Talk:Digital Negative

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If the PNG format is pronounced Ping - are DNG files pronounced Ding?Tigershoot (talk) 16:24, 19 September 2011 (UTC)

should probably be stated[edit]

If "raw"=uncompressed, this should probably be stated explicitly in the article... AnonMoos 15:59, 12 November 2006 (UTC)

  • "RAW" isn't uncompressed, in fact some RAW formats are indeed comprssed. Conversion from my Fuji's RAF format to Adobe's DNG format loses about 8 MB of size, with no image information lost. Camera RAW is an image captured by a digicam with no preprocessing in the camera. David Spalding (  )

  • RAW file formats can be compressed and uncompressed depending on the camera model and manufacturer. I know that higher end (D200, D3* series) Nikon cameras allow you to choose between compressed and uncompressed RAW (NEF) formats on the fly using the camera's built in menu system.

Here's a discussion on uncompressed vs. compressed Nikon RAW (NEF) formats: --Ryan Sinn 09:51, 1 November 2007 (UTC)

  • Does anybody have any idea on how "royalty free" DNG is? Is it royalty free because Adobe currently says so... or is it Royalty free in the same sense that the PNG file format is? --Ryan Sinn 09:51, 1 November 2007 (UTC)

Merge Adobe DNG Converter to Digital Negative (file format)[edit]

  • Merge per nomination. The converter isn't really notable except as a tool for the DNG file format. Exception might be from readers linking from Adobe Photoshop or Adobe Bridge wonderin gwhat the DNG Converter is for. But linking here instead makes sense, so the topic is fully covered (not just a tool for it). David Spalding (  ) 22:09, 29 December 2006 (UTC)
As far as I can tell, this was merged in May 2007! See History of "Adobe DNG Converter". Barry Pearson 15:59, 11 February 2010 (UTC)

Patent encumbered or not?[edit]

I have removed the term "patent encumbered" because there is no evidence for it. In fact, in September 2009 Adobe stated (in a launch of material for CinemaDNG) "There are no known intellectual property encumbrances or license requirements for CinemaDNG or its underlying formats DNG, TIFF, XMP, or MXF". The "Digital Negative (DNG) Specification Patent License" that was being cited as evidence for patents on DNG is not such evidence (and is more than 4 years older than the recent Adobe statement). That License does not state that there are patents on DNG, and certainly doesn't identify any. In effect, it says "whether or not there are any patents is irrelevant because you have the right to exploit DNG anyway". In other words, it eliminates the possibility of any such "encumbrance" upon the exploiter, and provides reassurance. Barry Pearson 15:43, 16 September 2009 (UTC)

I have been researching and debating DNG for nearly 5 years, and I have never found or been informed of a patent. I have searched the US Patent and Trademark Office site for any such patent, and I haven't found one. It is hard to prove a negative, but given that the License is not evidence for patents, and in view of Adobe's recent statement, I believe the onus is on anyone claiming that DNG is "patent encumbered" to identify at least one patent that encumbers DNG. Barry Pearson 15:43, 16 September 2009 (UTC)

Rationale for DNG[edit]

There was previously little to indicate why Adobe had bothered to develop DNG. (They don't charge for it!) Without this new section, it was possible to see DNG as "just another raw image format". In fact, it is unique in a number of ways, and this section has the task of summarizing these ways. It needs more detail, (and probably a few more references), and I will probably add some (as may others). But I believe there is enough at the moment, including several citations to verify the statements, to justify its inclusion. At the very least it identifies a structure within which further material can be added. I inserted this new section without changing anything on the page, to make it easier to see what I have just done. This has added considerably to the list of references, and they (and especially the "External links") need tidying up. I have started to use named references which should enable some duplication to be removed soon, and I believe all except 2 of the "External links" can soon be removed. Barry Pearson 10:56, 20 September 2009 (UTC)

I've done this tidying up of references, and also added several more references to the "Rationale" section. Barry Pearson 14:57, 22 September 2009 (UTC)

