DNG Files Again

[travismcgee]

<p>I'm thinking about converting my CR2 files to DNG files so I did some research on the Internet and it seems like a lot more people are recommending it now than in the past. Is it catching on? Has it become a more accepted standard?</p>

<p>The last time I saw it discussed here on photo.net, most of you folks said you didn't make the conversion for various reasons. Do you still feel that way? Personally, I see some real advantages for my workflow but I'm wondering what you think. Many thanks and Happy Holidays!</p>

<p> </p>

[EricM]

<p>Yes, I still feel that it's a waste of time and hard drive space duplicating my raw files. Are you able to provide links please, Dave? I'd like to know where "on the Internet and it seems like a lot more people are recommending it now than in the past." as empirical knowledge is the opposite for me. I seem to be the last one in the crowd, but have recently stopped converting almost a year ago. Cheers.</p>

[lex_jenkins]

<p>It's probably best to keep your original raw files as well, unless you're absolutely certain you'll never submit a photo to a contest, news source or stock agency that might require the raw file to ensure no alterations were made that were contrary to their standards.</p>

[Brad_]

>>> The last time I saw it discussed here on photo.net, most of you folks said you didn't make the conversion for various reasons. Do you still feel that way?

 

Yes. Haven't found a compelling reason yet...

[travismcgee]

<p>Thanks, guys. I did some experimenting on my own and decided to stay with CR2, but here are those links Eric asked for. Cheers.</p>

<p><a href="http://photographyconcentrate.com/should-you-convert-dng/">http://photographyconcentrate.com/should-you-convert-dng/</a></p>

<p><a href="http://davidnaylor.org/blog/2010/06/converting-to-dng/">http://davidnaylor.org/blog/2010/06/converting-to-dng/</a></p>

<p><a href="http://lightroomkillertips.com/2010/to-dng-or-not-to-dng/">http://lightroomkillertips.com/2010/to-dng-or-not-to-dng/</a></p>

[Dieter Schaefer]

<p>Not seeing any reason to convert the NEF files into DNG - why would I throw away the original information? The RAW information contained in a NEF or CR2 and most of the EXIF information will always be readable - the codes have already been written - there is no need to the scare tactics that files won't be readable in 40 years (at least the same information that can be extracted now will be extractable in 40 years). Not openly readable currently are the maker-specific information - so I will wait until Nikon and Canon adopt a DNG-type container for their RAW data and provide the keys to the proprietary portion of their NEF and CR2 containers; then I will convert to that format, knowing that all information from the old NEF and CR2 files has been utilized. Currently, this isn't the case and in converting to DNG, information is irretrievably lost.</p>

<p>IMO, a more likely scenario for the future is that Nikon and Canon rather than adopting an adobe-initiated DNG RAW standard, both companies will forgo their own processing software and provide all information to third party software companies like adobe. Or provide their own "plugins" akin to ACR but with the full proprietary information utilized.</p>

[harry_spooner]

Hi Dave,

While I don't shoot canon, I shoot a lot of sports with Nikon, always in raw. My compelling need was that my new D4 was not supported in

CS4, and the MAC version of CS5 (64bit mode) which does support the d4 raw file, does not support the indispensable noise ninja plugin.

Converting the files allows me the flexibility to use CS4 until Jim C. and the rest of the good folks at picturecode can complete the new

64bit plugin for the Mac.

Harry

[john_markanich]

<p>My workflow. I don't shoot many commercial jobs anymore so this approach may/may not be of use to you. <br>

I always shoot RAW+JPEG. The JPEG serves as a 1st defense against obsolescence albeit in an inferior format. The best shots of a given shoot are copied to their own folders. These are duped as DNG files. The RAW file still exists right next to the DNG file in the same folder. This same folder will subsequently contain all the saved steps in my post-processing activities including all iterations of any purpose-modified files. Everything in one place. <br>

This saves me the storage space and the processing time of converting an entire shoot from RAW to DNG. After all, 99.9% of a shoot is chaff anyway. Neither myself or history needs to see my chaff. My intention is to display to the future my finished "Work". Not give them a wheelbarrow full of images.<br>

The whole mess is routinely backed-up to a Dual-1TP external Raid-1 array and another separate 1TP external drive kept off-site.<br>

