# Importing in DNG versus RAW?



## jwbryson1 (Jan 10, 2012)

So I'm reading this book by Scott Kelby and he discusses importing photos into LR3 in DNG format versus RAW.  I've only just begun to read his book but so far it seems pretty good.  :thumbup:

Amazon.com: The Adobe Photoshop Lightroom 3 Book for Digital Photographers (Voices That Matter) (9780321700919): Scott Kelby: Books

My limited understanding of DNG at this point is that it's really the same thing as the RAW file in terms of the ability to process the file, etc., and that the only difference between DNG and RAW is that the DNG file does not contain the metadata (does that mean the EXIF data?) information so you have a file that's about 15-20% smaller than the RAW file which saves space.  Do I have that correct?  :scratch:

One thing that has frustrated me in the past is not dating photos of my kids so I can tell exactly how old my child is in the photo.   However, I now think the EXIF data is included on all photos, even those shot directly to JPEG, so if I have an EXIF reader, I can always go back and get that information.   Is that also true?  

  I don't want to switch to DNG imports and then lose the ability to go back and view the EXIF information to get the date of the photo.

Can somebody clear this up for me?

Thanks.


----------



## 480sparky (Jan 10, 2012)

If you have an issue using .DNG, then why bother?  Stay with your native raw format and carry on.


----------



## jwbryson1 (Jan 10, 2012)

480sparky said:


> If you have an issue using .DNG, then why bother?



I'm just trying to understand how the .DNG format works.  If it can really save me 15-20% of my external hard drive space that the full RAW file would otherwise absorb, why NOT switch to .DNG?  The "why not" would be for the reasons I suggested in my original post and that is would I lose any EXIF information by importing in .DNG?

Anybody else want to try?

Thanks.


----------



## mwcfarms (Jan 10, 2012)

The difference is the XMP sidecare files. If you are giving out work etc its my understand that you need to put the two together. Someone with more experience please chime in here.


----------



## 480sparky (Jan 10, 2012)

All the different manufacturers use a different raw format.  Even within a single manufacturer, different camera models use different raw formats.  A raw image taken with a Canon will not display on the monitor when the the card is inserted into a Nikon body.

My understanding of .DNG is it's Adobe's offering to the digital imaging community.... the photographic equivalent of their .PDF format.  Adobe basically said, "Listen, everyone.  Since y'all can't come to an agreement about a 'universal' raw format, here......... use this one.  It's on the house!"

I wasn't aware that .DNG format didn't allow for exif/metadata recording.  If that's the case, I'll never use it.

Some have commented that all our .NEFs, .CR2s, .SRWs, .RW2s and .CRWs and whatnot will somehow cease to function if .DNG becomes universally accepted.   They may become 'obsolete', but I'll still have half a dozen computers with a couple dozen programs each that will still recognize them.


----------



## jwbryson1 (Jan 10, 2012)

480sparky said:


> My understanding of .DNG is it's Adobe's offering to the digital imaging community.... the photographic equivalent of their .PDF format.  Adobe basically said, "Listen, everyone.  Since y'all can't come to an agreement about a 'universal' raw format, here......... use this one.  It's on the house!"



Got it.  That makes a lot of sense.



480sparky said:


> I wasn't aware that .DNG format didn't allow for exif/metadata recording.  If that's the case, I'll never use it.



Exactly my point.  What mwcfarms said is correct.  What I need to "beef up" on is my understanding of how the .DNG affects the EXIF data, if at all.  If it affects that data then I agree--it makes more sense to stick with the RAW format and to hell with the lost hard drive space.

Thanks for the posts.  :thumbup:


----------



## Big Mike (Jan 10, 2012)

I've moved this out of the lighting & hardware section.  

The big difference is that DNG is an open source format.  This means that anyone (camera companies) are free to use that format if they wish...and Adobe (along with many others) very much hope that the big camera companies jump on board.  But so far, only a couple of them have (not Canon or Nikon).  

The issue at hand is compatibility.  Let's imagine an example.  Say you have tens of thousands of Canon CR2 (or Nikon NEF) Raw files in your archive.  Then in say, 5 or 10 years, Canon decides that they want to use a different RAW format, or maybe they go our of business.  So you live your life, you update your computer and your programs etc.  Of course, you keep your archive of Raw Photos.  So then you go to open some of your photos, but since they are a Canon proprietary CR2 file...you need special software to open them.  If Canon is out of business and Adobe stopped supporting them, then you wouldn't be able to open them (with modern software) and your photos would be lost.

Of course, that is a rather unlikely scenario, but the point is that if your archive is a proprietary file type, you are subject to what that company does.  

But if you use an open source file type, it's much more likely that your archive will be future proof.  

That's the issue.


----------



## 480sparky (Jan 10, 2012)

Big Mike said:


> ........  Then in say, 5 or 10 years, Canon decides that they want to use a different RAW format, or maybe they go our of business. ..........



So let's imagine Nikon goes belly-up.  My computers still work.  The software still works.  I can still manage, edit, save, print, etc.  Nikon's filing for Chapter 11 protection affects my computers not.

Plus, given the absolute proliferation of native .NEFs and .CRWs/.CR2s, even if both of The Big Two close shop, you can bet your sweet bippy there's plenty of programmers out there ready to capitalize on the market.

