Pages: [1] 2 3   Go Down

Author Topic: Lightroom: DNG or RAW  (Read 22985 times)

Luvntravln

  • Newbie
  • *
  • Offline Offline
  • Posts: 9
Lightroom: DNG or RAW
« on: March 30, 2009, 12:28:30 am »

Hi,

Do you convert your RAW images to DNG before processing? If you do, why; if you don't, why?
Logged

DarkPenguin

  • Guest
Lightroom: DNG or RAW
« Reply #1 on: March 30, 2009, 12:56:43 am »

Not anymore.

Three reasons ...

The converter bakes in panasonic lens corrections so you can't get a DNG that hasn't already been demosaiced.

Keeping changes confined to external .xmp (read: small) files rather than entire DNG (read: large) files makes for smaller backups which is particularly handy when using online backup services like Mozy Home.

The Canon raw converter offers some features that are more of a pain to do in DNG supporting apps.
« Last Edit: March 30, 2009, 12:57:25 am by DarkPenguin »
Logged

digitaldog

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 20630
  • Andrew Rodney
    • http://www.digitaldog.net/
Lightroom: DNG or RAW
« Reply #2 on: March 30, 2009, 09:33:26 am »

Quote from: Luvntravln
Do you convert your RAW images to DNG before processing? If you do, why; if you don't, why?

Yes. The reasons are stated here:
http://www.ppmag.com/reviews/200709_adobedng.pdf


Logged
http://www.digitaldog.net/
Author "Color Management for Photographers".

Panopeeper

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1805
Lightroom: DNG or RAW
« Reply #3 on: March 30, 2009, 11:12:01 am »

Quote from: digitaldog
Yes. The reasons are stated here:
http://www.ppmag.com/reviews/200709_adobedng.pdf
Sorry Andrew, this is not so. Your paper deals correctly with the aspects of metadata editing. However, that has nothing to do with DNG; it works equally with native raws.

The difference is in reality where the metadata will be stored. You see embedding the metadata in the raw file as an advantage; I see it as a violation of the very basic principle, namely let the original untouched. If one does not want to archive the adjustment metadata, this is no problem; but if one does need that, the embedded metadata is disadvantage pure.

As to the file size: in times of terrabyte capacity on hard disk, the difference between the sizes resulted by two methods of compression is hardly a decivive reason. In fact, there are cases when DNG is larger than the native raw, but I would not mention this as an advantage of the native raw format.
Logged
Gabor

digitaldog

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 20630
  • Andrew Rodney
    • http://www.digitaldog.net/
Lightroom: DNG or RAW
« Reply #4 on: March 30, 2009, 11:22:03 am »

Quote from: Panopeeper
The difference is in reality where the metadata will be stored. You see embedding the metadata in the raw file as an advantage; I see it as a violation of the very basic principle, namely let the original untouched. If one does not want to archive the adjustment metadata, this is no problem; but if one does need that, the embedded metadata is disadvantage pure.

You are entitled to that opinion. I don't share it, nor do others. The very point of the DNG container IS to store this additional data. You or anyone else is entitled to save off the original Raw proprietary data. I want an up-dateable preview and one that I can control for printing outside a Raw converter (in fact, I look forward to multiple such previews).

As for the time to update the DNGs when backing up, its a moot point for me as well. I have this all happening while I'm asleep at night. I happen to feel that computers should do mundane work when we humans are doing other useful things.
Logged
http://www.digitaldog.net/
Author "Color Management for Photographers".

Panopeeper

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1805
Lightroom: DNG or RAW
« Reply #5 on: March 30, 2009, 11:42:17 am »

Quote from: digitaldog
You are entitled to that opinion. I don't share it, nor do others
Correctly it is nor do some others; but some other others do share my opinion. This is largely a question of workflow, but not only. Some computer ill- and semiliterates do not understand the implications; there are some, who don't even archive the original at all.

One of the implications is, that several, different versions of the entire file can be created. For example if someone creates a backup of the archive on red-only storage, one can end up with different versions of 20 MB files, where the difference is only a tag and perhaps the preview.

