Recently, we have been trying to highlight various features within the SpotOn Analyze and Verify software that both users and non-users may not know exist.
What Is SCCA?
Substrate-corrected colorimetric aims refers to a mathematical formula that approximates the L*a*b* values on a different substrate.
According to the Idealliance site when describing SCCA:
“The value of SCCA in the G7 Master process is that it allows a print or proof made on a non-standard substrate to be judged for its “relative accuracy,” i.e. how it would appear to an observer in the absence of a comparison proof.”
That is why SCCA is referred to as substrate relative.
The SCCA Calculator
If you take a look at the image below, you can see that in this example of the calculator we are referencing GRACoL 2013 (CRPC 6). The L*a*b* values of the substrate (first column and row under the Analysis chart) are 95, 1, -4.
On the left, we can choose a test chart, like the TC1617, and measurement condition, like M1. In the fourth option down on that left-hand column, we can alter L*a*b* values for our desired substrate. In this example, we changed the b* value to -6 instead of -4.
Back under the Analysis chart in the second column, you can see how the SCCA calculator adjusted the values for CMYK, RGB, and neutral colors based on the desired substrate’s b* value change.
In the third column labeled “Deltas,” you can see the effect of the substrate change on the CMYK, RGB, and neutral patches.
SCCA in SpotOn
From the SpotOn startup splash screen, you can choose Settings (the wrench and gear icon in the image below).
Choose to change the settings of Analyze/Verify in the top menu and choose Tolerance Sets (highlighted in blue below). The ability to turn on substrate relative or SCCA is one of the options in a tolerance set. We suggest picking an italicized tolerance set (system default tolerance sets) that doesn’t have SCCA turned on (G7 Targeted has it turned on) in the list at left and making a copy of it (duplicate). Then you can turn on the SCCA option by checking the Substrate Relative checkbox and Saving that tolerance set with a new name. I usually add SCCA to the end of the tolerance set name so I know that SCCA is turned on for that tolerance set vs. the original where it is off.
When Should You Turn On SCCA?
When you verify your print and your problem areas are in the whites or lighter colors, it’s often due to the difference between the substrate being printed on and the reference set substrate. Try using the new tolerance set you just made that has the SCCA or substrate relative option turned on.
It’s important to note that substrate correction isn’t always the answer, but it can be a powerful tool in SpotOn Color just like the SCCA Calculator.