I have included references to one of my own websites (and of course Wikipedia warned about this). I am not the first to refer to this website where DNG is being discussed; other people here unknown to me (and without prior discussion with me) have also referred to this website over the years. Indeed, this page already had 2 such references long before I ever started to edit Wikipedia. (The US Library of Congress, and many other websites, also refer to my pages). This (sub-)website is unique: it has information about DNG that isn't collected in any other single source, even Adobe, and lots of it has never been published anywhere else because I conducted the investigations and "experiments". This may be a conflict with the Wikipedia "no original research" policy, but only if the latter is applied without also applying the "common sense" principle! One principle I apply on those pages is "verified truth" (in contrast with the Wikipedia "verification rather than truth" position). So I do simple original research, using specified freely available tools, and publish the methods and results. Anyone can repeat what I did and they would get the same results, but I don't know how to cite this in a non-controversial way. I can't transfer all of the information on the website into Wikipedia: many of the 30 or so pages are quite large, and contain many 100s of external references. (Interestingly, I suspect that it would be less controversial for others to refer to my pages than for me to. Yet what difference would it make?) Barry Pearson 10:56, 20 September 2009 (UTC)


I created a new section, based on material already in the pages for raw image formats and TIFF/EP but reworked to be more relevant to DNG. A summary was already at the top of the page, and I've removed this to avoid duplication and to make the top of the page simpler. Barry Pearson 14:15, 20 September 2009 (UTC)

Products that support DNG[edit]

I've restructured this as a short-term measure, but this section needs a lot of thought. Because the information is only a summary of other lists, I've merged the 2 previous major sections into a single section with subsections. Even then it is probably less than a 10th of the size of the source material. It is questionable how many products should actually be named here. It takes a lot of effort to keep such lists up to date - my own list has grown by 9 in the first 20 days of September 2009, including a few cameras! Adobe's list is way out of date. I am the only person who appears to be trying to maintain a comprehensive list, and it has over 270 products in all (although I claim far less than that to allow for obsolescence). I don't have time maintain the list on this page as well as my own. I think this page should have an illustrative overview, not an exhaustive list. Barry Pearson 16:32, 20 September 2009 (UTC)

I have a proposal for improving this section. The current products listed are only a subset of those that support DNG in some way, and the information is out of date, and somewhat inconsistently presented. So I certainly believe that something needs to be done to meet Wikipedia quality. I propose therefore to redevelop lists of camera models and software products as follows. Find models products that illustrate significant events or features, for example "first SLR", "first Linux based DNG converter", etc. And products that are well known already and so might be of interest to many people. Where there are multiple choices, try to find products that already have pages in Wikipedia, because they have past some sort of "notability" test, and using internal links will avoid too much clutter in the "References" section. Where there is still a choice, use products in the current lists because someone at some time thought those were significant. But don't include products just because they were once newsworthy - over the last 5 years, new products that support DNG in some way have been appearing at an average of more than 1 per week. And within those, new cameras that write DNG have been appearing at an average of more than 1 every 7 weeks. Even new camera models that write DNG are hardly noteworthy nowadays. I will probably (without malice!) remove a product that someone has a special reason for having on the page, so whatever I remove from the page I'll move here, so that it will be easy for someone to move individual products back without having to "undo" my whole change. Barry Pearson 14:26, 25 September 2009 (UTC)
If there is a view that there should be a much longer list, perhaps exhaustive, I believe it needs to be a separate page. With perhaps 270 products and growing, putting the list on the main DNG page will exceed Wikipedia page size guidelines. (My own page would print as 24 pages, and is more than 11,000 words). But I would advise against having such a page. (And I for one won't create one or spend any significant amount of time maintaining one). My observation of Wikipedia "List of X" pages is that they eventually cease to be exhaustive, and a page with the appearance of being exhaustive but isn't is misleading. Every year (on 27 September, the anniversary of the launch of DNG) I checkpoint my own list of products, and wonder whether to continue for another year. One year I'll stop, because of the effort involved. Barry Pearson 14:26, 25 September 2009 (UTC)

References and links[edit]