Let me quote Erik Chan, a Camera Raw Engineer, from an Adobe forum:

To be clear, Adobe did __not__ create DNG in the hopes that photographers shooting non-DNG raw files would suddenly convert them all to DNG files and then throw away their original non-DNG raw files. Instead, Adobe created DNG has an example of a documented format (a set of TIFF extensions) that would improve interoperability among hardware and software vendors, as well as be suitable for archiving
Logged
Gabor

digitaldog

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 20630
  • Andrew Rodney
    • http://www.digitaldog.net/
Lightroom: DNG or RAW
« Reply #6 on: March 30, 2009, 11:47:15 am »

Quote from: Panopeeper
Let me quote Erik Chan, a Camera Raw Engineer, from an Adobe forum:

To be clear, Adobe did __not__ create DNG in the hopes that photographers shooting non-DNG raw files would suddenly convert them all to DNG files and then throw away their original non-DNG raw files. Instead, Adobe created DNG has an example of a documented format (a set of TIFF extensions) that would improve interoperability among hardware and software vendors, as well as be suitable for archiving

That one can take a rendered TIFF or JPEG and place that into a DNG is a move I wish Adobe had not done. Its called Digital Negative. Adding the ability to place non Raws into the container really confused a lot of people needlessly.
Logged
http://www.digitaldog.net/
Author "Color Management for Photographers".

DarkPenguin

  • Guest
Lightroom: DNG or RAW
« Reply #7 on: March 30, 2009, 11:58:26 am »

Quote from: digitaldog
That one can take a rendered TIFF or JPEG and place that into a DNG is a move I wish Adobe had not done. Its called Digital Negative. Adding the ability to place non Raws into the container really confused a lot of people needlessly.

We need a digital positive.  Have a single container for a stack of conversions.
Logged

PeterAit

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 4559
    • Peter Aitken Photographs
Lightroom: DNG or RAW
« Reply #8 on: March 30, 2009, 12:30:20 pm »

Quote from: digitaldog
Yes. The reasons are stated here:
http://www.ppmag.com/reviews/200709_adobedng.pdf

The "reasons" in that article for converting to DNG don't make any sense if you bother to think about them a bit.

1) Store the metadata with in the same file. Duh, it's a digital NEGATIVE, meant to preserve all of the original image data WITHOUT CHANGES.

2) Non-proprietary format. Will all those who think that Nikon or Canon will go out of business or stop supporting their RAW format please raise their hands?

3) Smaller files. 1.5 terabyte hard disk = $140.

A possible reason for staying wth RAW is that the camera manufacturer might improve their software for processing their own RAW format, and we cannot be sure that these improvements will be available in rendering algorithms from Adobe or others.

Peter
Logged

DarkPenguin

  • Guest
Lightroom: DNG or RAW
« Reply #9 on: March 30, 2009, 12:35:46 pm »

Quote from: PeterAit
The "reasons" in that article for converting to DNG don't make any sense if you bother to think about them a bit.

1) Store the metadata with in the same file. Duh, it's a digital NEGATIVE, meant to preserve all of the original image data WITHOUT CHANGES.

2) Non-proprietary format. Will all those who think that Nikon or Canon will go out of business or stop supporting their RAW format please raise their hands?

3) Smaller files. 1.5 terabyte hard disk = $140.

A possible reason for staying wth RAW is that the camera manufacturer might improve their software for processing their own RAW format, and we cannot be sure that these improvements will be available in rendering algorithms from Adobe or others.

Peter
Re: Item 2.

*raises hand*
Logged

Panopeeper

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1805
Lightroom: DNG or RAW
« Reply #10 on: March 30, 2009, 12:46:04 pm »

Quote from: DarkPenguin
Re: Item 2.

*raises hand*
That's right; this is not an impossible scenario.

However, the relevant question is not if a big manufacturer can go out of business, but if the existing native raw files would be affected by that event.

NO. Although the manufacturer's own raw processor may become obsolate after some system changes, other, independent raw processors will not stop supporting the old file formats, nor will the DNG converter stop. In other words, the worst case is, that one needs to convert the native raw files in DNG if they can not be processed directly.
Logged
Gabor

digitaldog

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 20630
  • Andrew Rodney
    • http://www.digitaldog.net/
Lightroom: DNG or RAW
« Reply #11 on: March 30, 2009, 12:58:31 pm »

Quote from: PeterAit
2) Non-proprietary format. Will all those who think that Nikon or Canon will go out of business or stop supporting their RAW format please raise their hands?

