighting, and media type. IT8 targets remain the gold standard for grounding digital image capture in objective, verifiable colorimetry.

Conclusion

The enduring utility of the IT8 standard lies in its ability to anchor digital imaging workflows in objective physical reality. While myths regarding its obsolescence or universal plug-and-play nature persist, proper application of IT8 targets, combined with strict adherence to environmental and geometric standards, remains vital for professionals demanding uncompromised color accuracy.