Lightroom CC: Smart Previews required? Option to not keep them?

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  • Updated 2 years ago
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I was wondering how much the new cloud-based Lightroom CC would take available disk space when using it as a native macOS app interface to my Synced Collections in LR CC 2015 but couldn't find any details about it.

So last night I installed new LR CC to my Late 2013 MBP 13" Retina with a 256 GB SSD, in LR CC app preferences changed Local Storage > Storage Strategy for Target Available Disk Space Usage to 5 % and let it sync. This morning I'm now seeing this warning message:
Low disk space: please clear some space or change your local storage settings.
Looking at Finder the Lightroom Library.lrlibrary file is 28,27 GB in size. Looking inside this package:
  • "Managed Catalog.mcat" file takes 1,14 GB
  • "originals" folder 0 kt
  • "previews" folder 59,6 MB
  • "proxies" folder 27 GB
  • "settings" folder 247 kB
So "proxies" folder is taking the most of the storage space with 27 GB. Inside "proxies" folder there's another folder called "2560" so I'm assuming new LR CC keeps 2560 px size Smart Previews locally.

My photos on new LR CC (synced photos in LR CC 2015):
  • 28.914 photos
  • 27 GB Smart Previews
Am I assuming right, new LR CC needs to keep Smart Previews of all synced photos? If this is true, could there be an option to not keep Smart Previews for all synced photos?

What I'd like new LR CC to be (for now) is a macOS native app interface to my Synced Collections and photos so that I don't need to attach my external SSD drive just to be able to browse my synced photos (and I don't have to have an internet connection as browsing via LR Web would need).
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Posted 2 years ago

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Photo of anssik


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Hmmm I don't get it. I did some housekeeping to my Synced Photos and reduced them from the 28.914 photos to only 18.575 photos. Now:

  • "proxies" folder is now 18,05 GB
  • but the Lightroom Library.lrlibrary file stays the same file size as before at 28 GB

How is this possible? How come the .lrlibrary still stays at 28 GB even though the proxies folder (aka Smart Previews) has lost almost 10 GB in file size?

I did close new LR CC and reboot my MacBook Pro.
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Victoria Bampton - Lightroom Queen, Champion

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Yes, the proxies are 2560px smart previews, so that the photos are editable even when you're not online. You could certainly put in a feature request to only keep smart previews for some, but I think you'd probably have more luck requesting the option to move the smart previews to another drive instead.

Sounds like macOS just isn't recalculating the size of the package file, if the contents don't add up to the total. I've seen that with other apps in the past too.
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Vagn-Ebbe Kier

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Victoria. Is i can understand it LRCC are working with smart previews connected to the original in the sky. Thus max. image working size is max. 100%. Which is sufficient for
adjustments,spots. etc. But I think the genius is if Adobe can make Export of adjusted picture the desired format Tif, Large jpg, directly fra the cloud, so you do not have to download and then export, which saves time and bandwith.
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Julie Kmoch, Sr. Development Manager

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Official Response
Note that the way we manage disk space is much improved since this original posting. Lr CC 1.0 did try to hold onto all smart previews but we found that it was still too much space to use sometimes. Current versions are much smarter about obeying the disk space slider in our preferences dialog.