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DNG, Are we REALLY not throwing any information away with DNG?

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Deorum

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... over RAW?

I 've done a lot of reading, it all comes down to this.
-12% to -15% file size.

Sorry, but my camera files are not 20% small, but more like 13% smaller. (1ds ii). Maybe different cameras have different ration, i dont know.

Also I am not convinced about the futureproof of DNG over CR2. For me CR2 are as futureproof as they can be. Nobody will abandon them.

Smaller size is indeed an advantage. But do we really keep ALL the info there is? not WB applied, no sharpening, no NR, nothing nothing nothing just like original RAW?

--
George Spyros,
http://www.georgespyros.com
 
Ok, i did a test in 1ds3 file, and the size reduction is indeed from 28.2mb to 23mb, so the -20% is real.

--
George Spyros,
http://www.georgespyros.com
 
How can you ever know (for 100.0000% sure)?

Archive the files that came directly from the camera. Don't subject them to some funky conversion which must always carry some finite risk of introducing problems.
 
There are DNG file conversions and DNG from the camera. I'm not sure DNG conversions offer many advantages to me except possibly converting from some other form for the purpose of processing. I've noticed DNG conversions from CR2 RAW images processed in Photoshop retain the adjustments made to the image. I would rather save the originals before any adjustments.

DNG files direct form the camera offer the advantage no lost data and not needing new software every time a new camera comes out. Leica, Pentax and Ricoh are the only cameras I know of that offer DNG direct from the camera but several digital back makers have stated they will offer it in the future.
 
Yes I know that, but tbh in LR, you just save the adjustements too to the catalog file, so a big advantage of DNG is already available for cr2 files.

But for example newer canons shot 14bit RAWS. Are DNGs 14bit? Are DNGs as rich in information (shadows/highlights/color depth) as cr2?
Glenn Haley said:
There are DNG file conversions and DNG from the camera. I'm not sure DNG conversions offer many advantages to me except possibly converting from some other form for the purpose of processing. I've noticed DNG conversions from CR2 RAW images processed in Photoshop retain the adjustments made to the image. I would rather save the originals before any adjustments.

DNG files direct form the camera offer the advantage no lost data and not needing new software every time a new camera comes out. Leica, Pentax and Ricoh are the only cameras I know of that offer DNG direct from the camera but several digital back makers have stated they will offer it in the future.
Click to expand...
--
George Spyros,
http://www.georgespyros.com
 
I was also curious and ran a series of conversion tests using CR2 files from both a 5D MkII and G1X (both 14 bit) and I could see no difference between CR2 conversions and DNG conversions when processed in either CS5 or Capture One Pro.

If there are any differences between conversions and I could not see them in either highlight and shadows, contrast and color saturation there for as far as I'm concerned they would not matter.

But for me it's a mute point as I don't use DNG conversions unless I can't process them with my existing software. Given the choice I would prefer a camera that used DNG rather then some proprietary type of file.
 
Deorum said:
But for example newer canons shot 14bit RAWS. Are DNGs 14bit? Are DNGs as rich in information (shadows/highlights/color depth) as cr2?
Click to expand...
Any format that claims to be generic and future proof must provide support for such basic requirements as differences in bits per pixel, and certainly DNG does.
BTW, 14-bit color depth is nothing new: Minolta Dimage 7 had it 10 years ago.
--
Peter
 
Well, I acquired 14bit RAWS just few days ago, with my newer canon.

In fact 7-10 years back, 1) I didnt had an d-SLR 2) When I got an SLR CF prices were high, and in long travels i rarely shot raw. 1gb costed me 100euros, or something

:P
Peter Szymiczek said:
Deorum said:
But for example newer canons shot 14bit RAWS. Are DNGs 14bit? Are DNGs as rich in information (shadows/highlights/color depth) as cr2?
Click to expand...
Any format that claims to be generic and future proof must provide support for such basic requirements as differences in bits per pixel, and certainly DNG does.
BTW, 14-bit color depth is nothing new: Minolta Dimage 7 had it 10 years ago.
--
Peter
Click to expand...
--
George Spyros,
http://www.georgespyros.com
 
Deorum said:
Also I am not convinced about the futureproof of DNG over CR2. For me CR2 are as futureproof as they can be. Nobody will abandon them.
Click to expand...
Big difference is that DNG is open format, anyone can write software to handle DNG files.

CR2 is Canon's proprietary format so if Canon goes belly up you might have problems reading CR2 files in the future.
 
Archer66 said:
Big difference is that DNG is open format, anyone can write software to handle DNG files.
Click to expand...
But then, how come every raw converter can handle CR2 files? I mean, you first need to "decode" CR2 file to create DNG.
Question: are you "everyone" who can write software that can handle DNG files?
Archer66 said:
CR2 is Canon's proprietary format so if Canon goes belly up you might have problems reading CR2 files in the future.
Click to expand...
What are you talking about? Why do you think we won't be able to open CR2 files all of sudden? If file can be open now (meaning, "decoding" process is known), this can be done anytime in future. Or do you think knowledge will disappear as well (at the same time Canon goes "belly up")?

