Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
02-12-2020, 11:29 AM   #1
Site Supporter
Site Supporter
Larrymc's Avatar

Join Date: Jun 2014
Location: Mississippi, USA
Posts: 4,411
XMP question

I've been trying to make my Keywording more efficient and useable in a variety of processing programs. Currently my Keywords are written to sidecar XMP files but they are only useable in the processing program I originally wrote the Keywords with. I write my Keywords with Zoner ZPS X and the program has the capability to write to Sidecar XMP files and to embed the Keywords in the Pentax generated DNG file similar to what Adobe does. Is there a downside to embedding Keywords in the DNG rather than writing to Sidecar XMP files? One thing I have noticed is when embedding the Keywords in the DNG file that file is smaller which tells me that the DNG is altered in some ways that might not yield optimal results when processing the DNG.

Any opinions on this would be appreciated.

Larry

02-12-2020, 11:46 AM   #2
Otis Memorial Pentaxian
Loyal Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 40,021
QuoteOriginally posted by Larrymc Quote
Is there a downside to embedding Keywords in the DNG rather than writing to Sidecar XMP files? One thing I have noticed is when embedding the Keywords in the DNG file that file is smaller which tells me that the DNG is altered in some ways that might not yield optimal results when processing the DNG.
I think you have discovered the downside in that the DNG is replaced. I suspect that a comparison with the original EXIF will reveal significant differences from an out-of-camera DNG.


Steve
02-12-2020, 02:13 PM   #3
Site Supporter
Site Supporter
acoufap's Avatar

Join Date: Jan 2011
Location: Munich, Germany
Photos: Gallery | Albums
Posts: 2,645
If you touch the DNG container the data contained within it could be damaged. If the algorithms and the original file are implemented properly there shouldn‘t be a problem and the raw capture data will be ok. But if the file is damaged by the writing of XMP data into the DNG container it‘s good to have a copy of the original DNG file. If you do such things using Exiftool it makes a copy by default to be on the secure side.

What really makes me wonder is that your by additional XMP tags modified DNG container gets smaller. Hm. Unexpected this is. Maybe the result of another implementation of compression algorithm get tighter results? - But I don‘t know if the DNG files is created using compression.

What I like is Capture Ones EIP feature. EIP is a zip-compressed container that‘s used to encapsulate the original file (DNG, PEF or whatever). It leaves the original image file untouched and also contains all metadata you created for the image and all adjustments (they are non-destructive) you made on the original image file. EIP can be created in CO1 sessions. It‘s very useful if you often move one image between different computer systems. Everything is contained in the EIP file so you can continue your work using another CO1 copy - no copies of catalogs needed.
02-13-2020, 03:09 PM   #4
Site Supporter
Site Supporter
Larrymc's Avatar

Join Date: Jun 2014
Location: Mississippi, USA
Posts: 4,411
Original Poster
QuoteOriginally posted by stevebrot Quote
I think you have discovered the downside in that the DNG is replaced. I suspect that a comparison with the original EXIF will reveal significant differences from an out-of-camera DNG.


Steve
I wonder how Lightroom affects a DNG as it writes XMP to the DNG also. I suspect the results will be close to what I discovered here. Since I don't have nor use Lightroom I'll just have to wonder. I do know that I won't be saving the XMP data to the DNG but will continue to use the Sidecar as an XMP container.

Larry

02-13-2020, 11:19 PM   #5
Otis Memorial Pentaxian
Loyal Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 40,021
QuoteOriginally posted by Larrymc Quote
I wonder how Lightroom affects a DNG as it writes XMP to the DNG also.
XMP is only written to the DNG if you specifically request the write or are configured to do this as part of normal operation. Default is to have XMP in the catalog alone.


Steve
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
dng, files, keywords, photography, photoshop, program, xmp
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
New confusion with XMP files being "sidecar" with saved JPEG's jpzk Digital Processing, Software, and Printing 9 06-08-2016 09:42 AM
Lightroom DNG and XMP...confused..... raider Digital Processing, Software, and Printing 7 09-03-2013 11:33 PM
Lightroom do not create XMP files Laprou Digital Processing, Software, and Printing 15 03-08-2013 10:45 AM
.xmp files? Kingaircj Digital Processing, Software, and Printing 3 10-11-2010 01:37 PM
Elements XMP files?? OrenMc Digital Processing, Software, and Printing 10 12-03-2008 09:27 PM



All times are GMT -7. The time now is 07:36 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top