The prints I make of my best efforts, of course, just like the old days, will only last as long as the ink and paper they're printed on. That's why the Egyptians carved things in stone I suppose. <br>

They made the Pyramids and somehow I don't feel as important.</p>

 

[digitaldog]

<blockquote>

<p>The last time I saw it discussed here on photo.net, most of you folks said you didn't make the conversion for various reasons.</p>

</blockquote>

<p>As the DNG spec continues to evolve, even more reasons to convert. You may have seen the list of advantages to DNG in this older article: <br>

http://www.ppmag.com/reviews/200709_adobedng.pdf<br>

We now have the ability to embed multiple DNG Profiles into the container which is quite useful. The new Fast Load preview options greatly speed up viewing the higher rez preview data in Adobe raw converters or other converters that follow the new spec. You can then turn off the ACR rolling cache (more files that are separate from the original data and limited in numbers stored). <br>

There's a new Losselss DNG option to greatly reduce the size of images that you may be on the fence about keeping or tossing. This is no longer true raw data (it is partially processed) but much smaller in size. I don't use it but could see how say a wedding photographer might take all DNG's now used for a sale and converting to lossless DNG to save space for archive. There are still significant processing advantages of using a Lossless DNG over a rendered image (White Balance is an example). </p>

<p>There's really only two real disadvantages:<br>

1. You intent to use the proprietary metadata <strong>only</strong> the manufacturer's raw converter can understand (Picture styles as an example) that all other converters <strong>don't</strong> understand (the reason proprietary metadata is proprietary!). You can save off the proprietary raw if you think you'll ever use the original manufacture’s converter (I'd never embed it into the DNG). <br>

2. Since any edit you make to a DNG, even tiny metadata changes are saved into the DNG, the entire document gets backed up. That can take more time when backing up (especially to the cloud). Another reason not to embed the original proprietary raw into a DNG. <br>

You will see in the near future another real plus in using DNGs but that will have to wait for description until NDAs are up. Bottom line is the DNG spec, fully documented and free, continues to improve with features that make it far more useful to those who have no need to use the manufacturer's proprietary raw format. </p>

[EricM]

<p>Dave, sorry I forgot about this post. Thanks for those links. The first link you provided is valuable as it is mostly filled with wise comments from experienced photographers and most of which that have either stopped or never bothered to do dng. I wouldn't base your decision from blog authors so much as I've found many just parrot words in the hopes of gaining page clicks. Instead, find users, find photographers, and ask them like you have done here. I enjoy Flickr and Google +. These to me, are the two strongest photo communities going. G+ is my fave and here's a link to the 11,000 member Google + "Photoshop and Lightroom Users" community. I hope it helps, there's some great stuff here. https://plus.google.com/u/0/communities/114820003632329669921</p>

<p>What always caused me anxiety when converting to dng, was that the second you convert, you throw away valuable proprietary data that you possibly can't know that you might want later down the road. Or use it for other software choices. With a DNG, you can't use Nikons Nx2, Canon's DPP, or other great third party converters like DxO and AfterShot and many more; even today you have less choices. Are you 100% certain you will be paying large amounts of money to Adobe and using their products for ever and ever? Probably not.</p>

[travismcgee]

<p><em>The new Fast Load preview options greatly speed up viewing the higher rez preview data in Adobe raw converters or other converters that follow the new spec.</em></p>

<p>Have you really seen that? The speed increase is what intrigued me the most, but I did some tests on my computer and didn't see any increase at all.</p>

[digitaldog]

<blockquote>

<p>Have you really seen that?</p>

</blockquote>

<p>Very much so! On a 5DMII capture (CR2), it takes about 5 seconds to load at 100% (1:1) in Develop and about 2.5 seconds with the same image converted to DNG with Fast Edit option used. The original CR2 is 31.4 mb in size, the DNG 27.5mb in size. Smaller doc, faster loading no ACR cache file needed. etc. <br /></p>

 

[digitaldog]

<blockquote>

<p>...the second you convert, you throw away valuable proprietary data that you possibly can't know that you might want later down the road. Or use it for other software choices.</p>

</blockquote>

<p>Not if it really is proprietary. Proprietary metadata, which may well indeed be written into the DNG is only understood by the camera manufacture or product that wrote it, or it wouldn't be proprietary. <br>

