Today Apple released OS X Yosemite v10.10.4 update that contains a fix for the Leica M Monochrom (Type 246) DNG files issue when using the Apple Photos app. Additional information can be found here:
- Improves networking reliability
- Improves Migration Assistant reliability
- Addresses an issue that prevented some external displays from functioning properly
- Improves the reliability of upgrading iPhoto and Aperture libraries to Photos
- Improves reliability when syncing photos and videos to iCloud Photo Library
- Addresses an issue that could cause Photos to unexpectedly quit after importing some Lecia DNG files
- Resolves an issue that could delay outgoing email messages in Mail
- Fixes an issue where a website could prevent the user from navigating away by presenting repeated JavaScript alerts in Safari