Q: What is SCCA?
A: SCCA stands for Substrate-Corrected Colorimetric Aims – a standard mathematical formula based on the human visual phenomenon of chromatic adaptation – that simulates how CIELAB aim values (or a whole characterization dataset, or a printed image) would appear on a substrate different from that on which it was originally printed. 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. This is why SCAA is also referred to as “substrate-relative”.
Q: When filling out the Submission form, what does Relative mean?
A: Relative is SCCA (Substrate-Corrected Colorimetric Aims) ON.
Q: When filling out the Submission form, what does Absolute mean?
A: Absolute is SCCA (Substrate-Corrected Colorimetric Aims) Off.
Q: Can a proof be submitted for G7 Grayscale or G7 Targeted compliance?
A: No. All G7 Master proof submissions are treated as “color-accurate” proofs and therefore must meet G7 Colorspace compliance, accurately simulating a specific CRPC or color space.
Q: Is Idealliance mandating M1 measurements?
A: No. Idealliance is not mandating M1 measurements. Regardless of the CRPC (Colorimetric Reference Print Condition) at which a submitted print sample is aimed, the applicant may specify that the sample is measured in M0, M1 or M2, with the following understandings:
- G7 Grayscale is substrate-relative and therefore not dependent on the measurement mode. G7 Grayscale submissions may be measured in M0, M1 or M2.
- GRACoL 2006 was based on M0 but can also be measured in M1 or M2 mode if submitted as a “relative” match, i.e. with SCCA On.
- GRACoL 2013 and the other six CGATS.21 / ISO 15339 CRPCs are based on M1, but can also be measured in M0 or M2 mode if submitted with SCCA On.
Submissions that do not use SCCA will be measured in the M mode on which the target CRPC is based.
Q: Are we losing the ability to use older measurement devices? Is Idealliance mandating that I update to newer M1 measurement devices?
A: No. Idealliance will still accept uploaded data measured with any device, but the printed samples must be measurable on the devices available at RIT (see G7 website for the current list). There is no requirement for users or G7 Experts to upgrade to a new device. Keep in mind, however, that media with significant OBA (Optical Brightening Additive) content are best measured with newer M1 devices, if they will be viewed in newer, full-UV D50 viewing booths.
Q: Are custom test forms allowed?
A: Yes. You may change the supplied test forms in any way you like so long as you include the current QR code and the following:
- For G7 Grayscale submissions, either the P2P51 target or a custom target containing columns 4 and 5 of the P2P, in a format readable by the testing facility (see “Are custom targets allowed?”).
- For G7 Targeted submissions, either the P2P51 or a custom target containing columns 4 and 5 of the P2P and the six solid CMYRGB patches, in a format readable by the testing facility (see “Are custom targets allowed?”).
- For G7 Colorspace submissions, either the P2P51 plus the IT8/7.4 target, or the new TC1617 target, or a custom target containing all the unique patch values of the IT8.7/4 target and columns 4 and 5 of the P2P51 target, in a format readable by the testing facility (see “Are custom targets allowed?”).
Q: Are custom targets allowed?
A: Yes, but note that using the supplied Idealliance P2P51 and IT8/7.4 targets, or the TC1617 target is cheaper.
- You may use custom versions of these targets under the following conditions;
- The new target must fit on the automated equipment available at the testing facility.
- The application must supply an i1Profiler-compatible reference file which enables the custom target to be measured on the equipment available at the testing facility.
- The new target must measure at the same speed as a standard target.
- Custom targets should be approved by the testing facility prior to submission. To check if a target can be used please submit request to Margaret Hyman at mahasp@rit.edu.
- There is an additional $50 setup fee, per application, for each different custom target design submitted.
Note: If a target is submitted that has not been pre-approved and does not meet the above design requirements, any part of the application using that target will be deleted from the application without refunding the $50 fee.