# Smart Previews



## JEB (Aug 17, 2021)

Hi,

I wonder if someone could explain* in simple terms *the role of smart previews in Lightroom *Cloud* *NOT* Classic. I use my iPhone 12 as my sole camera nowadays and use an iPad, desktop PC and laptop.

I understood that if editing an image within Lightroom Cloud on a mobile device you are doing so on a smart preview rather than the original DNG or JPG. When I look at the info tab it tells me that the image is a JPG/DNG.

I thought that editing using a smart preview even though the original was a RAW made no difference. I noticed in a post recently that if you wish to move to Photoshop to perform something then you should use the original which I suppose makes sense. How would you go about that assuming you had started out on say an iPad with a smart preview?

I would appreciate an explanation. I have not been able to find a full explanation in “Edit Like A Pro” and the internet gets Classic and Cloud so mixed up I find I can’t rely on it!

Thanks in advance.


John


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## Johan Elzenga (Aug 17, 2021)

If you send an image from Lightroom for iPad to Photoshop for iPad then the original gets downloaded if needed.


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## clee01l (Aug 17, 2021)

JEB said:


> Hi,
> 
> I wonder if someone could explain* in simple terms *the role of smart previews in Lightroom *Cloud* *NOT* Classic. I use my iPhone 12 as my sole camera nowadays and use an iPad, desktop PC and laptop.
> 
> ...


Lightroom Classic sends only Smart Preview DNGs to the cloud.  These are 2560 pixels on the long edge.   If you edit these  on a mobile device, you are editing the smart preview file and these edits will sync back to the original file in Lightroom Classic.  If you export or share from the mobile device you will export the proxy Smart preview image file. Smart Preview DNGs sent to the cloud from Lightroom Classic do not count against the plan storage limits .

If you take a photo using the mobile device camera or Import images from the mobile device to the Lightroom cloud, these will be full size images, either JPEGs HEIC, or RAW image files.   These will be stored full size in you Adobe plan storage limits.   These full size images will also sync down to Lightroom Classic and appear in your Lightroom Classic catalog.
JPEGs and TIFFs are not RAW but RGB images.  DNG can be RAW or RGB depending on the type of data in the data block.   If your camera creates a proprietary RAW file and you convert that to DNG on Import, It remains a RAW file.  If you create an HDR in LrC, LrC saves that as a RGB DNG image.   Some Cameras and mobile devices can create a RAW DNG image. 

So, you can have JPEG, Full size DNG (RGB or RAW), Smart Previews DNG, Proprietary RAW (like CR2 & NEF) stored in the Adobe cloud.

Depending on the source for these files, your Lightroom Mobile will be working with the Original (if sources locally) or a Smart Preview (if sourced from the Adobe Cloud)   No matter where the image originated, Lightroom Mobile will store the local edit instructions  With the image that is stored in the cloud.  These edits instructions will be applied to the image in the cloud and the original if the original is in a Lightroom Classic catalog.


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## JEB (Aug 17, 2021)

Hi,

Thank you for your reply, I do appreciate it.
However, I am NOT INTERESTED in Classic and as I understand there to be a difference in the way Classic and Lightroom (Cloud) deal with Smart Previews and the internet is full of confusion between the two products I am anxious to get this absolutely clear in my tiny mind.
Can I ask for further clarification based on my above understanding.
Much appreciated.
John


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## Paul McFarlane (Aug 17, 2021)

Johan has answered your  question. To elaborate, unless you tell your local device to hold the original, once it's uploaded to the Cloud a Smart Preview is available. If you then decide to edit it, as long as you're connected to the internet, the original is downloaded and used. Page 56 of your Edit Like a Pro covers this point.


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## JEB (Aug 17, 2021)

Thank you all,

I will try to get my mind round this.

I do find it confusing when talking about Classic and Cloud when I understood them to deal with smart previews differently.

Regards

john


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## Johan Elzenga (Aug 17, 2021)

JEB said:


> I do find it confusing when talking about Classic and Cloud when I understood them to deal with smart previews differently.


