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Camera Support #11037

Noise profiles for Olympus m4/3 cameras require a "dummy" ISO 100 entry.

Added by Joel Brandt about 3 years ago.

Status:
New
Priority:
Medium
Assignee:
-
Category:
Darkroom
Target version:
-
Start date:
05/26/2016
Due date:
% Done:

0%

Affected Version:
git stable branch

Description

I recently noticed very bad noise reduction applied to an image, and discovered that it was the result of the profiled denoise module failing back to generic mode due to the RAW file reporting a "fake" ISO value below the lowest profiled one. Adding a duplicate ISO 100 entry in noiseprofiles.json fixed the problem.

As hinted at by the submitter of the noise profile for the E-PL 7 (#10429), recent Olympus m4/3 cameras don't have a real ISO 100, the base ISO being 200. The values below that are only "used" in extended or "low" auto-ISO mode, and are implemented digitally during JPEG generation. The RAW files reporting ISO < 200 are (unlike their JPEG versions) identical to ISO 200 files.

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