Leica specific information

Leica M8 and M9 DNG files have a section of data known as the MakerNotes encoded into them. Thanks to the work of Carl Bretteville, it is now possible to decode this information. Cornerfix can do two things with the information:

1. Print out all the data. CornerFix automatically prints out a decoded version of the MakerNotes to the logging window, similar to this:
2. Leica MakerNotes
3. Selected user profile: 4
4. White Balance Preset: Auto or manual
5. Lens Id: Uncoded/Not detected
6. Frame Selector Position: Uncoded/Not detected
7. Blue Dot Brightness: 6.671875
8. TTL Brightness: 5.136719
9. Leica Estimated Aperture: f/9.5
10. CornerFix Calculated Aperture: f/8.0
11. System temperature: 23 C
12. Color temperature: 5515 K
13. CCD Sensor Id(?): 0
14. CCD Board Id(?): 1
15. Controller Board Id(?): 0
16. M16C micro-controller Id(?): 0
17. UVIR Correction: Not Active
18. Update the EXIF file. CornerFix has the ability to update the DNG file's EXIF (and XMP) data to show both the estimated aperture (for any lens) and the Lens Id (if the lens is coded). Note that:
    1. The aperture value used to update the EXIF data can be either the Leica g-stop value (the “Leica Estimated Aperture” value), or a CornerFix calculated estimate based on the “Blue Dot” and “TTL” values, rounded to ½ stop increments. This calculation, which is based on analysis of a large library of images, should be more accurate than the Leica value, as described in Carl Bretteville's paper. However, some users have reported that in their particular situation, the Leica value is more accurate. In order to select which to use, either enable or disable the “Use calculated aperture” option setting.
    2. Not all Raw Developers show the Lens Id string, which is stored in XMP format, even if it is available – notably, while Lightroom does, Apple's Aperture does not.
    3. In order for the EXIF and XMP data to be updated, you must have the “Update EXIF” option in the “MakerNotes” preferences enabled. If this is enabled, whenever you save a file, or batch convert files, the EXIF data will be updated, regardless of whether you have a lens profile loaded or not.

Batch Updating EXIF data

If you run Cornerfix without a lens profile loaded, it will just update the EXIF data (if enabled), and regenerate the thumbnails embedded in the images. So, in order to only update EXIF data without devignetting images, simply do the following:

1. Double-click on cornerfixw.exe to start it. Do NOT load a CPF file!
2. Enable the “Update EXIF” option.
3. Select the image files you want to correct by going to File->Batch Correct Images. You can then select a group of images, either by using the Cnrl-click to select individual files, or shift-click to select a range. Note that all files must be in the same directory. CornerFix will then cycle through all the selected images. The converted images are written as the original file name with “_CF” added to the filename. At the end of the conversion process, all image files are unloaded, but the option settings remain loaded.

Warning: Any files with same name as a newly corrected file (the original name plus “_CF”) will be overwritten without warning!!!