Can a .dng file be viewed in Photos?

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Level 2

272 points

Can a .dng file be viewed in Photos?

The reason I ask is I am scanning old film with Silverfast software which writes .dng files for later processing. When opened in Silverfast the encoded image is displayed. When viewed in the Finder or Photos the files have a generic image. I asked about this on the Silverfast support site, and was told it is an Apple issue.

My understanding is that files with extension .dng contain RAW data, in a format created by Adobe with the intention of creating a standardized digital archive format. I would think an image cataloging application, such as Photos, would be able to display images which are in a standardized archive format. Photos, and other image precessing applications which use OS X system libraries, can work with RAW image data in many proprietary formats. To me it seems strange that Apple supports many proprietary format RAW image files, but not a RAW format intended as an archive standard.

I have requested Apple support .dng files. The support I want is for the Finder and Photos to display a thumbnail of the encoded image.

Am I missing something?

(Earlier I mistakenly posted this question in the iPhoto area.)

OS X Yosemite (10.10.3)

Posted on Jun 26, 2015 4:09 PM

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Answer 1

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léonie

Level 10

194,895 points

Jun 27, 2015 11:38 AM in response to Tom Ritch

I have plenty of DNG files in my Photos library and Photos can develop the files and edit and display them. And when I export them, the FInder will display the thumbnail of the image.

But the results will probably on the encoding of the DNG file. The Photos RAW format support page (OS X Yosemite: Supported digital camera RAW formats - Apple Support) does not mention DNG format at all. My DNG files have been migrated from Aperture to Photos, and the Aperture RAW format page states: Apple - Aperture - Technical Specifications - RAW Support

" Aperture also lets you work with most DNG files.1

Aperture works with most DNG files generated from cameras that support this format and with DNG files generated by the Adobe DNG Converter with the “Convert to Linear Image” option turned off."

Probably this restriction will also al´poly to the DNG files in Photos.

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Answer 2

Tom Ritch Author

Level 2

272 points

Jul 6, 2015 3:39 PM in response to léonie

Thanks for the information, léonie. Hearing how DNG files work from someone who uses them is helpful. I think you confirm what I thought, that the DNG "standard" format varies, so all DNG files are not all readable by any application that can read one kind of DNG.

I understand that the DNG format is not a closely defined standard because it is extensible. I understand that an extensible format is important for storing RAW data, because camera innovations may continually create new types of RAW data. I suppose having software which creates RAW image data write the data to a semi-standard format DNG file facilitates hardware development, and that the semi-standard DNG files facilitates development of software to read the RAW data. This is all well and good for hardware development, as is one of Adobe's announced intentions for DNG files.

What would like to find is Apple software which can read DNG files created by Silverfast, and display the image. Silverfast HDR can display the images, but Photos cannot. This means that when I scan with SIlverfast to convert my film archives to digital archives I can't use Photos to organize the archive.

Apple, Adobe and Lasersoft Imaging (creator of Silverfast) work pretty well together. Hopefully in the future Apple will add the capacity to read Silverfast DNG files to its libraries. I have submitted a requested to Apple to add this capability.

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Answer 3

léonie

Level 10

194,895 points

Jul 6, 2015 3:46 PM in response to Tom Ritch

A reliable support for DNG files would be very helpful. Right now converting t TIFF is the safer option on a Mac, only the TIFF format is so wasteful and increasing the library size.

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