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can i delete lrprev files?

4 Answer(s) Available
Answer # 1 #
  • Final Projects.
  • Delete Images.
  • Delete Smart Previews.
  • Clear Your Cache.
  • Delete 1:1 Preview.
  • Delete Duplicates.
  • Clear History.
  • 15 Cool Photoshop Text Effect Tutorials.
Answer # 2 #

In this exercise, we will learn about Adobe Lightroom Classic Understanding The Lightroom Catalog (.lrcat) File.

In this section, I want to spend a few minutes talking about the Lightroom catalog. The reason I think this is important is even though most of this is done behind the scenes, once you have an idea of how it is that Lightroom works, you can adjust your workflow, or you can improve your workflow to work with the strengths of the Adobe Photoshop Lightroom application.

Because once you harness the power of this application, and you can get through your photos fast. That is to say; you can work with your existing photos very quickly; you can give them to your clients and provide a faster turnaround rate. You can work with more clients because you have a quicker turnaround rate, your clients will be happier. You can also build up your business.

The way that Lightroom works is it creates something called a catalog. The catalog is just a regular file that exists on the system at only Lightroom knows what to do with the catalog doesn't store any photos. The catalog has its internal folder structure to point out all of the catalog's images' previews. Now Lightroom works with a catalog by catalog. That is to say, every time you change the catalog, you have to restart Lightroom to tell it that it's working with a new catalog. In this case, the catalog that we're working with is the new-minimal.

Let me show you what it means for the catalog to exist on the file system. So I'm just going to minimize this. I'm going to show you how it exists on my file system. Now very quickly, you can see that I have a couple of different folders. I store my Lightroom catalogs on the same drive, as I keep all my photos. This is a drive that I've configured for myself; it's technically a raid zero if you want to know. I also have a tier-three backup which I backup very regularly. So my photos and my Lightroom catalogs are also backed up automatically. Now the photos that I store, I store them in a year format. I also store them in a year, month, day format. Then, I also give a short description of who the client is and the actual photoshoot.

I do this because it makes it much easier for me to work with the file system's photos in my organizational way. All of my photos are in one place. Doing this helps me know if I want to backup anything. For example, in this case, the photo directory is going to be the most important one. This because it has all of my photos from 2003, all the way up to 2016, to where we are right now.

The other folder that I want to point out is the Lightroom catalogs folder. Now each of these folders is its catalog. So you can see, I only have about 18 different catalogs that I work with.

Now I used to have more. But then I've already I've trimmed out each of these catalogs because you know I've archived them because some clients don't need this stuff. And I've also moved on with the certain kind of work that I do. Now you can see this is the new minimal photo catalog and then the one-to-one catalog as well.

Because we opened the minimal catalog, that was the one we're working on. You can see that when you open it up, it has a journal and a lock file.

These are two files that Adobe Photoshop Lightroom keeps for its internal purposes. That is to say, the lock file is created every time catalog is open. So you know this is the active catalog. The journal is a way for Lightroom to work with its database to let you know of the changes that it's making to the catalog as you're working on it. These two files will be created and destroyed every time you open and close Adobe Photoshop Lightroom.

The catalog file is the LR cat file. It is the catalog that has all the metadata. Now you'll notice the catalog itself for those 82 photos that we work with is only about 2MBs to 2.2. MBs, so it's quite small. All of those photos total about 240 MB or so. So the catalog itself is quite a lot smaller than all of the photos. That lets you know that the photos are not being stored in the catalog. What else is stored along with the catalog is probably information pointing to all of the previews folders. Now the previous folder is done in hex. It goes from zero to F with a database for its previews.

Then, each of the files has its internal file structure.

These are all LRPREV files or LR preview files.

These are all JPEGs, and they're all images. It just has its file extension that is native to Adobe Photoshop Lightroom. Now, these previews are something that Adobe Photoshop Lightroom takes care of it by itself. So you don't have to do anything about that. All you have to do is work with Adobe Photoshop Lightroom. Let me open it up.

All you have to do is work within Adobe Photoshop Lightroom, add to your catalog, and it'll take care of all of the rest of the things that it needs to do. So once again, just to quickly recap what we've learned, Adobe Photoshop Lightroom stores its photos in something called a catalog. The catalog doesn't have any of the images. It has pointers to the files to the locations of the files. Wherever the images are, and locations to the previews that it stores along with the catalog. The lock file and the journal file are internal to Adobe Photoshop Lightroom. These are the files that it uses to make sure that it's working. Nobody else can adjust each of these files. Nobody can corrupt the Lightroom catalog as well.

The other thing that I want to mention is that I store my photos in year format, and then also in a year, month, date with a small brief description of who the shoot was for and the date of the shoot and things like that. This is just for my internal record-keeping purposes. This is also how I work. I find that this, for me, has been the best workflow. So once again, the Lightroom catalog is stored in an LR cat file. And it's just a folder on the file system with a few extra files that it needs to work with. The images themselves are stored in a different location that the Lightroom catalog goes ahead and looks at. This is important. After all, you only want to work with the photos because you are a photographer and have a business to run. Or maybe you're just doing this for fun. Whatever it is, you don't want to worry about keeping track of where all your photos reside and ensuring that you store one Lightroom catalog in the right place. Because Lightroom will take care of all of that, it'll take care of all of the metadata associated with each photo, and it'll take care of all the storage that it needs to do. It'll do that all by itself.

