Adobe Photoshop Lightroom 4 supports new lenses compared to earlier versions. I was hoping that it would change some of my lenses from 'Unknown Lens' to a specific model, but it did not. Synchronizing my whole collection with Scan for metadata changes does nothing either.

Is there a way to tell Lightroom to rebuild its lens database without removing and reimporting all the images AND without modifying my originals?

While on the topic of lens meta, is there a way to add my own recognition and correct errors? I have one lens which incorrectly shows up, one lens that is only recognized part of the time and one that was recognized exactly once. None of these images have EVER been edited or modified by any software. The directories are on a read-only file-system to avoid all accidental changes.

  • \$\begingroup\$ Unfortunately Lightroom 4 does nothing to correct incorrectly detected lens metadata, even with Synchronize Folder -> Check For Metadata changes. \$\endgroup\$
    – Itai
    Commented Apr 27, 2012 at 16:42
  • \$\begingroup\$ I haven't tried it so won't offer it as an official answer: will LensTagger help? essl.de/wp/2012/05/07/adding-foreign-lens-info-in-lightroom \$\endgroup\$ Commented May 14, 2012 at 12:31
  • \$\begingroup\$ @DanWolfgang - Unfortunately, this one modifies original images which is bad and my system is even setup to make this impossible. Original files are sacred in Non-Destructive workflow! \$\endgroup\$
    – Itai
    Commented May 15, 2012 at 3:07

3 Answers 3


Without rebuilding your catalog or making your files writable, your options seem quite limited. One workaround I thought of was to just create custom lens profiles for the three problematic lenses using the Adobe Lens Profile Creator.

  • \$\begingroup\$ What an interesting suggestion! I will investigate. It actually opens up the question of how does one specify what lens a lens profile applies to? If it is by EXIF lens identifier then it may just work but if it uses the lens metadata in the LR database, the it won't know to apply itself to which unknown lens. \$\endgroup\$
    – Itai
    Commented Apr 27, 2012 at 19:39
  • \$\begingroup\$ I'm not sure by what means LR decides on lens profiles. I would assume EXIF data. My thought was to just manually override whatever LR decides with a custom profile (even if that lens is supposed to be in LRs database). It's a hack, but it just might work for you. \$\endgroup\$
    – user9509
    Commented Apr 27, 2012 at 19:49
  • \$\begingroup\$ Just finished checking. The lens profile is an XML file and it matches a lens automatically by LensID which is specified in the LCP file and must match exactly what is in the EXIF. So the good news is that if I create a lens profile with the right LensID, the right profile will be automatically selected. The bad news is that this does not affects at all what LR reports as the lens in the metadata, so having correct lens profiles will not allow me to filter images by those lenses which are not correctly recognized. \$\endgroup\$
    – Itai
    Commented Apr 27, 2012 at 20:03
  • \$\begingroup\$ Interesting. Are any of these JPEGs by chance? It would be interesting to check the raw EXIF data and also test this on another machine running LR4. \$\endgroup\$
    – user9509
    Commented Apr 28, 2012 at 0:49

Lightroom wizard Godfrey DiGiorgi posted this to the Pentax-Discuss Mail List today, in response to the same issue. I have not tried it myself.

  1. Select "All Photographs" in the Library module, Catalog panel
  2. Set Grid view
  3. Use the filter bar, Metadata switch, set the first column to "Lens", and click on "Unknown"
  4. Select all
  5. Use the "Metadata->Save metadata to file..." command to write out all keywords and other IPTC metadata to the file system for this set of files
  6. Use the "Metadata->Read metadata from file..." command to refresh all the metadata for this set of files
  • \$\begingroup\$ Ouch! I'm hoping that there is another way since I wont accept to overwrite my files. My system is made to be highly organized even outside of LR and searching using the file-system by date would be compromised as well as years of backups which would no longer match. \$\endgroup\$
    – Itai
    Commented Apr 28, 2011 at 3:32
  • \$\begingroup\$ @Itai it would be possible to reset the file dates to be based on shooting date, if it did change them (Personally, I use the "Picture Taken On" column if I'm outside of Lightroom) \$\endgroup\$ Commented Apr 28, 2011 at 7:50
  • \$\begingroup\$ I didn't realize this touched the image files. Are you positive? I'm not that knowledgeable about Lightroom, but I thought it was writing the catalog metadata to some standalone file, then reading that file back in to trick LR into re-scanning the image files. \$\endgroup\$
    – coneslayer
    Commented Apr 28, 2011 at 10:09
  • \$\begingroup\$ @Rowland - Even on an OS that shows that. It is not very practical to use columns that require opening files to show up, particularly when operating an huge directory trees. The Last Modification Data only requires reading the directory structure on most file systems. \$\endgroup\$
    – Itai
    Commented Apr 28, 2011 at 12:34
  • 3
    \$\begingroup\$ This overwrites original files. I checked it and since my FS is read-only got an error 'Lightroom Cannot Write Metadata: Reload from File?' Turns out accepting to reload from file does half the job an recognizes the unknown lens, however it removes all keywords and ratings :( Needless to say, this is not a solution either. \$\endgroup\$
    – Itai
    Commented Apr 28, 2011 at 12:50

I'm suspicious that what you're asking about isn't possible/isn't what you expect.

The metadata is populated from the EXIF stored with the image. If the camera doesn't know what kind of lens is attached it'll report "Unknown." I also had a cheap point-n-shoot that reported no lens meta, even though it was written right on the front of the lens.

The new lenses that LR4 supports are for correcting distortion, and don't have anything to do with the meta in the image, except that it can be used to automatically apply the correct lens profile.

  • \$\begingroup\$ Although they are related, lens identification and lens profiles are not the same thing. For ILCs, the EXIF contains information about the lens attached but that information has to be mapped into an actual lens. As Adobe upgrades Lightroom, it adds new mappings, so it can identify more lenses which are often listed in the release notes. The problem is that it does not apply those mappings to metadata it read in previous runs. For example, while it can identify a DA* 55mm F/1.4 now, it could not do so before LR 3.4, so all photos that were taken with that lens prior say unknown lens. \$\endgroup\$
    – Itai
    Commented Apr 27, 2012 at 19:36
  • \$\begingroup\$ Just to be clear. In the case I am discussing, the camera knows which lens is attached. It is just LR which did not recognize it at the time the image was imported. \$\endgroup\$
    – Itai
    Commented Apr 27, 2012 at 19:40
  • 1
    \$\begingroup\$ Hmm. Doing some investigation, you're right. I've got a handful of Unknown photos that I know are known. \$\endgroup\$ Commented Apr 28, 2012 at 11:55

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.