Long story short....... I'm sticking with .NEF and I still sleep well.


----------



## mwcfarms (Jan 10, 2012)

DNG are smaller and like Mike said its an open format, I know to attach the XMP sidecar you just press command S and it puts it into one DNG file. While Raw photos have a separate sidecar anyways and if you want to include the metadata and edits you have to give them the two files which holds the metadata and edit info anyways. Thats the huge draw or advantage of DNG. Got this all from my Lightroom book.


----------



## Rephargotohp (Jan 10, 2012)

As Far as the Metadata goes, DNG's Embed the XMP file, where as other RAW files either have it as a separate XMP file or as part of the Lightroom Catalog

When you open a RAW file in Lightroom and make any changes to it, whether that is develop changes or changes to Keywords or your metadata template, Those changes are normally only written to the LR Catalog for it's use. However when you take that RAW file out to another program, Those changes do not follow along because that information stays in LR's Catalog only. BUT if you change your Catalog Settings to also write to XMP. Othere programs that recognize XMP files, like Photoshop will see all the changes you made in LR and Vice Versa. 

The problem is, you have to keep the RAW file and the XMP file together in the same folder, or you need to send both if you are sending a file for someone else to use and want to keep your metedata intact.

DBG solves this by embedding the XMP file within it;s structure and also embed a Preview file of the size of your chosing that is updated with the embedded metadata ( in other-words the preview looks like the raw which is not always the case)

DNG's have a smaller file size because they use a different compression scheme than regular RAW files do.

That's said, I don't use DNG's but a lot of my friends do successfully


----------



## mwcfarms (Jan 10, 2012)

Rephargotohp said:


> As Far as the Metadata goes, DNG's Embed the XMP file, where as other RAW files either have it as a seperate XMP fiile or as part of the Lightroom  Catalog
> 
> When you open a RAW file in Lightroom and make any changes to it, whether that is develop changes or changes to Keywords or your metadata template, Those changes are normally only written to the LR Catalog for it's use. However when you take that RAW file out to another program, Those changes donot follow along because that information stays in LR's Catalog only. BUT if you change your Catalog Settings to also write to XMP. Othere programs that recognize XMP files, like Photoshop will see all the changes you made in LR and Vice Versa.
> 
> ...



If you change your catalog settings to also write to XMP it does slow Lightroom down quite a bit though. I used to import Raw but now use DNG because of this reason and I have found it goes a bit smoother.


----------



## Rephargotohp (Jan 10, 2012)

Yes, in LR you can hit Crtl/CMD s to add metadata to the XMP, or you can also set your Catalog to write to XMP under Edit>catalog settings


----------



## Rephargotohp (Jan 10, 2012)

mwcfarms said:


> Rephargotohp said:
> 
> 
> > As Far as the Metadata goes, DNG's Embed the XMP file, where as other RAW files either have it as a seperate XMP fiile or as part of the Lightroom Catalog
> ...



Could be, I've always had it set that way so never noticed the difference in Speed


----------



## Rephargotohp (Jan 10, 2012)

As far as Time and Date and Camera EXIF, That is written to the file by the camera so it would stay with the image. It just things that are later written to the Metadata that may or may not be lost without the LR Catalog, XMP or DNG


----------



## Big Mike (Jan 10, 2012)

480sparky said:


> Big Mike said:
> 
> 
> > ........  Then in say, 5 or 10 years, Canon decides that they want to use a different RAW format, or maybe they go our of business. ..........
> ...


Of course, if you still keep the software on your computer, you're still good.  But it's also possible that if Nikon disappears, they won't release any new software...and the operating system on the computer that you have, in say 30 years, may not run software that was made in 2012.

Like I said, it's highly unlikely but think about how many computer hardware devices are obsolete, not because they don't work, but because they don't have drivers that will work with any operating system made in the last 10 years.  

I don't use DNG either...I'm just bringing up the point of why it exists and is somewhat popular.


----------



## 480sparky (Jan 10, 2012)

Mike:  The simple fact of the matter is: The future is unpredictable.  But even given the immense popularity of digital, film hasn't gone away.  Yes, some _parts _of it has (RIP, Kodachrome!), and Kodak is currently on shaky financial footings.

I can't guarantee that my current computers will still be working in 2042.  But there's nothing to say that .DNG won't be obsolete in 2 years either.

Still, there will be a market for file conversion in 2042 if all the current formats get flushed down the toilet by their various originators.  

Of course, I could be like Eric Cartman.... freeze myself to be thawed out 3 weeks in the future just so I can play on the soon-to-be-released Wii (Season 10, Episode 12).  I'd end up in 2546.


----------



## MTVision (Jan 10, 2012)

DNG doesn't throw out the exif data. I think it might throw out the proprietary information - not 100% sure though.


----------



## Rephargotohp (Jan 10, 2012)

It stores XMP, EXIF and IPTC and can also store Private Metadata ( exclusive to manufacturers) AND it can also ( If you choose) store the original RAW file for later extraction. But at doubling of the file size


----------



## jwbryson1 (Jan 10, 2012)

MTVision said:


> DNG doesn't throw out the exif data. I think it might throw out the proprietary information - not 100% sure though.



This is the key question I was trying to resolve.  Thanks for the post!  :hug::


----------

