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Question: Photos referenced library file size bigger than original image folder

I am running latest High Sierra on a Mid-2015 5K iMac. I have a folder of raw images with a file size of 432GB on an external thunderbolt drive. I have the same folders referenced in several different editing/DAM programs, this way I can train myself on different techniques without using more storage than necessary. I have been attempting to import the images into Apple Photos app as referenced images as that is the way my family would like to access the image. My belief is as with Aperture and iPhoto I could keep the smaller catalogue/library on my internal drive and thereby not take up more room on my internal.

The issue is when I attempt to import the images into Photos with the import photos to the library open unchecked I get a warning message stating Insufficient Disk Space Additional 1.32TB of free space needed to continue...

Everything I do, including creating new libraries, has the same result!

Any ideas? I understand Photos will create preview images, but 1.32TB from an original 432GB of images... :-/

Having scoured the web for an answer I have reached the conclusion, which I hope is wrong, that this is the way Photos works and it does not treat referenced images in the same way any other editing/DAM application does.

Any thoughts on this issue???

Thank you :-)

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Mar 14, 2018 2:23 PM in response to léonie In response to léonie

The external drive is 3TB Journaled HFS+, internal is 1TB Mac OS Journaled HFS+. I imported a folder of 262 raw images with the external folder being 4.08GB in file size. The new Photos library is 658MB and climbing quickly... Thanks :-)

Mar 14, 2018 2:23 PM

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Mar 14, 2018 2:41 PM in response to aussiearn In response to aussiearn

Extra info: I just went into the Photos library package and I see the previews in resources/media/master folder are between 3 - 5 MB in file size each... file name "fullsizeoutput_cc"

so basically a 12meg raw is converted into a 1/4 to 1/2 preview file... then I would expect the final library from a 432GB folder of images to be at the very most 216GBish...

Mar 14, 2018 2:41 PM

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Mar 15, 2018 2:38 AM in response to léonie In response to léonie

In addition to the sub folder ~/Photos Library.photoslibrary/resources/media/master/

you will also find large files for edited versions in

~/Photos Library.photoslibrary/resources/media/version/28/01/fullsizeoutput_12807.jpeg


~/Photos Library.photoslibrary/resources/proxies/derivatives/3c/00/3c5c/stale_largepv_3c 5c.jpg

Mar 15, 2018 2:38 AM

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Question: Photos referenced library file size bigger than original image folder