Bottom line: if you don't know about stuff, don't spread FUD ( http://en.wikipedia.org/wiki/Fear,_uncertainty_and_doubt )

Bogdan
 
hbx2004 said:
Archer66 said:
Big difference is that DNG is open format, anyone can write software to handle DNG files.
Click to expand...
But then, how come every raw converter can handle CR2 files?
Click to expand...
Can Nikon Capture NX open CR2 files ?

Can Sony software open CR2 files ?
hbx2004 said:
I mean, you first need to "decode" CR2 file to create DNG.
Question: are you "everyone" who can write software that can handle DNG files?
Click to expand...
Sure, Adobe has a SDK available for everyone to download.

http://www.adobe.com/support/downloads/dng/dng_sdk.html
hbx2004 said:
hbx2004 said:
CR2 is Canon's proprietary format so if Canon goes belly up you might have problems reading CR2 files in the future.
Click to expand...
What are you talking about? Why do you think we won't be able to open CR2 files all of sudden?

If file can be open now (meaning, "decoding" process is known), this can be done anytime in future.
Click to expand...
Official specification for Canon CR2 format is not available, sure you can find info about it but can you be sure it's 100% correct ?
hbx2004 said:
Or do you think knowledge will disappear as well
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I doubt those who have created CR2 format are alive 80 years from now. I also doubt that computers that can run current conversion software are available at that point.

But hey, not my problem if you want to save your legacy for your great-grandchildren in a format they might or might not be able to read.
hbx2004 said:
Bottom line: if you don't know about stuff, don't spread FUD ( http://en.wikipedia.org/wiki/Fear,_uncertainty_and_doubt )

Bogdan
Click to expand...
 
Of course, Nikon, Sony, etc. are not interested to support format of competition -do I realy need to tell you that?

I know where to download software. My question was, if you can write software that can handle DNG files. Btw. here you can download source code for 99% of all raw formats out there:
http://www.cybercom.net/~dcoffin/dcraw/

How can I be sure it's 100% correct? Well, what do you think how i.e. Adobe does (or did) that?

It doesn't matter if people who created CR2 are alive or not: once we know how to process CR2 files, those people are not relevant anymore. We don't need ancient Etruscan people to be able to read latin alphabet today, do we? Galilei, Newton and some other smart persons don't live anymore, but people can still fly to the moon. I hope you get the point.

Bogdan
 
hbx2004 said:
Why do you think we won't be able to open CR2 files all of sudden? If file can be open now (meaning, "decoding" process is known), this can be done anytime in future.
Click to expand...
Format obsolescence is a real issue. 20 years from now you may be using some new type of hardware running some new kind of operating system which won't run today's programs. You're basically hoping that the file formats you rely on will be popular enough that new software will be written to run on whatever future hardware and OS environments you may end up using.

CR2 is popular enough that it probably won't be a problem. But it's very short-sighted not to at least consider these kinds of issues.
 
Archer66 said:
Deorum said:
Also I am not convinced about the futureproof of DNG over CR2. For me CR2 are as futureproof as they can be. Nobody will abandon them.
Click to expand...
Big difference is that DNG is open format, anyone can write software to handle DNG files.
Click to expand...
Open? NO. Open means anyone can contribute and enhance the specifications. On the contrary, DNG is a proprietary format of Adobe. I never found any trace of it on http://www.iso.org: Adobe is the sole owner of the specifications and can change them at will without any obligation to document the changes or ask anyone before doing so.

In fact, they just did: "DNG" files emitted by Lightroom 4 with the new "fast load" and / or "lossy" options are entirely undocumented and unreadable by anyone else as far as I know. LR4 and LR4.1 are out since a long time now, but still no "DNG 1.4" specs in sight, and no "DNG 1.4" SDK either.

Those files are no longer DNGs as we know it and locks users into LR4 and the corresponding ACR only.

--
Axel
http://www.fastpictureviewer.com
 
AxelR said:
Archer66 said:
Deorum said:
Also I am not convinced about the futureproof of DNG over CR2. For me CR2 are as futureproof as they can be. Nobody will abandon them.
Click to expand...
Big difference is that DNG is open format, anyone can write software to handle DNG files.
Click to expand...
Open? NO. Open means anyone can contribute and enhance the specifications. On the contrary, DNG is a proprietary format of Adobe. I never found any trace of it on http://www.iso.org: Adobe is the sole owner of the specifications and can change them at will without any obligation to document the changes or ask anyone before doing so.
Click to expand...
I didnt claim it's open source, thats totally different thing.
 
Hey guys,

I appreciate your arquments, but my concern is not futureproofness. It is richness of informartion.

For example, is Sharpening applied to DNGs that is destructive to the original image?
And similar questions like BIT depth, highlights, shadows, etc.

I believe the answer was that YES, DNG file is as "original" as the CR2 file. But then you are not sure.

For futureproofness, i dont believe we will ever have a problem, and if we do, just before we switch OS or Hardware, we will convert then.

Although I am sure, that with this huge database of canon users, there will be a workaround, as I am sure, there is now for lotus or SAM editors (havent search it i am just guessing).

And dont forget back then Computers were in their's infant age. Things are more mature now.

--
George Spyros,
http://www.georgespyros.com
 
In one sense there is a loss - there are packages that can read most RAW files, but not DNG. I'm thinking of DxO here, but I'm sure that there are others.

You can always embed the RAW in the DNG, but I'm not sure why you would want to...
 
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