[DominikHoffmann]

I am a new user of Adobe Photoshop Lightroom. I am managing a library of around 500 photos with it, annotating each photo with keywords. Now, I would like to export these, with the keywords embedded in each JPEG file, which the Export command does. However, I am not sure whether, if I choose a quality of 100, Lightroom re-encodes all images with minimal compression or simply makes copies of the originals without re-encoding. Obviously, the latter would be preferable, as the former might possibly increase the file sizes over those of the originals.

Dominik Hoffmann

[peeb]

If you are ever likely to edit these, you should think about using a lossless compression format rather than JPEG.

[DominikHoffmann]

Originally Posted by peeb 

If you are ever likely to edit these, you should think about using a lossless compression format rather than JPEG.

Sure. I understand. However, I did not myself shoot those images, and I received them as JPEGs, rather than RAWs. The only edit desired is the addition of keywords to the files.

Either way, without wanting to sound pedantic or sarcastic, your reply doesn't address my question, or does it?

[DominikHoffmann]

I just looked at the size of the collection of files in the original library, versus the export. The original collection occupies 650 MB, and the collection exported as JPEGs with a quality of 100 comes in at 1.6 GB. This confirms my original suspicion.

[peeb]

No, I'm sorry, I didn't answer your question, but I was wondering whether you might be better off exporting them as a lossless format, rather than JPEGs, since I think that Lightroom will re-encode them.

[DominikHoffmann]

I just did the export to ZIF-compressed TIFF. The resulting collection uses 5.7 GB. That's far worse than Quality 100 JPEG compression.

[peeb]

Right, but also lossless. I find LZW works best.

[Veltliner]

Originally Posted by DominikHoffmann 

Sure. I understand. However, I did not myself shoot those images, and I received them as JPEGs, rather than RAWs. The only edit desired is the addition of keywords to the files.

Either way, without wanting to sound pedantic or sarcastic, your reply doesn't address my question, or does it?

You are just missing out on the main point of Lightroom if you don't shoot RAW.

You can adjust a RAW image much better, much more, and you have a digital negative, to which all changes are added in sidecar files, which leave the original unchanged.

Any change you make to a JPEG reduces its quality.

If you import into DNG, the new universal RAW format, you will have access to your pictures many years from now.

Certainly, you can export RAW files in JPEG, and you can choose the size/quality level in the export window.

[DominikHoffmann]

I have since found the answer to my question. The procedure I now follow is as follows:

1. In Lightroom, I choose Metadata->XMP->Export XMP Metadata to Files.

2. I launch PictureSync. As the source folder I choose the location of where Lightroom stores my images, which now have the XMP metadata embedded. As the destination I choose a folder, rather than a photo service like Flickr. I then choose "Copy to folder" as my destination and select the folder I want to use. I click on the "Export" button and uncheck the "Resize to..." option, as I want my images unchanged. I then click on the "Choose folder..." button and select my destination once more (I don't know why I have to do this), and off it goes.

In the process, PictureSync converts each image file's XMP metadata to IPTC, which is recognized by iPhoto.

Dominik

[verseguru]

Originally Posted by DominikHoffmann 

2.In the process, PictureSync converts each image file's XMP metadata to IPTC, which is recognized by iPhoto.

Some notes on usage of PictureSync with Lightroom if you want to save into your original files:
—You can drag and drop images onto PictureSync itself. (Do not do this from iPhoto.)
—You only have to choose File>Save Annotations to embed the IPTC, you don't need to use Export/Copy to folder. (You can set this to occur automatically in Preferences>Annotations>Save when opened.)
—You may want to enable the Window>Rules>Swap Title/Object rule, as Lightroom muddles these up.

See this page for more details. Note that this workflow will not write to the XMP sidecars, and if you re-open the files into PictureSync it will only read from the sidecars unless you disable that preference.