They don't have to go out of business, just stop supporting the format. Kodak is still in business. Can I send you some of the very old DCS proprietary files I have that I can no longer open?
Logged
http://www.digitaldog.net/
Author "Color Management for Photographers".

Panopeeper

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1805
Lightroom: DNG or RAW
« Reply #12 on: March 30, 2009, 01:09:31 pm »

Quote from: digitaldog
Can I send you some of the very old DCS proprietary files I have that I can no longer open?
Why can't you open them with the old software?

Anyway, the existence of the DNG converter eliminates this problem.

Logged
Gabor

digitaldog

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 20630
  • Andrew Rodney
    • http://www.digitaldog.net/
Lightroom: DNG or RAW
« Reply #13 on: March 30, 2009, 01:18:00 pm »

Quote from: Panopeeper
Why can't you open them with the old software?

It only runs under OS9, no machines here run OS9! In fact, very old DCS files require even older OS's.

Same issue with PhotoCD scans. You have to run the acquire module under Rosetta, something that very soon will not be possible on newer hardware.
Logged
http://www.digitaldog.net/
Author "Color Management for Photographers".

madmanchan

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2115
    • Web
Lightroom: DNG or RAW
« Reply #14 on: March 30, 2009, 02:46:02 pm »

Just to be clear, Andrew, the quote of mine that Gabor posted above wasn't intended by me to support the notion of putting non-raw data in a DNG container.

Instead, I was trying to say that while some users may benefit from using the Adobe DNG Converter to produce DNGs from non-DNG raw files, in my opinion the real benefit of DNG (or at least some standard, documented raw format, whether it be DNG, TIFF/EP, or something else) is when they are generated directly by the camera.

In the case of DNG, for instance, an in-camera DNG can contain an image checksum, which DNG readers can use to check for image integrity after images have been read off the card (or at any other time). As another example, the makers can embed 1 or more color profiles to be used for portable default color rendering across DNG readers; Casio and Pentax have done this quite effectively, without having to divulge what recipes they used to cook up those profiles in their labs.

My original comment about TIFF extensions was simply about the fact that the low-level file format (in terms of its structure) looks like a TIFF, which makes it relatively easy to support for software developers who are already used to dealing with TIFF. Developers also have the option of just using the DNG SDK which is a basic DNG reader and writer.
« Last Edit: March 30, 2009, 02:48:48 pm by madmanchan »
Logged
Eric Chan

digitaldog

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 20630
  • Andrew Rodney
    • http://www.digitaldog.net/
Lightroom: DNG or RAW
« Reply #15 on: March 30, 2009, 02:57:14 pm »

Quote from: madmanchan
Just to be clear, Andrew, the quote of mine that Gabor posted above wasn't intended by me to support the notion of putting non-raw data in a DNG container.

Understood (and expected <g>). Before your time too.

As we've discussed, the integrity checking is another big plus for DNG.
Logged
http://www.digitaldog.net/
Author "Color Management for Photographers".

Nick Rains

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 705
    • http://www.nickrains.com
Lightroom: DNG or RAW
« Reply #16 on: March 30, 2009, 06:41:47 pm »

Quote from: Panopeeper
The difference is in reality where the metadata will be stored. You see embedding the metadata in the raw file as an advantage; I see it as a violation of the very basic principle, namely let the original untouched. If one does not want to archive the adjustment metadata, this is no problem; but if one does need that, the embedded metadata is disadvantage pure.

Gabor

Can you point to any evidence that shows that the output from a DNG file is in any way different to that from it's original RAW when both are processed in the same way with the same RAW converter? Your stance on the 'purity' of the original RAW data seems to me to be ideology rather than reality, but since you are obviously a well informed kinda guy I'd be interested to find out if you can show firm examples why you have this apparently deep aversion to DNG files.

