Ad
Ad
Ad
Pages: [1]   Bottom of Page
Print
Author Topic: purpose of the LRcat. file versus xmp ?  (Read 1548 times)
zobelinski
Jr. Member
**
Offline Offline

Posts: 72



« on: June 11, 2011, 06:25:08 AM »
ReplyReply

hi there,
i recently posted on the x100 forum what i learned in the LL-LR tutorial, that the xmp files should always stay with the raw files and that they contain all the info LR needs to work with them in terms of adjustments, metadata and so on.
now somebody has pointed out that this is not necessary, that all this info is also stored in the lrcat file and the xmps are only needed for other programms such as PS.

1. can i now delete all the xmps, if im only working in LR?

2. do i have to keep them for PS or can they be recreated?

3. can other programs, like aperture, capture one or NX use those xmps ?
thanks for clarifying
stephan
Logged

mac pro 12 gb,eizo241W,LR,nikon,fuji
john beardsworth
Sr. Member
****
Offline Offline

Posts: 2750



WWW
« Reply #1 on: June 11, 2011, 06:37:11 AM »
ReplyReply

The catalogue contains all the references to the originals, all the organisation and adjustment work you've done. The xmp sidecar files do not contain everything - they miss out flags, collections, history steps, virtual copies. They have value if you ever open a raw file directly in another program, and much less so as a secondary form of backup.

1. You can delete them, but why bother?
2. LR can recreate them whenever you want by selecting the images and using Ctrl S (Cmd S if on Mac)
3. Some other programs can read them. Aperture and C1, PhotoMechanic can, but Nikon programs generally fail to do so.

John
« Last Edit: June 11, 2011, 06:48:17 AM by johnbeardy » Logged

Hans Kruse
Sr. Member
****
Offline Offline

Posts: 650



WWW
« Reply #2 on: June 11, 2011, 07:30:12 AM »
ReplyReply

hi there,
i recently posted on the x100 forum what i learned in the LL-LR tutorial, that the xmp files should always stay with the raw files and that they contain all the info LR needs to work with them in terms of adjustments, metadata and so on.
now somebody has pointed out that this is not necessary, that all this info is also stored in the lrcat file and the xmps are only needed for other programms such as PS.

1. can i now delete all the xmps, if im only working in LR?

2. do i have to keep them for PS or can they be recreated?

3. can other programs, like aperture, capture one or NX use those xmps ?
thanks for clarifying
stephan


The Lightrooom database (aka. LR catalog) contain all information about your images that is needed in Lightroom. The xmp sidecar files are only written if you enable them to be written in the catalog settings. xmp files only exist for RAW files and only for the edits on the RAW file itself. Any virtual copies will not get xmp files written. The purpose of the xmp file is to be able to use Bridge in Photoshop or open dirently a file from Photoshop so that ACR can read the xmp file to know about the edits you have done in Lightroom. If you loose your LR catalog (should never happen) and you reimport a folder into Lightroom that contain xmp files, LR will import the settings from the xmp files into the LR database.

The settings in the XMP files can only be used by LR or ACR. They cannot be used by any other RAW converter. Although the xmp files are created in XML format the content for each XML tag is proprietary. Some of the tags are easily understood by others are not. See the attached part of an xmp file opened in a text editor.
« Last Edit: June 11, 2011, 07:31:47 AM by hkruse » Logged

Pages: [1]   Top of Page
Print
Jump to:  

Ad
Ad
Ad