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View Full Version : Benefits and drawbacks of DNG?


StephenL
21st March 2009, 05:42 PM
OK, so I know that DNG has lossless compression, and doesn't use a seperate sidecar file for exif and iptc, but are there any disadvantages to converting my ORF files to DNG as I download them?
Can most RAW converters nowadays handle DNG?
I ask this 'cos I've just started reading Scott Kelby's excellent book on CS4, and conversion to DNG is one thing he recommends.
Previously I've stuck to the proprietry raw formats on the grounds that DNG, although supposedly an open standard, was written by Adobe and therefore not totally unbiased. Or am I just being unduly cynical and there are real benefits and no drawbacks to DNG?

gno
21st March 2009, 09:45 PM
Hi Stephen,

You may be interested in this (http://www.adobeforums.com/webx/.3c05f1f2?14) discussion.

Regards

Gavin

emirpprime
21st March 2009, 10:04 PM
I have no real advice/info other than that I have been converting to DNG for a long time now and have found no negatives. I do have a Lightroom and PS workflow so have no issues with incompatibilities, but have found almost off of the better known programs support them. The big benefit as I see them is that is drops the file size considerably, and the perception that it is more "future-proof".
All the best,
Phil

250swb
21st March 2009, 11:00 PM
Unless you are working with software programmes that do not support .ORF files I can't really see the point in converting to .DNG before you process them. You simply end up with an .ORF file AND a .DNG file, both indentical in image content, and you either process one or the other.....

The logic of saving as a .DNG file because it is smaller that a .ORF file escapes me, given you have both on your hard drive and the .DNG is therefore adding to the storage, not reducing it. I mean, you wouldn't consider deleting the original .ORF would you? And also consider that 750gb of hard drive is only around 80, that is about 15,000 full size .TIFF files, never mind 83,000 .ORF files.

Steve

emirpprime
21st March 2009, 11:48 PM
Yes I do delete the ORF... RAW is RAW, so the file is still the original, providing you trust the ability of the converter to recompress the data.
It all depends on your needs. I shoot, download to laptop and store working projects, archive to a server and backup to an external drive. The laptop is a serious space contraint when a single shoot often starts with ~300 photos. Then start editing. The print ready conversion, client previews etc etc. It soon adds up.

I wouldn't saw it is right for everyone, or that there is a right answer. But if the shoe fits...
P

StephenL
22nd March 2009, 07:45 AM
Space isn't a constraint for me - I have 2Tb in my machine and 1.5Tb of external storage. And yes, if I moved to DNG I would delete the ORF files. I see getting rid of the sidecar files as being a major advantage, as so often when you move files without using a "clever" program such as Lightroom, they can end up separated.
No, my main concern was future compatability. For instance, will by CRW files from my Canon 10D years ago still be able to be opened in the future? And by that token, will DNG files?

StephenL
22nd March 2009, 07:49 AM
Thanks for the link, Gavin. It includes another link, http://www.barrypearson.co.uk/articles/dng/, which needs serious reading!

Hi Stephen,

You may be interested in this (http://www.adobeforums.com/webx/.3c05f1f2?14) discussion.

Regards

Gavin

Wreckdiver
22nd March 2009, 09:04 AM
One of the main benefits for me is future compatability for the photos I already have. Anyone who was using PS CS2 and then bought an E-3 will know that they would have had to upgrade to CS3 to be able to open the .orf files. The last Adobe raw converter for CS2 did not support the E-3.

If the claims that the .dng standard will be "future proof" then any files converted to this standard will always be able to be opened in the future with new software. That is why that from now on I will be archiving a .dng file along with my orfs and tiffs. Storage space isn't an issue these days.

Steve

shenstone
22nd March 2009, 09:26 AM
I think one of the main benefits for me is future compatability for the photos I already have. Anyone who was using PS CS2 and then bought an E-3 will know that they would have had to upgrade to CS3 to be able to open the .orf files. The last Adobe raw converter for CS2 did not support the E-3.


What you're referring to in this is backwards incompatibility which si something that Adobe just don't do, especially with Bridge ( which is one of my gripes about them). Once a new version comes out they will not release compatibility patches for the prior versions.

On the ORF vs DNG aspect the answer is that the DNG can contain a version of the RAW file which for people who are using uncompressed RAW formats can be a space saving boon, but depending on the options you are using then you have to either consider it a "Container" which is I guess what stephen is looking at in terms of not losing sidecar files or a "processed" version in which case you've done what you can in processing and have to live with it.

re Openness... the cynic in me says Adobe still have a lot of caveats in the terms.

IMO there will always be a better ORF to xxx (DNG, JPG etc) processor coming along so until the point that Olympus decide to drop ORF then why not wait and just convert as one huge batch job. By moving to DNG you just make that a DNG to DNG2 job.

Regards
Andy

crimbo
22nd March 2009, 09:52 AM
My main worry about moving to DNG and losing my ORF files is the demosaicing.
Mainly at a pixel peeping level, Olympus files are a little better either with the proprietary Olympus demosaicer or by using the VNG algorithm. Adobe appear to use the AHD algorithm that is less suited to Olympus files - certainly from the E400, IMHO
So I will continue to store away my 20MB raw images

OlyPaul
22nd March 2009, 11:36 AM
I've converted my all my Raw files to DNG from way back to when I used Canon. It's always a personel preference at the end of the day but as I have said before I would put money on Olympus pulling out of the digital slr market before Adobe gives up the software market.
As to Shenstones comment

"re Openness... the cynic in me says Adobe still have a lot of caveats in the terms."