Stanley Underwood
Sound Engineer
Answer # 3 #

Yes! That “Lightroom Previews.lrdata” folder (looks like a file on Mac) can be deleted without losing any of your photos or any of the editing work you have done in Lightroom Classic. Though there are some side effects to be aware of (see below). It may not be named exactly “Lightroom Previews.lrdata”, it could be “My Catalog Previews.lrdata” if you named your Lightroom Catalog “My Catalog”.

If video is more to your liking, scroll to the bottom of this post for a YouTube video that covers everything in this article.

Here is how you delete the Lightroom Previews.lrdata folder and have the Develop module remain accurate and fast (see Side Effects below):

Now let’s go through this in more detail so you really understand what you are doing when you delete the Previews.lrdata folder.

Simply put, this Previews.lrdata folder is where Lightroom Classic puts all the previews it builds and uses in the Library module. You know, those previews built as you import your photos. Well, you may not know it actually. So let’s go over that here as well.

If you have ever imported raw files into Lightroom you know that it can be pretty slow. Like 30 minutes or longer if you have a few hundred to a few thousand. By default, Lightroom Classic is configured to build something called “Standard Previews” when you import your raw photos because the Develop module needs them to show what is happening as you make adjustments to your photo.

Pro Tip: Slash up to 90% your import time using the Embedded Preview Workflow Adobe added to Lightroom Classic back in 2017 and still works incredibly well today!

This Previews.lrdata folder is where Lightroom Classic puts those Standard Previews. Lightroom Classic also creates 1:1 Previews if you ever zoom in to 1:1 or closer (e.g. 2:1, 3:1) in the Library module and it puts those Previews into this folder as well. Lightroom Classic is going to be creating these Previews all the time either on import or as you use the Library module. You can delete it using the steps above, or you can contain it a little using Catalog Settings.

Adobe does give you a few options that can be used to contain the size of the Previews.lrdata folder. The configuration options are in the Catalog Settings dialog box (Win: Edit>Catalog Settings, Mac: Lightroom>Catalog Settings).

On the File Handling tab of the Catalog Settings dialog box you can see how big the Preview Cache currently is. This is a screen shot of that dialog for my own Lightroom Classic catalog as of this article. I have 114,956 photos in that catalog and the Previews Cache (the Preivews.lrdata folder) has 94,631 previews in there. Let me explain each of the things in the Preview Cache portion of this dialog box.

You can have Lightrooom limit the size of the Preview Cache by changing the Standard Preview size to something smaller, and/or the Preview Quality to something lower. I have found it quite useable on my 2K display (2560×1600) to use pixel dimensions of 1440 and quality of medium. However, there is a reason Adobe set these things this way be default so you’ll have to decide what you are comfortable with.

The way to have Lightroom Classic keep the Preview Cache as small as it can is to use that last option, the “Automatically Discard 1:1 Previews”. If you are really worried about it you can change that option from the default of 30 days to 1 week or even 1 day. Lightroom Classic will then purge those significantly larger 1:1 previews from this cache at the interval you specify there.

You can also ask Lightroom Classic to purge all of the 1:1 Previews immediately by doing this:

Yes, this can help contain the amount of storage this folder will take on your hard drive some, but the problem is Adobe hasn’t given us any way to purge the Standard Previews from this folder and that is probably what is taking up the most space on your hard drive.

Why doesn’t Adobe give us the option to purge Standard Previews? It’s because Lightroom Classic really needs those Standard Previews for it to function correctly, which brings us to the side-effects you need to know about deleting this folder.

No, there is no free lunch. It is true that it is safe to delete the Lightroom Previews.lrdata folder. Safe in that by deleting the folder you will not lose any of your photos or the adjustments you have made to your photos and Lightroom Classic will simply rebuild the folder. However, you have now deleted all of the Standard and 1:1 Previews that were built as you used the software to edit your photos.

Unfortunately, Standard Previews are not an optional thing for Lightroom Classic. It must have them in order to show you how your image looks with adjustments applied in the Library module. If you delete the Lightroom Previews.lrdata folder, you delete all of those previews and now Lightroom Classic has to re-build them before it can properly show you your images in the Library module.

Not the end of the world for sure, Lightroom Classic will happily rebuild those Previews it needs as you use the software. Just be aware that the Library module will behave more slowly as you go back to work on photos.

B.S. Jaffer
Answer # 4 #

All the images you are showing in the Grid view area are MISSING. They are not where LrC thinks they should be.

If you had shown the Folder section I bet whatever folders (and drives) listed in that section would have a question mark next to them.

If you want help you need to start helping by showing the FULL LrC Library module with Relevant sections displayed. Like this. And you can collapse the Navigator section so other sections can be displayed.

Karsten Lenzey