I’m a professional photographer and I have a confusing problem with corrupt photos. Even though this technically probably isn’t Lightroom problem, I could not think of a better place to ask and part of the question is related to Lightroom file handling. The problem coincided with upgrade to Lightroom CC 2015-1, but I can’t tell if it’s in any way connected.
In short, a month after downloading and processing a large amount of RAW CR2 photos, many of them have corrupted. I only learned this yesterday when I wanted to export them.
Corruption looks like this: http://www.justphotos.ca/errors/MEM404067.jpg
The photo is not mine, but the problem is similar. Part of the photo looks normal, and part is destroyed. Ratio varies.
I performed following diagnostics:
- CheckDisk from Windows Explorer, including a surface scan - no problem detected
- inspecting SMART information from the hard drive (via Crystal Disk Info) - the drive checked out as “good”, with no parameter obviously alarming (although I’m no expert)
- checked RAM with memtest86 - no errors
- AVG virus and rootkit scan - nothing found
- Explorer and Lightroom can normally manipulate the files (copy, read, even develop), it’s just that they’re corrupt
Most important question first: does anyone know what can cause this type of corruption and avoid detection by all of the above mentioned tests? What to do about it?
Presumably, if there was an issue with hard disk SATA cable or motherboard
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Here’s a bit more background where things get weirder and where someone with LR knowledge might come in handy.
The disk in question is a WD 4TB with tens of thousands of photos. I checked a lot of folders randomly and so far found corruption in only two, chronologically one after the other (which may mean they are adjacent on the hard drive, but it also may not if it was significantly fragmented). There may be others, viewing RAWs after deleti
Photos were taken a month ago. I copied them manually to a master drive (internal) and to a backup drive (USB external, I only connect it for backups). I viewed all photos in Lightroom and post processed a few hundreds. They were all fine. After that they justsat there for a month with not activity and no viewing (ie. I can’t know exactly when they went corrupt).
After postprocessing, I used a software for synchronizing folders from master to backup drive. It copies new files, existing files which are newer or which have a differing file size.
Next question is crucial, so please help me shed some light on it. Does Lightroom IN ANY WAY modify CR2 files themselves? I know it creates XMP sidecars. But will it under any circumstances ever modify the master RAW file?
This is important because I know for a fact that original flawless RAW files were manually copied to backup disk. The synchronizing software would not copy corrupt files from the master drive unless they were changed somehow.
As far as I know, regular disk corruption is invisible to the OS or filesystem - when it occurs, neither file size nor date of modification are modified - only the original physical data on the hard drive plate.
It may be of academic importance right now, but I need to know to possibly modify my backup solutions for the future.
Thanks for any suggestions!