Even if it is understood, as all the Adobe metadata about processing is, every processor will produce a different result because they all have different engines. You can have non proprietary data that says "<em>Saturation Plus 3, Contrast minus 8</em>" but only the converter that <strong>created</strong> this set of instructions treats those instructions as expected. Camera generated White Balance metadata is fully understood but not necessary and often not useful. <br>

All we really need is the raw data. Since only ISO and Exposure affect this, all the other metadata, proprietary or otherwise is only somewhat useful at best. DNG provides us the raw data.</p>

[john_markanich]

<p>Am I missing something here? When I convert a CR2 to a DNG I end up with a CR2 <strong>AND </strong>a DNG file of the same image in the same folder. No anxiety, just redundancy in a different file format.</p>

[EricM]

<p><strong>"Have you really seen that? The speed increase is what intrigued me the most, but I did some tests on my computer and didn't see any increase at all."</strong><br>

<br>

I haven't noticed a speed increase decrease at all between the two. I haven't heard a thing on the forums about this when people argue about it. Maybe dng makes a speed difference on old or weak computer systems, Dave?</p>

[travismcgee]

<p>One of the authors of the one of the articles in the links I provided said the "Fast Load" option really helped. I tried it on my overclocked quad-core machine and didn't see any improvement. Andrew said his 5DIII images take 5 seconds to load in CR2, while my 7D images take only a couple of seconds to load in CR2, so my machine must be okay. Gotta run.</p>

[digitaldog]

<p>The machine I tested this on is an 2.66 GHz Core i7 with 8 gigs of ram.</p>

<p>You have to first load a CR2 or proprietary raw into Develop <strong>for the first time at 1:1</strong> and time it (after which it will show full rez faster because the ACR cache file was built and is now used). You then have to convert a copy to DNG with fast load and again time it in Develop. As illustrated, on a 5DMII, the differences is almost twice as fast with the DNG. The DNG is still smaller than the CR2 despite the pre-processed data and all the other possible inclusion of this container. The ACR cache is a rolling cache so at some point, you'll lose the pre-built preview data. The ACR cache files would have to travel to all other drives you hope to use the proprietary raws IF you want the increase in preview loading. Otherwise on another drive, it will be rebuilt. Not the case with the DNG, the preview data travels with the DNG of course. </p>

[EricM]

<p>It's no speed increase when you take into account the time needed for the conversion process in the first place. Converting to dng (on import) is a time hindrance. Then I have to back up both native raw and dng. The dng conversion process does not speed up anyones workflow in the least. I haven't noticed an increase in previews when at 1:1 on a 27" monitor and running 24" as a second monitor. I've recently asked at least a dozen working commercial photogs that I know personally and none of them bother with dng either. I see no compelling reason to return to dng converting and is a relief that I have less files to back-up and archive.</p>

[digitaldog]

<blockquote>

<p>It's no speed increase when you take into account the time needed for the conversion process in the first place.</p>

</blockquote>

<p> <br>

True IF the only advantages to conversion were the speed increase in viewing 1:1 data in Develop (and you never lost the initial ACR cache which you will or you move images from drive to drive and use them). </p>

<p>Fast Load in <strong>just one more example</strong> of icing on the cake for the use of DNG.</p>

<blockquote>

<p>Converting to dng (on import) is a time hindrance.</p>

</blockquote>

<p>Now if only the stupid camera manufactures would give us, their customers the option of saving proprietary Raw, DNG <strong>and</strong> JPEG, there would be zero speed hit to convert. The camera system would give us this preferred, requested file format just after we snap the shutter. </p>

<blockquote>

<p>The dng conversion process does not speed up <strong>anyones</strong> workflow in the least.</p>

</blockquote>

<p>Speak only for yourself, not the rest of us <strong>please</strong>! It speeds my workflow a great deal. And again, if the camera would give me the data I wished, the entire point of yours would be moot. </p>

<blockquote>

<p> I've recently asked at least a dozen working commercial photogs that I know personally and none of them bother with dng either.</p>

</blockquote>

<p>Which makes those of us who do disagree with you and your buddies. Whats your point? I should alter my preferred workflow based on your preferences? Not going to happen. </p>

<blockquote>

<p>I see no compelling reason to return to dng converting</p>

</blockquote>

<p>Then don't. </p>

[DawsonPointers]