In other threads Andrew and I have pointed out some practical advantages which are pretty well indisputable, all we have had back are what appear to be purely theoretical objections. If these are meaningful in the 'real world' then fine, I'd like to know more, but if not then they just confuse people..

Show me the Money!
« Last Edit: March 30, 2009, 06:45:20 pm by Nick Rains »
Logged
Nick Rains
Australian Photographer Leica

Panopeeper

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1805
Lightroom: DNG or RAW
« Reply #17 on: March 30, 2009, 07:28:26 pm »

Quote from: Nick Rains
Can you point to any evidence that shows that the output from a DNG file is in any way different to that from it's original RAW when both are processed in the same way with the same RAW converter?
I find it important to remove the condition processed in the same way with the same RAW converter for a variety of reasons:

1. different raw converters may interpret the same data differently (this is obvious for anyone, who tried the manufacturer's raw processor and any other one),

2. "processed in the same way" is past all boundaries of mushiness; what is the meaning of "same way" for example relating to noise reduction?

Quote
Your stance on the 'purity' of the original RAW data seems to me to be ideology rather than reality, but since you are obviously a well informed kinda guy I'd be interested to find out if you can show firm examples why you have this apparently deep aversion to DNG files
1. I do not have any "aversion" to DNG files. The DNG design is a small-minded patchwork, but that is nothing special. As the matter of fact, my related product, Rawnalyze started out with supporting only DNG files.

2. While I have quite a few objections re the DNG specifications, the subject in this forum is something different, namely if to convert native raw files to DNG.

3. I am not only well-informed, but I am experienced enough not to *absolutely* trust anything, which "comes out of computer", not even if I myself have programmed it.

4. A specific example for the raw to DNG conversion being "inventive" for the lack of DNG ways expressing something present in the raw file: Canon's sRaw files.

5. A specific example for the Adobe DNG converter causing destruction: see around post #26 in this Adobe forum

You are free to believe, that software coming out of the Adobe (or any other) door is free of error, but you are not free to expect, that any experienced person takes your considerations seriously.
Logged
Gabor

Nick Rains

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 705
    • http://www.nickrains.com
Lightroom: DNG or RAW
« Reply #18 on: March 31, 2009, 12:51:36 am »

Quote from: Panopeeper
2. "processed in the same way" is past all boundaries of mushiness; what is the meaning of "same way" for example relating to noise reduction?

You are free to believe, that software coming out of the Adobe (or any other) door is free of error, but you are not free to expect, that any experienced person takes your considerations seriously.

OK, I'd say that 'in the same way' meant exactly that. Open the file in the raw processor and export it using all the same parameters as the other file. is that rigourous enough?

Same NR value, same brightness value, same black point value, same, same etc etc etc. Same version of the same RAW processor too in case we are not clear. if this is not 'samey' enough for you then you are operating in realms of pedantry and sophistry way beyond us mere mortals.

"but you are not free to expect, that any experienced person takes your considerations seriously."

I was keeping this discussion respectful, as is my usual way, however this comment could be taken as rather patronising, maybe you meant otherwise...
Logged
Nick Rains
Australian Photographer Leica

Panopeeper

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1805
Lightroom: DNG or RAW
« Reply #19 on: March 31, 2009, 01:51:46 am »

Quote from: Nick Rains
OK, I'd say that 'in the same way' meant exactly that. Open the file in the raw processor and export it using all the same parameters as the other file. is that rigourous enough?
Somehow I "skipped" your  with the same RAW converter; I was thinking of conversions with different raw converters.
However, this is irrelevant; the criterion is not that the results be the same but that they are not erroneous. The error I showed in the example was identical when processing the NEF or the DNG.

Quote
I was keeping this discussion respectful, as is my usual way, however this comment could be taken as rather patronising, maybe you meant otherwise...
Have you actually read the post I linked to? You asked for evidence, and I provided one; note, that this is not the only case when the DNG converter created an erroneous output.

Anyone, who blindly believes in any program's error free functioning and throws away the original is naive, to say the least. This is not an issue with Adobe; Nikon's Capture X too made error when storing the adjustment parameters in the NEF file. Not a serious error, but enough to demonstrate, that the product did not go through a rigorous test.

Logged
Gabor
Pages: [1] 2 3   Go Up