They don’t deal with them differently. Smart previews are proxies (small alternatives) for your originals. They can be used to edit images without needing to have the original on the device. The only difference between Lightroom Classic and the other Lightroom apps is that Lightroom Classic stores the originals locally, while the Lightroom ecosystem apps store the originals on the Adobe cloud servers.


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## JEB (Aug 17, 2021)

Paul,

I thought I would read what ELaP has to say about smart previews as you suggest but can’t find anything at page 56.
john


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## JEB (Aug 17, 2021)

Johan,
Thanks for that. That gets that misconception out the way!


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## mikebore (Aug 18, 2021)

JEB said:


> Hi,
> 
> I wonder if someone could explain* in simple terms *the role of smart previews in Lightroom *Cloud* *NOT* Classic. I use my iPhone 12 as my sole camera nowadays and use an iPad, desktop PC and laptop.
> 
> ...



My situation is similar to yours except I use Mac. My simple understanding, which I hope doesn't contradict any of the experts replies, is that there are two prime purposes of smart previews:

1. Speed and ability to edit off line  because no download required (unless with Photoshop, which Johan says needs full size original).

2. Reduced local storage.  My 82k pics library uses 90GB of local storage instead of 586GB needed for originals. This fits on my laptop which the originals wouldn't. (I do have my originals in a local backup independent of LR Cloudy).


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## Johan Elzenga (Aug 18, 2021)

mikebore said:


> My situation is similar to yours except I use Mac. My simple understanding, which I hope doesn't contradict any of the experts replies, is that there are two prime purposes of smart previews:
> 
> 1. Speed and ability to edit off line  because no download required (unless with Photoshop, which Johan says needs full size original).
> 
> 2. Reduced local storage.  My 82k pics library uses 90GB of local storage instead of 586GB needed for originals. This fits on my laptop which the originals wouldn't. (I do have my originals in a local backup independent of LR Cloudy).


Correct. One additional comment: if you have uploaded an image from *Lightroom Classic* to the cloud, then there will only be a smart preview in the cloud. If you then select that image in *Lightroom desktop* and choose 'Edit in Photoshop', you will get a warning that there is no original that Photoshop can open (_not even if you do this on the same machine that runs Lightroom Classic_!) and a question what you want to do: open the smart preview in Photoshop (meaning you will get a 2560 pixels wide copy in Photoshop) or cancel.


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## tspear (Aug 18, 2021)

I think a lot of posts/blogs over think smartpreviews as it related to Lr (Cloud ecosystem).
Smartpreviews are just a small JPG proxy for the original image, allowing simple editing, quicker downloads for connected devices, and reduced storage requirements. If you zoom in to 1:1 or attempt exports or send to Photoshop, than Lr tries to use the original image not the smartpreview. Depending on where you loaded the images, and Desktop settings (you can force all or some albums to keep originals locally), then Lr may already have a local copy of the original already cached. If Lr does not have a local copy of the original, it downloads it as needed. 
If Lr cannot download the original (e.g. you are offline), you get a warning message when you try and export (have not tried the other functions in this state).


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## JEB (Aug 19, 2021)

Good Morning,
Thank you all for your kind thoughts and information.
Can I just state briefly below what my understanding now is and ask you either to confirm or correct this.
If working with LR Cloud (let’s forget Classic please, unless absolutely necessary), all original images are stored in the cloud at the full resolution they were uploaded at, either as RAW, DNG, JPG, TIFF, PNG etc.
What we see on the screen of our device (PC/MAC Desktop/Laptop, iPhone, iPad) are smart previews.
You can request a full-size image from the cloud, if it is available. (Presumably both on Desktop and Mobile).
If on Wi-Fi and you wish to edit in PS then LR Cloud will automatically download and open the full sized version. Warning if not available.
While on the theme of warnings, I think I am going to have some further questions shortly. So you are warned!!
Cheers and thank again for all your help.
Regards,
John

PS Just noticed Tim's post above which appears to answer my post but...................?


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## Jim Wilde (Aug 19, 2021)

JEB said:


> If working with LR Cloud (let’s forget Classic please, unless absolutely necessary), all original images are stored in the cloud at the full resolution they were uploaded at, either as RAW, DNG, JPG, TIFF, PNG etc.



Yes.



> What we see on the screen of our device (PC/MAC Desktop/Laptop, iPhone, iPad) are smart previews.



