• Welcome to the Lightroom Queen Forums! We're a friendly bunch, so please feel free to register and join in the conversation. If you're not familiar with forums, you'll find step by step instructions on how to post your first thread under Help at the bottom of the page. You're also welcome to download our free Lightroom Quick Start eBooks and explore our other FAQ resources.
  • Dark mode now has a single preference for the whole site! It's a simple toggle switch in the bottom right-hand corner of any page. As it uses a cookie to store your preference, you may need to dismiss the cookie banner before you can see it. Any problems, please let us know!

LR 5 corrupting previews before my eyes !

Status
Not open for further replies.

jont-uk

New Member
Joined
Aug 11, 2018
Messages
8
Lightroom Experience
Intermediate
Lightroom Version
5.x
Lightroom Version Number
5.7.1
Operating System
  1. macOS 10.13 High Sierra
Hi ... am pulling together some concert photos for a client submission tomorrow and LR5 has just started corrupting my preview images ... were fine an hour ago when editing ... now it is randomly displaying a colour block across part or all of an image ...

As I select an image in the library to check/add keywords it may or may not corrupt the preview ...

I've stopped now and run optimise catalogue, quit LR, rebooted mac, etc but is still doing it ...

It seemed to start when my broadband went down and I lost the network connection to my NAS and it was unavailable to find the file I was working on... everything is back up now but it is still causing problems ...

Any ideas ? ... do I need to backup the catalog file or rebuild it ? ... or should I just rebuild the previews file in the LR folder ...

BTW I have just started doing this work and will upgrade to LR 6 or CC next week but want to make sure all teh shots I took on Thursday are going to be OK to submit tomorrow !

I've attached a screenshot to show the preview corruption

Thanks

Jon
 

Attachments

  • PreviewScreenSnapz001.png
    PreviewScreenSnapz001.png
    1,014.2 KB · Views: 255
Previews are separate from your catalog. They are located in the ‘catalogname previews.lrdata’. You can let Lightroom rebuild them by moving this file out of rhe catalog folder. I would first double check the connection to the NAS however, because that could cause this.
 
OK - thanks...

So I removed the previews database and let it rebuild ... it did that then corrupted another preview that I hadn't opened for a couple of days ...

What'smore concerning though is I exported a couple of sample pics and it export dthe same corrupted image as the newly corrupted preview ? .... surely that isn't what it's meant to do ?

It's almost as if the image manipulation data has become corrupted and that it what it is reading and then processing before applying to the original image o the NAS as it exports ?
 

Attachments

  • FinderScreenSnapz003.png
    FinderScreenSnapz003.png
    687.5 KB · Views: 208
Hi ... so I've now upgraded the LR5 catalogue to LR Classic CC (7 day trial) and the preview corruptions are still there ... however the original JPEG(s) are fine on the NAS ?

I've removed the previews lrdata file from the LR folder (again) and I guess it has rebuilt them - but the corrupted previews are still there ...

How do I force LR to look for the original file and do a clean preview ? ... I've tried stepping back through the 'develop' steps which I can see it changing 'under' the corruption layer but it doesn't remove the corruption at all ?

I've another gig that I shot last night that I will try to load in a new catalogue storing (a copy of) the originals on the Mac HD ... I'm hoping that I can at least move those into my mail catalogue at a later date when I get this resolved ? !

TIA
 
If you are seeing this "corruption" in the Develop module, the previews are not the problem.....LR does not use the existing previews when loading an image in develop, a new (temporary) preview is built every time you select an image, using the original image file. So the indications are that LR is having a problem when reading the files from your NAS, as Johan explained earlier, and what you need to do now is try to determine if the corruption exists in the original files, or is the result of read errors when trying to build the develop preview. Using the MacHD temporarily for new imports is a sound plan, and should rule out any corruption being caused in camera or during transfer from the camera, but for the existing files on the NAS have you tried rebooting the Mac and your LAN and then trying LR again?
 
Thanks Jim ... the Mac has been rebooted yes but not the NAS or the router - I'll try that in a couple of days when I've finished the current gig set off the Mac HD ... when I check a corrupted preview original on the NAS though (say in the finder window by hitting spacebar) it renders fine so something in LR seems to have got corrupted ?
 
Are the originals raw or jpeg? If raw, be aware that many file browsers will only show the embedded jpeg which the camera creates, they don't do a raw conversion, so it could easily be the case that the embedded preview is fine while the actual raw data is corrupt.

In any event, given that things were fine before you had the broadband dropout, I'm hoping that the originals are all OK and the problem is happening during the reading of the file by Lightroom.
 
You are most likely looking in the wrong place. I know that you are seeing the corruption in Lightroom but it is almost certainly not the cause - so fiddling with LR won't fix it.

There are two causes of issues like this. Software and Hardware.

Software can cause these issues in two situations...
i. There is a bug in the software. Not the case here as, if there was a bug in the code, many more people would be reporting it. They aren't, so that isn't the issue.
ii. Your specific install is faulty/corrupted. A reinstall will fix that and you have done that so it isn't the issue. That leaves...

Hardware (or faulty/corrupted hardware drivers). Faulty of failing hardware can cause corruption which will show up when you use certain software that applies a specific load to the faulty component. LR is memory and processor intensive so may manifest the problem even when some simpler software, such as an image viewer, doesn't.

Given the description I would suspect problematic memory or a failure of the HD where the previews are stored. However, as others mentioned it may also be read errors due to a faulty storage drive that the originals are stored on or during transfer to LR.
 
Thanks Dan ... so the question still is how do I ‘uncorrupt’ the images ? ... I have a backup of the original files on the Mac HD ... how do I get LR to look at that and rebuild the preview - and preferably apply the associated edits ?

Going forward I can dig out my old Thunderbolt LaCie drive and use that as a primary storage (and then backup to NAS) ... how do I migrate the linked files to that drive so that LR can ‘see’ them in the catalogue and keep the edit history’s (as oppose start over again!) ?

Mac is a 2014 MacMini with 1tb Fusion drive and 16Gb RAM running latest OSX High Sierra (up to date) ... NAS is a Dropbox 5n with 5x3tb Western Digital RED drives ....
 
Thanks Dan ... so the question still is how do I ‘uncorrupt’ the images ?
By finding and fixing the root problem. Using a different drive in place of the NAS is a good way to check if that is the problem but if it's not the cause then the issue will just continue to occur. You will also need to check the other links in the chain.

I have a backup of the original files on the Mac HD ... how do I get LR to look at that and rebuild the preview - and preferably apply the associated edits ?
If your image back-up is up to date and uses the same folder structure as your image store on the NAS you can switch to the back-up quite easily. You select the top level folder and right/Ctrl click and select Update Folder Location. Then navigate to the same top level folder of the back-up and select that. All the images and sub-folders will automatically be updated and the edits will apply automatically. (Assuming your back up files are named the same as the originals).
 
Thanks all - that seems to have fixed the issue :) ... will keep main photos folder on the TB drive directly connected to MacMini and a backup on the NAS :cool:
 
Status
Not open for further replies.
Back
Top