Hello Mike,
I don't have the ISO 15311 at the moment but the description of calculating the M-score from your screenshots provided a pretty good idea for the computation.
My understanding is you need to average the CIE L*a*b* value across the columns ( 46 columns) and rows (64 rows), then sum up the dE for the columns and the rows and multiply by 10 to get dE_short_line and dE_long_line respectively. Next is to get the dE_short&long by averaging the above dE_short_line and dE_long_line to get ready for the final M score computation.
Feel free to reach out to my email for any discussion.
Best Regards,
Jinkai Qian
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Jinkai Qian
Techkon USA
Danvers
(978) 777-1854
jqian@...------------------------------
Original Message:
Sent: 08-03-2020 04:18 AM
From: Leilei Yao
Subject: How to calculate M-Score respresenting Uniformity within a Press Sheet?
The M-score came from Idealliance digital press certification.
But I do not make it clear how to calculate it? Anyone know more details about it? Thanks in advance.
"The press sheets described above will be measured using colorimetry and the measuring geometry and configuration as stipulated in this document. The M-Score procedure is used as a pass/fail criterion for this test.
The M-Score is based on ISO 15311. The M-Score computes a single value, scaled from 0 (poor reproduction) to 100 (perfect reproduction), which correlates well with the perception of print variations for a uniform tinted test form printed on digital press systems. The following procedure is used to calculate the M-Score."
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Mike Yao
BrandQ Expert
G7 Expert
Fujifilm (China)
Shenzhen
86-15012558115
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