Store LR Catalog Previews.lrdata on external drive?

[laurathistle]

My lightroom catalog previews.lrdata file is taking up a huge amount of space on my computer (207GB). I've read that if you delete this file, Lightroom will recreate previews when you open up the app. 

Has anyone tried storing the previews.lrdata file on an external drive when not using lightroom, and putting it back on the computer when you import photos/work in lightroom? So the previews file isn't permanently deleted and stays updated (by transfering it back and forth between computer and external drive).

[Rob_Cullen]

Never tried your suggestion! (not at all practical IMO)

If your external drive is relatively fast with ample free space- why not put your Catalog there also (with the .lrdata) and run the catalog from there? You will only need the drive connected, but never have the bother of transferring (207Gb) back and forth!

CATALOG-FIND AND MOVE

[Just Shoot Me]

Just Delete that previews file and as you say LR will recreated it the next time you start LR. BUT it will not have all the preview, LR will need to Recreate them. Which is OK. Because the reason your LR Catalog FOLDER, Not just the actual catalog.lrcat file, is so big is because of all the previews LR has created for ALL the files you have "VIEWED" (Viewed is the key word here). LR is Supposed to delete older preview (not just 1:1 previews) after a certain period of time but it doesn't so your Previews folder is holding LR created previews from 2-3-4-whatever years ago that you will never need.

Deleting the Previews folder clears those out and you start fresh with only a limited number of preview files for your most recent images (the images you View after LR recreates the Previews folders).

[JohanElzenga]

What you suggest does not make sense. Lightroom needs the previews file each time you open the catalog and look at images, not just when you import images. What you can do (if you know how to do this) is place the previews on an external drive and then place a symbolic link to that location inside the catalog folder on your internal drive. This works on two conditions:

1: it must be a symbolic link, not an alias (Mac) or shortcut (Windows)

2: the external drive must be connected when you start using Lightroom.

[D. Saunders]

Hello Johan, This is exactly what I want to do! - - put my LR previews file on an external drive and have a symbolic link to it from LR on my internal drive. I've looked all over the web for symbolic link info but can't get the syntax correct. How do I create a symbolic link please?! I'd appreciate specific info please. Thanks.

[D. Saunders]

Oh, some info - - -  I use LR and its files run from the ssd of my Mac laptop (MacOS Big Sur operating system). The previews are filling up the ssd drive so I'd like to figure out a way to access them on an external drive. However, I'd like to keep the LR program running on the ssd for the speed and so I prefer not to move all of LR program to an external drive if at all possible. (All my photos are accessed on an external drive.)

[Ian Lyons]

The more sensible (yes, sensible) approach is to put both the catalog and previews on an external SSD rather than split the two. Adobe chose to combine both in the same folder so as to avoid the need for customers futzing around or tying knots in handkerchiefs as reminders, etc.

A 512MB SSD will cost you $50-100 and should be plenty large enough for  the catalog and previews

[Sean McCormack]

I'd agree with Ian on this one, in fact it's the method I've used for quite a while. You can even go as large as 4TB SSD's for reasonable money now, though as the 512GB  should be more than enough for all but the largest catalogs and previews. Bear in mind this is not including the photos themselves. 

[D. Saunders]

Thanks also, Sean, for weighing in. Or when I replace my current 2TB non-ssd, perhaps it'll be with a 4TB Ssd. For LR, need all the speed I can get.

I just get tired of chucking out usable drives when the drain of intensive software like LR or its ever-growing capacity needs make newer (more powerful) drives almost a necessity. That said, it's good the more powerful ones do exist!

P. S. I did figure out the symlink & put the LR previews file onto the 2 TB non-ssd external drive. I'm curious to see how much lag is introduced by LR having to access the previews separately from the catalog. 

[D. Saunders]

Hi Ian,

Thanks. I understand your point completely but currently have a 2TB external drive (non-Ssd) that I'm already using & was looking to add the previews file to it rather than have an additional external drive on my desk. At some point, I may replace it with a 2TB SSD external drive for the speed and then move all my current files & the LR catalog (w/ previews file) so I have everything on just one external drive. 

[josephlavine]

My suggestion is to creat esmaller previews when importing. The default is to use a setting that is roughly the resolution of your monitor, but I find smaller works fine for previews and saves much space.

warmly/j