Recently I've encountered a problem scanning Astia on my new OpticFilm 120 scanner. The colors were off and hard to correct. After some research it turned out that the problem was caused by the metameric failure.
The solution is fairly simple: I had to create the ICC profile for each film type I use. To do that, I ordered IT8.7 targets and created profiles using Argyll CMS software.
Below you can see the IT8.7 targets with different ICC profiles applied. Color changes are most pronounced on OpticFilm 120 scanner which uses LED light source. The color changes are less pronounced on Epson scanner which uses CCFL light source.
Plustek OpticFilm 120
Below you can see the IT8.7 targets with different ICC profiles applied. Color changes are most pronounced on OpticFilm 120 scanner which uses LED light source. The color changes are less pronounced on Epson scanner which uses CCFL light source.
Plustek OpticFilm 120
| Film: Astia 100F |
Film: E100G |
Film: Provia 100F |
Film: Velvia 50 |
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| Profile: Astia 100F |
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| Profile: E100G |
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| Profile: Provia 100F |
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| Profile: Velvia 50 |
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Epson V750
| Film: Astia 100F |
Film: E100G |
Film: Provia 100F |
Film: Velvia 50 |
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| Profile: Astia 100F |
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| Profile: E100G |
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| Profile: Provia 100F |
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| Profile: Velvia 50 |
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Details
Each profile was created with following commands (Argyll CMS):
scanin -v -dn source.tif ...ref/it8.cht measurement.txt
colprof -v -A Plustek -M OpticFilm120 -C JaZ99 -D "description" -Zt -Zr -bn -nc -qh -ax source
where:
source.tif - tiff file with IT8.7 target scanned
it8.cht - file provided with Argyll CMS
measurement.txt - text file shipped with the IT8.7 target
source - name of source.tif file without .tif extension
By the way, average deltaE error (CIEDE2000) achieved is 0.1, max deltaE error is 2.9 (only on Astia target, on Dmax patch)
The jpg files on this page were created with following commands (convert command is part of ImageMagick software):
convert source.tif +profile "icc,icm" -profile profile.icc -profile sRGB.icm out.jpg
where:
source.tif - tiff file with IT8.7 target scanned
profile.icc - profile created by colprof command above
sRGB.icm - sRGB profile shipped with operating system
(note that first -profile option assigns the profile, second one applies the profile)