Not always (in fact, probably rarely), as the behaviour is different depending on which app you are using. Specifically:

In Lightroom Desktop, normal grid and detail panel views are usually basic previews (probably Jpeg), not smart previews. If you have checked the Preferences option to "Store a copy of all smart previews locally", it MAY be that you would be viewing the smart preview in the grid or normal Display panel, though I suspect not, I still think you'd be looking at the basic preview. If no Smart Preview exists locally when you zoom into 1:1 or start to edit an image, Desktop will download the *original*, not a Smart Preview. In which case it's probably safe to say that the only value of the Smart Preview stored locally is when/if the desktop device is taken offline and you want to carry on editing.

In LrMobile, the behaviour is different. Assuming there is no local Smart Preview or Original, the user would be viewing the image via the basic previews. If you want to edit an image, the resulting behaviour depends on the Preferences setting for "Only Download Smart Previews". If it is enabled then as soon as you select the edit panel LrM will download a Smart Preview, which would be used throughout the edit process. If, however, that option is not enabled, LrM will download the original whenever you enter the Edit panel.



> You can request a full-size image from the cloud, if it is available. (Presumably both on Desktop and Mobile).



Yes in LrMobile, but in LrDesktop there is not a similar "Get Original" option. LrD has a "Store Album Locally" option, which would download originals of all images in the selected album, but for getting the original of single images you can force that simply by zooming to 1:1.



> If on Wi-Fi and you wish to edit in PS then LR Cloud will automatically download and open the full sized version. Warning if not available.



Yes, that sounds right. It certainly is in LrDesktop, and I assume that would be the case from LrMobile.  The same applies when trying to export using a resolution greater than the standard Smart Preview size (2560 px on the long edge), from either Desktop or Mobile,

Nobody's mentioned LrWeb, which is just as well as that is different to both Desktop and Mobile.


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## JEB (Aug 19, 2021)

Hi

Thanks to you folks I believe I'm making progress in my understanding of this topic.
Two steps forward and then one back!
What is the difference between a "basic preview" as opposed to a "smart preview" ?
John


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## clee01l (Aug 19, 2021)

JEB said:


> Hi
> 
> Thanks to you folks I believe I'm making progress in my understanding of this topic.
> Two steps forward and then one back!
> ...



In Lightroom Classic there is a Previews folder and there can be a Smart Previews folder. I think the only previews files available in Lightroom for the cloud are Smart previews. For me, basic Previews are found in the Lightroom Classic Previews folder.


Sent from my iPad using Tapatalk


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## Jim Wilde (Aug 19, 2021)

clee01l said:


> In Lightroom Classic there is a Previews folder and there can be a Smart Previews folder. I think the only previews files available in Lightroom for the cloud are Smart previews. For me, basic Previews are found in the Lightroom Classic Previews folder.


If you have used LrDesktop at all, you could then examine the local library where you would see separate sub-folders for "previews" and "proxies". The "previews" sub-folder would contain the "basic previews" that I referred to earlier, similar to the library previews in Classic. And obviously the "proxies" sub-folder would contain the Smart Previews.

@JEB  "Basic preview" generally means low resolution jpegs, which are not suitable for editing, best used for simple display purposes. "Smart Previews" are a form of DNG, which are "scene referred"....meaning they can be edited with the full range of flexibility that the original Raw file would have. The two preview types operate in much the same way as the library previews and smart previews do in Lightroom Classic.

The local catalog in LrMobile will also contain similar "basic previews", suitable for image display in the various viewing modes (Info, Rate & Review, Activity), but not suitable for editing....hence the need to download either a Smart Preview or the Original when you start editing an image.


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## Johan Elzenga (Aug 19, 2021)

This discussion once more illustrates that Adobe was wrong to use the name ‘Smart Previews’. Smart previews aren’t previews, they are proxies for originals. And because Lightroom is a non-destructive editor, neither originals nor proxies are changed when you make edits. That means that smart previews cannot be used as substitute for normal previews, not in Lightroom Classic, not in Lightroom desktop and not in Lightroom mobile. All versions of Lightroom use normal previews to show you the edited image.