<p>Converting to DNG is part of the process for importing into Lightroom for me. I did it to get rid of the sidecar edit files seen in Bridge, etc. I have found no disadvantage. At first I was concerned about loss of 'something'; but, after doing it for more than a year, nothing has gone wrong yet.</p>

[travismcgee]

<p>Sidecar files are annoying, so I don't use them, even with CR2s.</p>

<p>That's interesting about the ACR cache. I think I'll move it to an SSD drive when I get home. I might get a speed increase from that.</p>

<p>What is the deal with competitions and journalism accepting DNGs that Lex mentioned? I'd hate to convert my photo of a Bigfoot to DNG and have nobody believe me.</p>

<p> </p>

[lex_jenkins]

<blockquote>

<p>"What is the deal with competitions and journalism accepting DNGs that Lex mentioned?"</p>

</blockquote>

<p>Wording varies among organizations but here's an example of the rules for the <a href="http://submit.worldpressphoto.org/">World Press Photo annual contest</a>:</p>

<blockquote>

<p><strong>"</strong>The content of the image must not be altered. Only retouching which conforms to currently accepted standards in the industry is allowed. The jury is the ultimate arbiter of these standards and may at its discretion request the original, unretouched file as recorded by the camera or an untoned scan of the negative or slide."</p>

</blockquote>

<p>The phrase "as recorded by the camera" seems to imply that provenance is determined from the original camera raw, JPEG, TIFF or other file format as designed by the camera manufacturer. Ricoh uses DNG for the camera raw in recent models. Presumably that would be acceptable, whereas a Nikon NEF converted to DNG might not meet the WPP standards.</p>

<p>I haven't read enough recent articles on journalism industry sites to know for certain whether this specific provenance test has been applied.</p>

<p>As far as I know, Leonard Nimoy remains the authority on determining the authenticity of Bigfoot photos.</p>

[digitaldog]

<blockquote>

<p>The phrase "as recorded by the camera" seems to imply that provenance is determined from the original camera raw, JPEG, TIFF or other file format as designed by the camera manufacturer.</p>

</blockquote>

<p> <br>

And a DNG contains raw data so I don't see how this would be a factor at all. I have to wonder if this would even be an issue in court (depending on the country, the court system etc). It would be very difficult to suggest that the raw data from the proprietary raw is somehow less useful as a truth indicator than the original proprietary raw. But short of a legal issue with images, I'd simply ignore the comment as anyone who wouldn't accept a DNG (and why would you send a un-rendered neg?) is making a mountain out of a molehill. <br>

<br>

IF I retouch an image to show Big Foot, make a print and shoot that with my Canon, is the image any more truthful if I select raw or JPEG or convert to DNG? This is a anti-DNG rabbit hole that has no merit, let it go. </p>

[richard__]

<blockquote>

<p>The phrase "as recorded by the camera" seems to imply that provenance is determined from the original camera raw, JPEG, TIFF or other file format as designed by the camera manufacturer.</p>

</blockquote>

<p>This is the primary reason I am attempting to move to DNG, although using that outside of the Adobe workflow is going to be a problem for me. By leaving the original RAW file untouched, it then is available as a backup, and for those times when it may be required.<br /><br />I <a href="http://www.henleygraphics.com/MetaMFix.htm">revise</a> the Nikon shooting data for each old non-cpu lens, which are always recorded by my digital camera as having a Lens Max Aperture value of f/1.0 (other Nikon camera's may place a f/0.0 value there). Despite the fact the proper lens data is correctly entered into the camera's non-cpu lens data table, which the camera uses for exposure calculations.<br /><br />When I complained to Nikon about this I was told that this was a feature (request) and not a bug.<br /><br />In order to correctly identify the lenses, I need to edit the Lens Max Aperture metadata for my raw files right off before importing them into Lightroom, so I do this to the DNG file and leave the original NEF files untouched from their original state.</p>

[lex_jenkins]

<p>Andrew, I'd tend to agree with you. But it's uncertain whether the folks who set the standards for photojournalism and rules for contests would agree that, say, a Nikon NEF converted to DNG would pass muster if the judges or arbiters insisted on examining the original, unretouched file as recorded by the camera.</p>

<p>It's likely the juries for these contests have discussed this issue and may indeed accept DNGs converted from original proprietary camera raw. I just haven't had time to read all the available rules and FAQs to get a sense of where that wind is blowing this year.</p>