Pehaps he does not know that Adobe own the TIFF format ,and is he going to stop using Tiff because of that! ;)

As to formats Canon now no longer support the D30 in there software and its only a matter of time before other major camera brands start dropping support for there older cameras and even if you keep the old software there is no guarantee it will work with future operating systems.

And as to converting them all to DNG when the Orf's are no longer supported, who is to say Adobe will keep supporting older formats as well, as each raw format even from the same manafacturer and from camera model to camera model is different there is bound to reach a saturation point where it not finanacialy viable to keep supporting them as we have already seen from other software and camera manafactures. But you can guarantee Adobe will support DNG even from old conversions.

If you use Adobe software then you will see absolutley no difference in quality from a orig raw or dng conversion and most other Raw converters like Silkypix support the Adobe DNg format and for me personely the Oly software is a obomination.

As I said its all a matter of preference but with all the above and the extra conviniance of dng in image managment its a no contest for me and especially as I just stared running Lightroom 2 .:)

petrovich
22nd March 2009, 11:46 AM
Is there a raw to dng batch converter out there(Sorry to show my ignorance on this).
I have imported direct to lightroom and saved as raw...
I have also realised that I should spend more time on this and buy a decent Scott K book.

Regards

Jim Ford
22nd March 2009, 02:37 PM
Is there a raw to dng batch converter out there(Sorry to show my ignorance on this).


Yes, 'Adobe DNG Converter':

http://lmgtfy.com/?q=adobe+dng+converter&l=1


I have also realised that I should spend more time on this and buy a decent Scott K book.


The 'Real World Camera Raw' book by the late Bruce Fraser is excellent, as are all his other books.

Jim

OlyPaul
22nd March 2009, 02:48 PM
Is there a raw to dng batch converter out there(Sorry to show my ignorance on this).
I have imported direct to lightroom and saved as raw...
I have also realised that I should spend more time on this and buy a decent Scott K book.

Regards

Peter if you have Lightroom and providing its up to date then you already have the ability to convert to DNG upon download from your memory card.
http://www.pbase.com/paulsilkphotography/image/110484518.jpg

If you want to convert your raw to DNG that are already in Lightroom then you have that ability to do that as well.
http://www.pbase.com/paulsilkphotography/image/110484516.jpg

And if you want the stand alone converter you can get it here.
http://www.adobe.com/support/downloads/product.jsp?product=106&platform=Windows

For a easy to understand and hold you by the hand type of book then Scott Kelby's Lightroom/ Lightroom 2 is hard to beat. :)

shenstone
22nd March 2009, 05:27 PM
As to Shenstones comment

"re Openness... the cynic in me says Adobe still have a lot of caveats in the terms."

Pehaps he does not know that Adobe own the TIFF format ,and is he going to stop using Tiff because of that! ;)


Hi Paul... Yes he does, but there is a difference between using something fully understanding the ownerships and making a decision based on an assumption of openness that may or may not exist in the same way in the future. Tiff is a defacto standdard in large parts of this industry and Adobe are positioning DNG for that in the future, but it's not quite there yet.


And as to converting them all to DNG when the Orf's are no longer supported, who is to say Adobe will keep supporting older formats as well
<snip...>
But you can guarantee Adobe will support DNG even from old conversions.

Sorry to disagree again, but there are no guarantees in this world

In a work context I had to fight with some very old PDF files recently ( I work in an industry where very long record keeping is necessary). Currently Adobe software only supports v3 onwards so we had to do some onwards conversion. I've had similar fun with Oracle databases. You just keep an eye on the versions you have installed and take action before overwriting something that removes such compatibilities

The point I was making was people don't need to feel pushed into DNG now and there are valid reasons for porting only to another file format at the point of need. e.g. DNG being the current flavour, but there may be another along soon - A couple of years ago there was the push on Microsoft HD format that came to not very much http://www.microsoft.com/prophoto/downloads/hdphoto.aspx

Regards
Andy

StephenL
22nd March 2009, 05:48 PM
Andy, thanks for all your comments. Your mindset seems to be working on the same lines as mine (poor you!).
I think the answer is that there is no answer - your suggestion to allow DNG conversion to include in its "envelope" native raw files is quite a good one and one which I shall mull over.
I too am cynical about ANY proprietry standards, but we seem to be lumbered with them!

petrovich
22nd March 2009, 07:20 PM
Everyone thank you for the replies to my questions.

1.) Adobe DNG converter (holy smokes I am not thinking at all) I have it as well......:o:o:o:o
2.) I have full Lightroom as well..........:o:o:o

I think I need to lay down in a darkened room and "matron bring me some medicine....":eek::eek::eek:

Regards

OlyPaul
23rd March 2009, 10:58 AM
Sorry to disagree again, but there are no guarantees in this world


Regards
Andy

No problem Andy and I did stipulate they were my preferences and thoughts.

And there are indeed no guarantes in this world but as with everything else you have two avenues... to make a choice or not make a choice, and as in all things only time will tell if you made the right one. ;)

HughofBardfield
23rd March 2009, 01:58 PM
My only current concern about using ORF is what I eventually do with the tens of thousands of ORF files on the by-then-about-to-become-redundant-for-some-organo-quantum-storage-device DVDs when I discover that Olympus are changing to the new 32-bit ORFIII format, and will no longer support plain ORF (probably in about 5 years or less at the current rate of change).

Will DNGs fare any better in the longer term I wonder, especially when compared to my 35 year old B&W negs and trannies today? :confused: