L
lexaclev
Dear members,
This is my first post so first of all thank you all for valuable and helpful threads and advices in MSA topic. Most of my questions are already answered here, but I still need you collective wisdom in the field of instrumental color measurements.
The problem we ran into is GR&R for instrumental (spectrophotometer) measurements of white colored painted plastic auto parts. GRR for pure whites is almost twice as bad as for other colors and unacceptable for practical purposes. Measured values are dL, da, db and resulting deltaE. The troublesome component is dL with most between-appraisers variation. Same parts, same appraisers, same experimental plan as for other colors is used. GRR for all other colors is acceptable.
What might be wrong with white colors? Is instrumental control unreliable for them and visual inspection should be used instead? (BTW, customer requires instrumental control)
Thank you in advance for your help!
This is my first post so first of all thank you all for valuable and helpful threads and advices in MSA topic. Most of my questions are already answered here, but I still need you collective wisdom in the field of instrumental color measurements.
The problem we ran into is GR&R for instrumental (spectrophotometer) measurements of white colored painted plastic auto parts. GRR for pure whites is almost twice as bad as for other colors and unacceptable for practical purposes. Measured values are dL, da, db and resulting deltaE. The troublesome component is dL with most between-appraisers variation. Same parts, same appraisers, same experimental plan as for other colors is used. GRR for all other colors is acceptable.
What might be wrong with white colors? Is instrumental control unreliable for them and visual inspection should be used instead? (BTW, customer requires instrumental control)
Thank you in advance for your help!