NEF and DNG

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I've just converted 390mb of NEFs to 343mb of DNGs to see the difference. That's 344 files. Pity Nikon and all the others don't save straight to DNG like the Pentax does. I do prefer just having the one file on my system rather than the xmp as well. I'm bit of a neat freak!:rolleyes: Plus obviously we could fit more photos on a card.
 
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I expect the reason the file size is smaller is the preview image is lower quality.

I solve the single file issue by using Capture NX2. It puts all its changes into the NEF file.
 
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Two files means you have to copy two files to move them, but two files have other advantages:

1. Edit the NEF, and it saves a 8KB xmp file, instead of rewriting a 10MB file. Fast to edit and save 200 images simultaneously that way. Also this does not change the NEF file date.

2. If you want to revert back to the original unedited version, just delete the xmp file.
 
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Two files means you have to copy two files to move them,

I assume that you mean that you have to select both files to copy or move them. Even so, you only need to select the NEF, not the NEF and the XMP file. An XMP file is called a sidecar file because it remains attached to the image file just as a sidecar remains attached to a motorcycle; whether you copy, move, rename or delete the image file, the same thing automatically happens to the sidecar file.

If you want to revert back to the original unedited version, just delete the xmp file.

If you are storing metadata in the XMP file (as I do), deleting it is very dangerous. If you are using Capture NX2, it provides access to the original, all versions that have been named, and the most recently saved version whether or not it has been named.
 
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If you are storing metadata in the XMP file (as I do), deleting it is very dangerous. If you are using Capture NX2, it provides access to the original, all versions that have been named, and the most recently saved version whether or not it has been named.

That's interesting. If CNX2 sees an xmp file, it uses that information? I don't have xmp files and I get access to the original version, the named versions and the most recent saved versions. CNX2 is saving this within the original NEF file.

Does Windows know to deal with these files in pairs? I know it is able to do so with things like saved web pages (it keeps the images in a paired folder), so the idea isn't foreign to Windows.
 
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My Windows 7 does not know about any xmp files. Xmp will not be copied with NEF (via Windows). However, any user ought to realize that (seems no problem).

Likewise, my D300 camera does not know about xmp files either.

Using Adobe, delete the xmp, and you have left only the original image, same as on the day from the camera.
 
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That's interesting. If CNX2 sees an xmp file, it uses that information?

Now that I have read my post again, I see how I could have confused you. CNX2 doesn't read the metadata that is stored in the XMP file, at least not when it is embedded in it by IDimager when using my system.

Does Windows know to deal with these files in pairs?

My Windows 7 does not know about any xmp files. Xmp will not be copied with NEF (via Windows).

Very interesting! I use Vista and it automatically copies, moves, renames and deletes the XMP file if only the NEF is selected. I can't imagine why Microsoft would have designed Windows 7 NOT to do the same. Apparently an XMP file is a sidecar file in that sense only with certain operating systems.
 
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Very interesting! I use Vista and it automatically copies, moves, renames and deletes the XMP file if only the NEF is selected. I can't imagine why Microsoft would have designed Windows 7 NOT to do the same.


If I use Adobe to copy them (in Windows), Yes, Adobe knows they are sidecars.

Windows Explorer has no clue however. They are both just files.
 
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Now that I have read my post again, I see how I could have confused you. CNX2 doesn't read the metadata that is stored in the XMP file, at least not when it is embedded in it by IDimager when using my system.

With your explanation, I am now able to read your previous comments the way you meant them.
 
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dangerous?
when you delete them, they are gone.that's it.

Yes, dangerous. When they are deleted the metadata that is stored in them is also deleted. One of the benefits of having that information stored in the sidecar file (or the image file) is that doing so allows me to import that information into the database in the event that everything else that could possibly go wrong does go wrong. I can recreate my entire database by importing the information stored in the sidecar (or image) file. Just a couple of weeks ago, using that process easily and quickly solved a problem for a user whose database and backups had apparently become messed up.
 
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Two files means you have to copy two files to move them, but two files have other advantages:

1. Edit the NEF, and it saves a 8KB xmp file, instead of rewriting a 10MB file. Fast to edit and save 200 images simultaneously that way. Also this does not change the NEF file date.

2. If you want to revert back to the original unedited version, just delete the xmp file.
Good points. hadn't thought of that. Although with DNGs Adobe give the choice of embedding changes or producing sidecars.

If you are storing metadata in the XMP file (as I do), deleting it is very dangerous.
I don't understand this. Isn't the metadata stored in the NEF? Cos that's all I get out of the camera. And yeah, Windows XP here, files is just files, move the NEF and the xmp stays where it is.

Still I think it would be nice to be able to save native DNGs, they're smaller, and you can then choose how the adjustments are saved, embedded or sidecars.

P.S. Glad you guys don't jump down my throat every time I questions stuff I'm used to from my Pentax past!:redface:
 
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Isn't the metadata stored in the NEF?

All metadata created by the camera and I think all metadata created using Transfer, View NX or Capture NX is stored in the NEF. (Someone please correct me on that last point if I'm wrong.)

I use IDimager to change the metadata. IDimager provides the option of storing it in either the NEF or the XMP file. Many people apparently use IDimager to store the metadata in the NEF and I have never heard of anyone experiencing a problem. The reason I store it in the XMP file is that Nikon may some day change the proprietary method of providing content in the NEF. If that happens, storing metadata in the NEF today using non-Nikon software could theoretically cause problems in the future. That is especially true if Nikon makes those changes and does not provide tools to third-party developers that make it possible to deal with the change. Though that eventuality is extremely remote in my mind, it's a situation that I am avoiding by storing the metadata in the XMP file. Better yet, doing so has no undesired consequences (at least not for me). Even so, I always have the option of storing the metadata in the NEF if sometime in the future I determine that doing so becomes preferable.
 
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I love the xmp sidecar files. Since I rarely move images once I've ingested them, having the sidecar file isn't really an issue for me. I put a lot of metadata into all my images and if I make a lot of metadata changes, only the xmp sidecar file has to get sync'd across my backup drives (except for the jpg photos). I recently finished re-doing all the metadata on my whole library going back to 1999.

I didn't know that DNG allowed sidecar files. I may have to look into dng's again.
 
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Working primarily in Lightroom I spend most of my time oblivious to xmp files. Of course I could convert everything to DNG. However as far as being the default digital negative format, until it's adopted by more 3rd parties I'm less comfortable about using it than I am about staying with my Nikon proprietary format and a Lightroom database. I'd love a world where we all used a single open source format for shooting and editing raw files. I applaud Adobe's efforts but we're not there yet by a long way.
 

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