DNG vs RAW

[raindog se]

Hey

Right now I am converting all my RAW-files (crw, cr2) to DNG-files... and I wonder what reason I might have to keep the RAW-files?

I intend to use the DNG-files in my workflow and keep a backup of them.

I like the fact that DNG-files don't have any loose XMP-files and that they tend to be smaller in size.

So, will I ever need my original crw and cr2 files?

Regards
Jonas

 

[Richard Weisgrau]

Probably not. Adobe will support DNG forever, but as the volume of RAW formats increases it is possible that they will eventually drop some RAW file processors from support as years go by.
--
Richard Weisgrau
http://www.weisgrau.com
Author of
The Real Business of Photography
The Photographer's Guide to Negotiating
Selling Your Photography
Licensing Photography

 

[Gale Bizet]

Who knows what software will do in the future.
Always keep your original raw files....
Play with others all you want
--
Best Regards
Gale

http://www.pbase.com/techwish

 

[ted w dillard]

Your camera's RAW files, and almost every other's, has OEM proprietary data that they reserve for use in their own processors. Although Adobe has allowed for "maker notes" in the DNG, a place in the file where the OEM can put this data, the major OEMs don't use most of it and still keep some data as "secret sauce" unavailable to the DNG conversion.

Why they do this I don't understand. Neither do I understand why the camera manufacturers refuse to add a DNG file shooting option. Again, the OEMs say they need to keep some data proprietary, yet Adobe allows them to do so in the DNG.

Besides that, I just don't like throwing original stuff away, my vote is to keep them all.

--
Ted Dillard
Managing Editor, Head-2-Head Reviews http://www.h2hreviews.com
Smart Object Evangelist and digital photo support- http://www.teddillard.com

 

[Photo_Op8]

Hey

I intend to use the DNG-files in my workflow and keep a backup of them.

Regards
Jonas

Seeing that you're keeping a backup, why not just embed the RAW in the DNG? Belt and suspenders.
--
http://davebhc71.zenfolio.com
Mac Deskpro Intel, OSX 10.6.2, Lightroom v2.6, Sony A700

 

[owenleve]

I import my raw (nef) files into light room. Edit and convert to dng. Not keeping the original raw files. Time will tell if that's a mistake.

If dng is no longer supported it wouldn't happen overnight. It WOULD be a nightmare for myself and many others. Can't imagine having to convert the thousand of dng files to .tiff, psd, etc...

I really wish nikon/canon would embrace the dng format. Or, at very least I wish Nikon would produce software that was 'modern'. Maybe I should give it another go but in the past the nikon software has been awful.
--

http://www.courtlevephoto.com
http://www.courtlevephotography.com

 

[rainierphoto]

I convert all my NEFs to DNG's and chuck the original. Smaller file sizes and no sidecar files are the main reasons. I make several backup copies of all my DNG's as well as backups of them as Tiffs. I suspect that as time goes on DNG will continue to gain support rather than the opposite.

 

[Tom Reynolds]

Hey

I intend to use the DNG-files in my workflow and keep a backup of them.

Regards
Jonas

Seeing that you're keeping a backup, why not just embed the RAW in the DNG? Belt and suspenders.
--
http://davebhc71.zenfolio.com
Mac Deskpro Intel, OSX 10.6.2, Lightroom v2.6, Sony A700

This is what I would recommend for your backup copy. This dng version is larger because it contains the original raw file as well, but there are some very good software programs that do not handle dng files. There could be one in the future that you really like and would like to use. This gives you the option of changing your mind later. The smaller dng version would be the one you edit and keep handy to make prints from, etc.

 

[Barry Pearson]

I suspect that as time goes on DNG will continue to gain support rather than the opposite.

I've been tracking (and publishing) the take-up of DNG since 2005.
Yes - the evidence is a steady increase in DNG support.

