MUTOH VJ-2638, Operation Manual

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Before using VJ-2638/1638/1638W OPERATION MANUAL
74 3.5 Test print
3.5.5 Color Verify (VJ-2638/1638 only)
The “Color Verify” feature can be utilized tov aid the printer operator in checking for and isolating
potential color reproduction variations before they become a visual detriment.
In this function, 14 color patches are printed, and the colors are measured by the optional
spectrophotometer (SPECTROVUE VM-10). If the Color Verify was performed before and the
measured value was saved as the baseline, the color difference from the baseline will be printed as a
result.
TIP
• Printer color reproduction can change over time due to various factors, including environmental
(shop temperature and humidity), age and storage conditions of ink and media, possinble lot-to-lot
manufacturing variations of ink and media, and aging of the printer itself (due to mechanical
wear).Individually, such factors may have minimal impact on color reproduction, but cumulatively
over a span of these factors can lead to color variations that become apparent and potentially
detrimental to image quality.
NOTE
• This function is not shown in VJ-1638W.
Follow the 2 steps below to check the color reproducibility using the Color Verify.
1. Save the baseline
• Perform the Color Verify under the concition* of comparison criterion, and save the measured
value (only one baseline can be saved).
*e.g.: To use a new media, after an initial ink charge, before starting the continuous print job, etc.
2. Check the current color reproducibility (Comparison with the baseline)
When a media or ink is replaced, or when the job that has been printed in the past, is printed again,
perform the Color Verify and compare the color with the baseline to check if there is no significant
change in the color reproducinility.
TIP
• When the Color Verify is executed, the color difference (dE) is printed on the top of each color
patch. If the color difference (dE) is quite large, it means that the color reproducibility has varied
from when the baseline was saved. In general, if the dE is more than 3.2, the color difference in the
print result will be visible.
• In this function, the color difference (dE) is calculated based on CIE 94*.
*CIE94 is proposed by CIE (International Commission of Illumination) in 1994.