Background - I've been trying to dive quite deep into color management. Below are my thoughts on comparing several printer profiles for Epson Enhanced Matte on my Epson Stylus Pro 9900. (Hey, Enhanced Matte is cheap!) I reproduce a lot of artwork, but certainly print for photographers as well. I am extremely picky about artwork reproduction, and every step forward in color management is a gigantic timesaver.
Profiles Compared - I compare Epson's stock profile, ImagePrint 9's Profile Valet's (stock) profile, and custom profiles I made using my i1 Photo Pro 2 through both i1Profiler and basICColor print. For my custom profiles, I used 5837 patches, then 3536 patches in the 2nd iteration. Definitely overkill, but again, Enhanced Matte is cheap, and I'm trying to learn as much as I can on it to make other medias go smoother.
Comparison Method - I created a set of 442 RGB colors, under a nice distribution, with slightly higher weighting in shadow, highlight, and grayscale areas. I then assigned these RGB colors to each profile and printed them. (That is, each print had a patch for 35R/35G/35B, however that color would of course translate to different LAB colors.)
I then used BabelColor's PatchTool to compare the LAB values of what was intended to be printed on the 442 patch vs the measurements of what was actually printed.
ConclusionsI am severely disappointed to see no statistical advantage over using a custom target by either i1Profiler or basICColor print over the Epson stock profile. (Granted, this is using my randomly distributed 442 patch set, this is limited to Epson Enhanced Matte only and may not be indicative of trends on other medias.) Granted basICColor print's max error is lower than Epson's stock profile, but not by much, and both custom profiles have a much higher average, best 90%, and worst 10% deltaE's.
ImagePrint's profile is interesting. There are more accurate colors, but it's variance is ridiculous in my opinion. The maximum error jumps from around 11 for the other profiles to 16.4. So, ImagePrint's profile's advantage will depend on the image. For most colors, it will be much more accurate. But, when it's off, it's really off. As a side note, most of the colors it is really off with are in the red-orange area of the spectrum, which I've noticed is quite off on other medias when printing gamut tests, like the Granger Chart.)
Questions* I know profiles help with color translation but won't be completely accurate - however I'm surprised to see such a high average DeltaE. I never would have imagined it to be in the neighborhood of 4. Is this common?
* It it very unusual that the i1Photo Pro 2 & i1Profiler seem to have created an inferior printer target vs Epson's stock profile? (Granted, this is on the 442 random patch set I generated, so the true averge DeltaE of all colors could show a different story.)
* If I want to print a spot color (that I know the LAB value of, and it's in gamut), this means there's no way to get it substantially closer to correct other than cycling through hard proofs, no matter what hardware and software is obtained?
Data from BabelColor's PatchTool
(All numbers are DeltaE - CIEDE2000)
Profile | Avg (All) | Best 90% | Worst 10% | Sigma (All) | Sigma (Best 90%) | Sigma (Worst 10%) | Max Error (10th Pct) | Max Error (Median) | Max Error (90th Pct) | Max Error (95th Pct) | Max Error (All) |
Epson 9900 Stock Profile | 3.68 | 3.24 | 7.7 | 1.75 | 1.03 | 1.75 | 1.96 | 3.39 | 5.6 | 6.93 | 11.56 |
i1Profiler (5837 patches, then 3536 2nd iteration) | 4.03 | 3.55 | 8.39 | 1.8 | 0.98 | 1.66 | 2.42 | 3.65 | 6.28 | 7.78 | 11.33 |
basICColor print (from above i1Profiles measurements) | 4.39 | 3.89 | 8.93 | 1.89 | 1.12 | 1.26 | 2.6 | 3.94 | 6.91 | 8.98 | 10.83 |
ImagePrint ("epx9mk_epenhmatte_pph_rday.icm") | 2.14 | 1.42 | 8.66 | 4.21 | 3.31 | 5.66 | 0.56 | 3.14 | 7.34 | 9.30 | 16.43 |