The second RIP calibration step is to linearize the ink channels with their newly restricted ink limits. This generates a set of curves that should produce a tonal response that is rich in shadow color and neutralizes the combined gray axis. The problem here is that many RIPs are still using curve generation algorithms that were created a long time ago and haven’t been updated. These RIPs rely on the final profiling process to “fix” an imperfect linearization, and the results are “good enough” for many.
The G7 process introduced an excellent way of automating the curve generation process for neutralizing gray axis that is especially useful to achieve press standards compliance like GRACoL and FOGRA. High densities are limited so as to achieve press specification.
G7 software makes decent linearization curves for 4 color large format processes as well. Here we choose not to limit high densities to better preserve the extreme shadows we love with fine art processes. For processes with additional channels (red, green blue, etc) we can make the linearization curves elsewhere. Some inks like dyesub are a little strange and the black ink can be colorful. In these situations G7 won’t produce neutral B&W prints and a composite all-color Lab linearization is needed.
The final result of an all-color Lab linearization is gorgeous, natural tonality with deep shadow color Ana neutral gray axis that is better suited for profiling. Once we get around to making a profile, it won’t have to try as hard to correct an imperfect linearization.
Email us if you’d like to talk more about linearization or ChromaMax calibration at your location.
