I’ve seen a couple of folks report this problem lately, so I thought I’d put out a general warning against performing this operation in Lightroom 1+. Here’s the scenario … You imported some JPGs. You brought them into Develop and made some adjustments. So far so good. You then think, “I don’t just want these changes to exist in Lightroom, and I don’t want to create duplicates by exporting copies, so I’ll export these right back to the source folder and overwrite the originals.” This is the bad part. You click the Export button on the export dialog and see this:

Problem Exporting Files

[click to view larger]

 

So, since you intended to overwrite the originals you are thinking, “Great, just what I wanted”, so you click Overwrite. The next thing you see is a popup that says “An error occurred while exporting”:

 An error occurred while exporting

Uh oh. You weren’t expecting that, so you click Show in Library and Lightroom shows you a special collection of “Error Images” which contains all the photos you just exported and they are all sporting new question mark icons. Now you are really concerned so you open a file browser and check the actual folder and find all the photos are gone.  Yep, gone as in deleted.

If you are used to working in a pixel-editor like Photoshop it is normal to save your edits back to the original file, so on the surface it sounds like it might just work in Lightroom too. But it doesn’t. The difference between Lightroom and Photoshop in this scenario is that your original photo is not actually open in Lightroom. What you see is a preview of your original. When you export copies Lightroom grabs the original, makes a copy and then applies the Develop adjustments you made. This produces a brand new file.

So, in our scenario we are asking Lightroom to replace the original with this new copy, but Lightroom needs that original to make the copy! The end result is that Lightroom removes the original to make room for the new version, but then has no file to use for creating the copy with your adjustments. Ouch!

Thankfully in Lightroom 2 beta the option to overwrite originals is turned off. If you attempt the same operation you will see this instead:

 Problem Exporting Files

[click to view larger]

The text now reads “Do you wish to skip the existing files or rename the exported files to avoid collision? You can not choose to overwrite the existing files since some of them are the source files.” I’d love to see the same functionality added into the next Lightroom 1 dot release.

If you are reading this because you just learned this the hard way let me first express my condolences, then direct you to a third-party application that has the ability to export JPGs from your preview cache:

LRViewer

The quality of the copy you can get from the preview cache will be determined by your File Handling choices on the Catalog Settings dialog, but they quality is sure to be 100% better than nothing.  Here’s hoping you never need it.