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If the paper white value is larger than 1.5 dE00, you might want to try a different spectrophotometer measurement condition. (see below). If the measurement condition is correct, and paper white L* is slightly high (less than 1), and b* is slightly bluer (up to 2 units lower) than the target paper white; this can be corrected with a little bit of yellow paper tint. Yellow paper tint will lower the L value of the paper slightly and are not visible to the eye.
If the color gamut is not large enough, you might want try a higher Total Ink Limit value. (see below).
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