Archived product lists for 1st year to 5th year since launch:
http://www.barrypearson.co.uk/articles/dng/products_y1.htm
http://www.barrypearson.co.uk/articles/dng/products_y2.htm
http://www.barrypearson.co.uk/articles/dng/products_y3.htm
http://www.barrypearson.co.uk/articles/dng/products_y4.htm
http://www.barrypearson.co.uk/articles/dng/products_y5.htm

Timeline:
http://en.wikipedia.org/wiki/Digital_negative#Timeline

 

[raindog se]

Hm... some keep and some trash their RAW files, oh what a pickle

I don't fancy the idea of letting the DNG "eat" the RAW... it would give twice as large file sizes to handle.

A question about that... if you extract a RAW file from a DNG will the XMP also be extracted as a sidecar?

Thinking out load... when I work with my DNG's in ACR they save the XMP inside and that is far better than in a sidecar. But if I should loose my DNG file and have to go back to the original the RAW file would lack the XMP info...

Sure, I could archive the RAW's and just work with and backup DNG's. That would, with some extra work and disc space, give me triple files with all possibilities of the future. That sounds pretty okay to me

Thanks for your thoughts!

 

[Richard Katris]

I have noticed a lot more corrupted files as DNG ones than CR2 even though the CR2 are larger. I am going to guess here that the reason for this is that every time we rewrite a DNG file with modifications...it overwrites the existing DNG file and resaves it to disc.

Increased rewriting along with the huge sizes we are now dealing with increases the likelihood of corruption. So....while I DO like the smaller DNG files and might get rid of the CR2 ones...I unlike others think that the maintenance of separate XMP files is a boon rather than a problem because you do not rewrite the raw files constantly as you try different rendering of RAW images.

At present I am still using cs3, and it doesn't support the 7D I am using...so... I convert to DNG, then I make the files "read only". This forces ACR to continue to write XMP files alongside the DNG files instead or rewriting the files constantly. As I never did have a problem with the XMP files, I like this solution.

I am now archiving both the DNG and the cr2 versions and the XMP less often....

As what I shoot ends up largely in stock...access in the future is paramount to my work flow. If I was shooting weddings and handing over files to the client, that would be far less important to me.

--
Richard Katris aka Chanan

 

[Barry Pearson]

I have noticed a lot more corrupted files as DNG ones than CR2 even though the CR2 are larger. I am going to guess here that the reason for this is that every time we rewrite a DNG file with modifications...it overwrites the existing DNG file and resaves it to disc.

If you look inside a DNG file created by Adobe's DNG Converter, the XMP is near the start, with plenty of free space after it. I believe Adobe's software doesn't overwrite the whole file, but just a block or two near the start, when it writes the XMP back.

 

[Tom Marshall]

I have noticed a lot more corrupted files as DNG ones than CR2 even though the CR2 are larger. I am going to guess here that the reason for this is that every time we rewrite a DNG file with modifications...it overwrites the existing DNG file and resaves it to disc.

If you look inside a DNG file created by Adobe's DNG Converter, the XMP is near the start, with plenty of free space after it. I believe Adobe's software doesn't overwrite the whole file, but just a block or two near the start, when it writes the XMP back.

I tend to agree with the notion that multiple writes to a DNG will increase the odds of file corruption.

And while I agree that side-car files are the best solution in terms of non-destructive editing, I'm one of those individuals who loathes all that clutter (and having to remember to keep all the sidecars in the same folder as the original).

So I retain my original RAW files, but create DNG versions which house all my edits.

Does anyone here use Irfanview? I use both Mac and PC, and move files between both OS with an external drive. On the Windows side, Irfanview is a great, low-overhead tool for viewing the embedded jpg in RAW files. I use Photo Mechanic and/or LR for most of my viewing, but sometimes it's easiest just to right-click an image file in Windows Exporer and open it with Irfanview. Irfanview can also handle DNG.

Caveat:

Irfanview has no problem displaying the contents of a DNG when it is initially created from the RAW file. But if you subsequently edit the DNG (ie, in ACR or LR adjust levels, saturation, sharpening, etc.) and then update the DNG with the new edits, Irfanview will choke everytime if you try to open the updated DNG file.

