# Two probably simple questions



## stuarts (Nov 2, 2018)

Hi all, I'm rather new to LR cc, so bear with me. Two questions:
--It looks like LR automatically generates two files during import, a full size JPEG and a half mb preview file. Is this normal, or am I doing something wrong?
--My impression was that the preview file and the original stay in sync, i.e. when I edit the preview file those edits are automatically synched to the original. But that isn't the case, it seems. The files do synch across my devices, but only with the same file type on each device, i.e. between my iPad and my desktop, the preview synchs with the preview, and the original synchs with the original. Is this the way the program is supposed to work, or am I missing something?
Thanks!


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## Jim Wilde (Nov 2, 2018)

stuarts said:


> --It looks like LR automatically generates two files during import, a full size JPEG and a half mb preview file. Is this normal, or am I doing something wrong?


I don't know if you are doing something wrong, but what you describe isn't normal. So let's start at the top....where are you importing from, a camera, a memory card, or existing files from a hard drive? You say that LR automatically generates two files, does that mean that after the import you see two versions of each file in the grid? Can you show us a screenshot of that, and then show us a screenshot of the Info panel of each image of one of these "pairs"?

Is it possible that LR imports two files because there are two files in the import source? Have you checked that?


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## stuarts (Nov 2, 2018)

Thanks for responding! I have a Nikon 5600 and the import is done either from that into my MacBook Pro, or to all of my devices through Snapbridge. The camera is set to save full size JPEGS only, not NEF and JPEG together. I've attached two screen shots:  1) the image on the top left, with the meta data (it's 477 kb); 2) the exact same image next to it, with the meta data, which is 6.7 mb. When I edit the smaller file, the larger file (the original presumably) doesn't change.


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## stuarts (Nov 2, 2018)

Maybe I am inadvertently importing the same image twice, from both the camera card and through the Nikon snap bridge, or Google pictures? Very confusing. Many of my pictures on different dates import only once, with the full size original, so there are clearly two sources.


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## stuarts (Nov 2, 2018)

I imported a picture from my hard drive on my  MacBook. It then appeared on my iPhone. I edited it on my iPhone, and the edits synced with the original on my MacBook! So I must have inadvertently been importing compressed versions as well as the originals for those sessions.


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## stuarts (Nov 2, 2018)

I think I have it now, thanks to your question. Smart Previews are only used on portable devices like the iPhone and the iPad, although you can download the original to those devices if so desired. On the desktop, you are editing the originals (if they are stored locally) or the smart previews, if they are not. Is this accurate?


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## Jim Wilde (Nov 3, 2018)

OK, glad you've sorted out the problem, which I suspected was because you were inadvertently importing two separate versions of the same image.

Smart Previews can be used on more that just mobile devices, they're used throughout the cloud ecosystem, either as a stop-gap until the original is loaded, or purely as a replacement for the original (depending on your settings). The point to understand is that Lightroom (Classic and LRCC) is a "non-destructive" editor, which simply means that the edits you make are never applied to the original file, instead they are stored in the catalog and applied to whatever preview is being used at the time....and there are various types of preview in use and different times, but they'll always show you the results of the edits while the original remains unaltered. When you export an image, a separate file is created which is derived from the original but with all the edits applied.

LR Classic also can use Smart Previews, which were originally intended as a means of editing images when access to the originals is unavailable, e.g. mobile on a laptop with the images on an external drive which is left behind. In that situation, provided the user has ensured that Smart Previews have been created beforehand, full edit capability is still possible. The current version of Classic in fact allows you to elect to work with Smart Previews even when the originals are online (there's a probable performance advantage in doing that).

If syncing images from Classic to the cloud, only Smart Previews are generated and uploaded, so for those images only the SP will be available on the mobile devices.


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## stuarts (Nov 3, 2018)

Jim, thank you again for your help. I have turned off the Nikon Snapbridge on my camera, and reverted to only the standard import from my camera card. I also deleted the smaller versions of the pictures (it was only one day of shooting that was imported with the small Snapbridge files as well as the camera originals). I can see the smart previews on my phone and my iPad, and the edits synch with the desktop versions. It's a great system. I bought Victoria's cc book and am learning the editing workflow.


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