What is the difference between the IA ECG B1C and B1C X profiles?

Both are 7-color CMYK+OGV ICC profiles from the Idealliance ECG kit, but they were built with different amounts of Gray Component Replacement. B1C uses more black and less cyan, magenta and yellow (more GCR). B1C X uses more cyan, magenta and yellow and less black (less GCR), which makes separations appear fuller and darker.

What is GCR and why does it matter?

Gray Component Replacement substitutes black ink for the equal parts of cyan, magenta and yellow that would otherwise produce a neutral. Higher GCR means less coloured ink is used, which lowers ink cost and generally makes the job more stable on press because neutrals depend less on the balance of three inks.

Which ECG profile should you print with?

It depends on priorities. The higher-GCR profile prints with less ink and is more manageable on press against color shifts. The lower-GCR profile produces a fuller, darker result through the tonal range. The two are not perfectly equal in color, so the choice is a genuine trade-off.

Difference Between IA ECG B1C and IA ECG B1C X ICC Profiles

Context: This analysis examines the two ICC profiles included in the Beta ECG Characterization Target and Kit released by Idealliance in August 2021. As noted at the time, these were beta profiles, not finalized standards. Idealliance — now part of PRINTING United Alliance — has since published an Expanded Gamut 7-color dataset and profile, and work on the final standardized litho and flexo ECG datasets has continued. Check the current ECG project page for the latest files. The GCR comparison below still holds as an illustration of how gray component replacement changes a separation — which is the point.

As part of the Idealliance ECG Beta Characterization Data Set download, there are two different ICC profiles — both 7-color (multichannel), CMYK plus Orange, Green, and Violet.

One is called IA ECG B1C. The other is IA ECG B1C X. The difference between them is how they were built: different amounts of GCR (Gray Component Replacement) were applied.

The CMYK Curves Inside Each Profile

Here are the CMYK curves from within each profile.

IA ECG B1C — more Black, less Cyan, Magenta and Yellow. This is the profile with more GCR applied (commonly called "ink savings").

IA ECG B1C X — the opposite: more Cyan, Magenta and Yellow, less Black. Less GCR.

Separated Images, Side by Side

Here are RGB images converted (separated) in Photoshop using both ECG profiles — B1C X on the left, B1C on the right.

B1C X (left) vs. B1C (right).

The side-by-side is honestly less striking than toggling back and forth, where the difference jumps out. B1C X appears darker, because it's fuller throughout the tonal range.

Channel by Channel

Now look at each individual channel — this is the content that would land on each plate. In order: C, M, Y, K, O, G, V.

Cyan channel separation compared between the IA ECG B1C X and B1C profiles — **Cyan** — B1C X (left) vs. B1C (right).

Magenta channel separation compared between the IA ECG B1C X and B1C profiles — **Magenta** — B1C X (left) vs. B1C (right).

Yellow channel separation compared between the IA ECG B1C X and B1C profiles — **Yellow** — B1C X (left) vs. B1C (right).

Black (K) channel separation compared between the IA ECG B1C X and B1C profiles, showing more black in B1C — **Black (K)** — B1C X (left) vs. B1C (right). This is the channel where the GCR difference shows most: B1C carries noticeably more black.

Orange channel separation compared between the IA ECG B1C X and B1C profiles — **Orange** — B1C X (left) vs. B1C (right).

Green channel separation compared between the IA ECG B1C X and B1C profiles — **Green** — B1C X (left) vs. B1C (right).

Violet channel separation compared between the IA ECG B1C X and B1C profiles — **Violet** — B1C X (left) vs. B1C (right).

You can clearly see that the B1C X profile puts more content on all of the color channels and less on the Black channel — exactly what you'd expect from a profile with less gray component replacement.

Which Profile Should You Use?

It depends on your priorities. Here's the trade-off:

	IA ECG B1C	IA ECG B1C X
GCR	More	Less
Black usage	Heavier	Lighter
CMY usage	Lighter	Heavier
Ink cost	Lower	Higher
Stability on press	More manageable — less prone to color shift	More susceptible to shift
Appearance	Lighter through the tonal range	Fuller, appears darker

The B1C profile will print with less ink and be more manageable on press against color shifts. But be clear-eyed: the results are not perfectly equal in terms of color. That's the trade you're making.

I was already exploring down this rabbit hole and thought others might be interested in the specific differences.

Thinking About ECG?

If you're interested in implementing expanded color gamut printing, get in touch. We offer a complete ECG ink set for offset and flexo, turn-key proofing and soft-proofing, and the training and expertise to help you implement it.
dang@aldertech.com

The CMYK Curves Inside Each Profile

Separated Images, Side by Side

Channel by Channel

Which Profile Should You Use?

Thinking About ECG?

About the Author

Dan Gillespie