This would seem to indicate that something is not quite right with DNG and the way it retains image edits.

Tom (Marshall) Heim
http://www.pbase.com/t_heim

 

[Richard Katris]

that may be the case...that it only rewrites a portion of the file...but it seems to take a whole lot longer to update the files when you don't make the DNG files "read only" than it does if you use the external XMP files instead of ones that contain the modification data in the DNG.
--
Richard Katris aka Chanan

 

[Tom Reynolds]

A question about that... if you extract a RAW file from a DNG will the XMP also be extracted as a sidecar?

No, just the original raw file pops out. Surprise! I'm Back! But the dng file still has the edits somewhere in it so all is not lost.

I am not an expert on side cars, but one of the problems I have is that most raw conversion programs have their own unique type of side care file. If I use more than one program, or change programs it is too confusing to me. If software vendors all standardized the side car, that would be great - but not likely. Also, making sure I know, or the program knows, where the side car file is, makes me nervous.

 

[calson]

If your camera has special settings that are stored in the RAW files and needed for post processing you will lose this information in the DNG file and might as well store them as compressed TIFF files. DNG is an Adobe format that is not supported by either Nikon or Canon.

For example the Active- D camera settings available with Nikon D300 and D3 cameras is capable of extending the DR by 2 or more stops, the native RAW file data is needed by Nikon's Capture NX software. Convert the RAW to a DNG file and this information is lost.

I have also had standard D3 NEF files that exhibited banding when processed with ACR but were fine when I opened them in NX and then converted to TIFF files and opened them in Photoshop. With DNG the banding would have been present and I would have lost the images.

Doing extra work to convert to DNG really makes no sense at all. If Nikon goes out of business 20 years from now and I still have Adobe Photoshop it will still be able to open the Nikon or my Canon RAW files. DNG makes sense for people shooting with Sony or Panasonic where the RAW formats are much less likely to be supported in the future.

 

[Barry Pearson]

If your camera has special settings that are stored in the RAW files and needed for post processing you will lose this information in the DNG file and might as well store them as compressed TIFF files.

If they are stored as an Exif Makernote they are not lost. And typically this is how the major manufacturers store them. The Makernote is copied to a tag called DNGPrivateData, from which it can be retrieved by any code that chooses to.

Whether specific code chooses to is another matter. In your case, presumably it doesn't.

 

[thesurfdog]

So why not just send all the RAW files to a couple of external drives..? I mean, it's not as if you MUST make a choice between the two. Then if you decide down the road that you need the original data it's all there. If not...well, then you're only out a couple bucks and no harm done.

 

[Tim Palmer]

This is my 20th year shooting digital... I think I have seen every known format there is ;-)

I would recommend you keep the RAW file, one reason (someone else mentioned this) is in a lot of cases the RAW file contains data that only the manufacturers software can see. This is to make their software look better, keeping you close to home. If your workflow is good for you, then great, however if you ever get into a situation where an image was horribly over or under exposed, using the RAW file and proprietary software gives you the best chance to produce a good file.

This is far more common in the medium format world, less in the DSLR's. But storage is cheap... better safe than sorry in my opinon.

 

[raindog se]

I have never used Nikons nor Canons software, I used to use Capture One but now I'm rather happy with ACR.

My first DSLR was the Canon 10D and now I have a 40D and I don't think I ever used any special in camera editing... I might have tested b/w sometime but I have always preferred post processing in C1 or ACR.

New DSLR's have more interesting in camera possibilities so I think you have more reason to keep your originals today than if you have an older model.

The feeling I get from reading yours and others insights is that the absolute majority never had any problems with DNG... but many are concerned with what might happen.
I agree, I feels a bit unsafe/wrong to trash the original RAW-files...
My biggest issue is to maintain a consistent workflow, I don't have that yet

My point is - the less stuff you have the easier it is but that is partly a different story.