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## johnbeardy (Aug 19, 2021)

I'd say that if you are not using Classic Lightroom, you should completely forget the term "smart preview" and avoid confusing yourself by asking about "basic preview".  You might even want to forget the word "preview"!

All you need to know is that the various cloudy versions of LR use  proxy files or access the originals, depending on what you are doing. The various apps will generally use the proxies first, but if you try to do something at full resolution, the app will try to access an original either by downloading it or by using a copy in its local cache.


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## JEB (Aug 19, 2021)

Hi,
I think I have now got a better understanding of the role played by and importance of Smart Previews, thanks to all you contributors for the information provided.
It would appear that for most users it is not worth getting overly concerned with all the details, as some of the more recent posts have suggested.
I really do appreciate everybody’s contributions. This is in my view an excellent forum.
I would like to make a couple of, what I hope, will be regarded as constructive observations.
I think it would be a shame if all of what has been said is just confined to history. It would, in my opinion, be good if this could be condensed by a competent individual, of which there appear to be many, and published somewhere for future reference. The logical place I suspect is “Edit Like a Pro”.
One final observation. When I raised this topic, I deliberately did so in the CLOUD forum hoping to avoid the general confusion between Classic and Cloud found in the wider internet but that was not the case.
Thank you all again. I will no doubt have further queries in the future and hope to receive your assistance then.
Regards
John


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## johnbeardy (Aug 19, 2021)

JEB said:


> One final observation. When I raised this topic, I deliberately did so in the CLOUD forum hoping to avoid the general confusion between Classic and Cloud found in the wider internet but that was not the case.


A brave attempt - though doomed not to succeed!


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## clee01l (Aug 19, 2021)

JEB said:


> One final observation. When I raised this topic, I deliberately did so in the CLOUD forum hoping to avoid the general confusion between Classic and Cloud found in the wider internet but that was not the case….


 I think the reason that you were doomed is because Both Lightroom Classic and Lightroom use the cloud and Smart Previews can originate in Classic and the “previews” in Lightroom aren’t obviously previews. The term Preview itself is probably the most confusing as the file sent to the device is the original or as Johan says a proxy for the original and develop instruction with the final rendered by the device or for the device. 


Sent from my iPad using Tapatalk


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## johnbeardy (Aug 20, 2021)

Life's too short to struggle with ill-chosen feature names.


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## tspear (Aug 20, 2021)

johnbeardy said:


> I'd say that if you are not using Classic Lightroom, you should completely forget the term "smart preview" and avoid confusing yourself by asking about "basic preview".  You might even want to forget the word "preview"!
> 
> All you need to know is that the various cloudy versions of LR use  proxy files or access the originals, depending on what you are doing. The various apps will generally use the proxies first, but if you try to do something at full resolution, the app will try to access an original either by downloading it or by using a copy in its local cache.



Only problem is Adobe has "Smart Previews" in multiple locations in Lr.


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## tspear (Aug 20, 2021)

johnbeardy said:


> Life's too short to struggle with ill-chosen feature names.



lol, especially when it comes to Adobe. I have never seen a company make such horrible naming choices that cause them to spend so much time addressing it. I sometimes think it is some Machiavellian plan by the marketing department to generate noise in the marketplace.


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## JEB (Aug 17, 2021)

Hi,

I wonder if someone could explain* in simple terms *the role of smart previews in Lightroom *Cloud* *NOT* Classic. I use my iPhone 12 as my sole camera nowadays and use an iPad, desktop PC and laptop.

I understood that if editing an image within Lightroom Cloud on a mobile device you are doing so on a smart preview rather than the original DNG or JPG. When I look at the info tab it tells me that the image is a JPG/DNG.

I thought that editing using a smart preview even though the original was a RAW made no difference. I noticed in a post recently that if you wish to move to Photoshop to perform something then you should use the original which I suppose makes sense. How would you go about that assuming you had started out on say an iPad with a smart preview?

I would appreciate an explanation. I have not been able to find a full explanation in “Edit Like A Pro” and the internet gets Classic and Cloud so mixed up I find I can’t rely on it!

Thanks in advance.


John


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## johnbeardy (Aug 20, 2021)

Honestly, that thought has crossed my mind.


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