Skip to main content
Inspiring
August 21, 2023
Question

Good way to clean up old previews?

  • August 21, 2023
  • 3 replies
  • 12897 views

Lightroom Classic 12.5, Windows 11 Pro

 

My Previews.lrdata "file" seems abnormally large.

 

I had Lightroom delete any Smart Previews that might be lurking.  I believe it found 72, and they're gone.

I did the same thing with 1:1 previews, so they're gone.

 

A search in the previews file shows around 250,000 preview files (standard?), which is 2 - 3 times the number of images in the catalog, about 70,000 of which haven't been updated since 2020.

 

Is there some intelligent way to remove old standard previews and other junk in the previews file rather than deleting the whole thing and making Lightroom start over?

I presume Lightroom always deletes any previews associated with a file it deletes, but is there a way to check or have Lightroom check that orphan previews DON'T exist in the catalog - and delete any that are there?

This topic has been closed for replies.

3 replies

Inspiring
August 29, 2023

In the end I concluded that the simplest solution is probably the best.  I went back to having 2 catalogs.  One for "good" images that have been culled, and one for Incoming images. 

It would be nice if there was a way to import from one catalog to another, so all the stuff that's catalog-only and not persistent in the metadata would get moved too, but I haven't found a way to do that.

Abambo
Community Expert
Community Expert
August 29, 2023
quote

In the end I concluded that the simplest solution is probably the best.  I went back to having 2 catalogs. 


By @DavePinMinn

That is, in my eyes, a complex solution. But if it works for you…

quote

It would be nice if there was a way to import from one catalog to another, so all the stuff that's catalog-only and not persistent in the metadata would get moved too, but I haven't found a way to do that.


By @DavePinMinn

Whatever that means… When I'm travelling with my laptop, I use an external disk, where I import my catalog into my main system. Unfortunately, not all catalog data get imported (like publish services) so that I have an alternative solution for my two desktops.

ABAMBO | Hard- and Software Engineer | Photographer
Inspiring
August 29, 2023

It has some advantages...  It separates the previews from the real catalog from the Incoming stuff where there's a LOT of 1:1 preview generation and fiddling while doing culling.  And when there's nothing in that catalog, I can blow away the previews file and everything is clean for the next import.

It also makes it automatic to send the good images to the backup when I import them into the real catalog.

It was always pretty painless, except for losing stacks, when I used it, but I kept reading "you should only have 1 catalog", so I tried it.

 

When you get home from traveling and import your catalog into the main system, can you import a SINGLE folder into the main catalog or do you have to import the WHOLE catalog every time? 

Conrad_C
Community Expert
Community Expert
August 21, 2023

Not sure, but it might help to run File > Optimize Catalog. That’s supposed to clean up the database, and things like orphaned database entries. But I’m not sure how thoroughly that extends to the preview files that the database manages. However dj_paige is correct that there are probably multiple preview files per image, at the very least a standard preview and a grid thumbnail size preview, but more likely previews at multiple zoom levels and grid sizes that might have been used.

 

I just give up and throw out the entire .lrpreviews when it gets too big, even though that causes a delay when they are rebuilt as I view each folder again.

Inspiring
August 21, 2023

Thanks for the replies...  Yes, as the original topic said, I DID the Delete 1:1 previews AND Delete Smart Previews.  Those are all gone presuming the deletes worked.

 

The catalog gets optimized every time I back it up, which is weekly.  I'm not sure how thorough it is either.

 

If the only answer is to blow away the whole previews when it get unwieldy and rebuild it, I'll probably go back to a separate catalog for incoming images.  Only the "good" images ever got imported into the actual catalog and I didn't see the rapid growth.  And when there were no images waiting for culling, I could delete the previews file on the Incoming catalog and it was clean.

 

KR Seals
Community Expert
Community Expert
August 22, 2023

Is your issue with the large number of previews the size they take on disk? On a Win 11 machine, it should be possible to replace the C: drive with a larger one or add an additional (large) SSD that you can use to run LrC and the previews from.

 

One solution to the issue of LrC taking all that time to create previews is to not import the whole shoot if you are going to cull a large amount of the images in LrC. I do a pre-cull on my images from large shoots with Photo Mechanic which is very very fast at copying the images to the specified drive/folder. It is also FAR faster than LrC for culling. That way, LrC does not have to make previews of images that will just be culled out and deleted.

 

Ken Seals - Nikon Z 9, Z 8, 14mm-800mm. Computer Win 11 Pro, I7-14700K, 64GB, RTX3070TI. Travel machine: 2021 MacBook Pro M1 MAX 64GB. All Adobe apps.
Legend
August 21, 2023

In the Library Module, use Library->Previews->Delete 1:1 Previews


Typically, Lightroom Classic generates several different sizes of previews, which can be the reason you have 250,000 when you have about 70,000 images.

Inspiring
September 6, 2024

In the past the different size previews of an image were included in one file - the .lrprev file. As I understand, from a different thread, the use of separate size preview files only started in LR 13.5. DavePinPin is using LE 12.5, so the extra files he has should not be separate size previews. Its easy to see - just look in a preview folder. If it has all .lrprev files, there should only be the same number as your images. If it has loads of separate size files with no extension, then each image file should result in several several size files. My LR13.5 has produced six preview files for each image, with -80, or -160, or -320, or -640, or -1280 or -2560 at the end of each name.

After converting .lrprev files to the new format files, my LRC left 1349 .lrprev files untouched. I deleted these as I believed they were orphaned previews. After doing this I ran the 'Build Standard Previews' command  and it said there were none missing, and LRC runs fine.

 

bob frost