Black Glacier

Shot on Provia 100F with GF670

Green mountain

Shot on Provia 100F with GF670

Axlarfoss

Shot with Fujifilm GF670 on Astia 100F

Glacier view

Shot with Fujifilm GF670 on Provia 100F

Metamerism and Scanners

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

	Film: Astia 100F	Film: E100G	Film: Provia 100F	Film: Velvia 50
Profile: Astia 100F
Profile: E100G
Profile: Provia 100F
Profile: Velvia 50

Epson V750

	Film: Astia 100F	Film: E100G	Film: Provia 100F	Film: Velvia 50
Profile: Astia 100F
Profile: E100G
Profile: Provia 100F
Profile: Velvia 50

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)

Originally posted on my web page: https://sites.google.com/site/negfix/metamerism.