This seems worth some comments.
First -- experimenting is the best! Nothing is obvious without trying it.
So experimenting and trying things out is always recommended.
I'm not really sure where the numbers come from for the Curve 1 & 2 -- K, LK, LLK values so its hard to be sure.
(My initial feeling is the Curve 2 has the LLK too low -- like you used the .55 factor twice; but I'm not sure.)
Looking at the ink curves you can see that LLK for Curve 2 uses a lot more ink -- you said it was a lot lighter ink (.14 vs .25).
Then looking at the density curves -- what should you care about? Curve 2 is closer to "linear" than Curve 1 but these
curves are before Linearization so that's not the end result. My take would be that curve 1 is smoother and might actually be
the better one once you do the linearization. The little wiggles in curve 2 are harder to repair.
Linearize and then do the two graphs -- things will be a lot closer but the differences may tell you more.
Roy
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On Tue, Feb 4, 2025 at 08:40 PM, shileshjani wrote:
OK, so I did my experiment:
* Epson P900, OEM inks
* Only used PK, LK, and LLK on Epson Premium Luster
* Calibration printed at 70% density
* Lmin of LK was 55% step of K
* Lmin of LLK was 25% step of K
* Created curve #1, K=100%, LK=55%, LLK=25%. All limits at 70
* Created curve #2, K=100%, LK=55%, LLK=0.55 * 0.25 = ~14.
* Figure of curves below shows differences in Curves 1 and 2. But not
particularly instructive in-itself.
* Figure of printed L vs 5% steps much more decisive. The method of
referencing LLK to LK and reflecting back to K is much closer to linear than
my previous undertanding of the method.
* I kept "Gray Curve" settings at Highlight = 5, Shadow = 5, no Overlap, and
Gamma =1. The highlight and shadow values may impact results.
* I learned something.