I have now tidied up the references and external links. I removed all but 2 of the "External links": the main Adobe link, which will reach everything important about DNG on the Adobe website; and my index page, will reach the majority of anything important about DNG on the rest of the web outside the Adobe website. Apart from these, all links should be justified by context, and that can be done by references from the body. I removed the "See also" section which appears to be a set of internal links to articles with little or no relevance to this page. If any of the removed links, internal or external, are thought to be important, they should be justified by providing some context for them. (I suspect they once had a context, for example a section of their own, but the context was removed, leaving these links as orphans). Except for the initial launch announcement from Adobe, I believe references to news articles that are years old but well after the launch are now irrelevant clutter. (Two of the "External links" I deleted related to a debate in 2006 on the now-stagnant OpenRAW website - time has moved on, and while I still believe what I said, the material is esoteric). I've removed a few references from the "products that support DNG" section, because this needs more tidying up, and it appears a bit perverse to select just a few of well over 200 products then clutter up the references section with links. These products should be treated as illustrative - it would be foolish for anyone to buy them because Wikipedia says so! People buying products don't need "verified references", they need "truth"! And they should be selecting from a comprehensive list, not just a small subset that someone put here. Barry Pearson 18:44, 20 September 2009 (UTC)

This completes the main tidying up activity - the overgrown material has been pruned back, and the rest of the page has been re-structured ready to be developed as a more coherent page. I do believe that we need a section on "DNG conversion". (Not a section on the Adobe DNG Converter alone, which is just one of perhaps 10 DNG converters existing in the world, 3 belonging to Adobe). There is still a lot of work needed, such as improving the English, adding more references, etc. Barry Pearson 18:44, 20 September 2009 (UTC)

Technical summary[edit]

I realized that this was an article about a highly technical topic but had little technical information in it! I've started a new section to summarize important technical information. There is not much there at the moment. Barry Pearson 17:22, 21 September 2009 (UTC)


I wondered whether to start a new section called "Criticisms" as a container for statements opposed to DNG in some way. Then I read a suggestion to call this "Reception" to avoid that somewhat negative word, so I've created this section as a container for both "pro" and "anti" (and even "silence"!) positions. The current contents don't have enough references (lack of time), and some of it looks as though it ought to be moved to the "Products that support DNG" section. (I'm sure there are some critical statements that can be put here!) Barry Pearson 17:22, 21 September 2009 (UTC)

I've just done the "move" I mentioned just above. Barry Pearson 14:57, 22 September 2009 (UTC)

Draft "Timeline" section[edit]

I am developing a new "Timeline" section. I am doing so on my user page. I intend to insert it in this article with a single edit that changes nothing else. (Then I may tidy up around it with subsequent edits). I intend to insert it on the 5th anniversary of the launch of DNG: 27 September, UK time. Please comment here or on my own talk page if you can help or have significant objections. Thank you. Barry Pearson 12:13, 25 September 2009 (UTC)

I've added the Timeline section. Perhaps it should be called "Key events and trends"? Perhaps it should use a table (but I don't yet know enough about Wikipedia tables to make it look good)? I think it should go just before "Reception", but perhaps both of these sections should go later? Perhaps the "Anniversaries" should be extracted as a separate subsection, in effect to separate "key events" from "trends"? I'll leave it for a while, and see if others do something with it. Barry Pearson 06:33, 27 September 2009 (UTC)

"Adobe have submitted DNG to ISO for incorporation into their revision of TIFF/EP" (???)[edit]

Can anyone confirm this? No DNG submission can be found on the ISO website (no published standard and no standard under developement), and the reference points to a non-existent article. I believe that DNG was never submitted to any standard body at all, and I suggest to remove that sentence altogether, or replace it by one stating that DNG was never submitted and remains owned by Adobe Systems, Inc. (talk) 12:49, 22 December 2009 (UTC)

There are a number references cited in the TIFF/EP and DNG articles. (Go to the sections on "Timeline for development and revision" and "Standardization" respectively). DNG is being used by ISO TC42 WG18 during the 5-year revision of TIFF/EP, (ISO 12234-2), to form the basis for interoperability profile 2 of the revised TIFF/EP. It is not intended to be a separate standard, so it is not a "standard under development", and the revised version of TIFF/EP has not yet been finalized for ratification, so is not a "published standard" (or draft). (And it will remain owned by Adobe until ISO takes it over, just as PDF did until ISO took that over). This use of DNG by ISO is a process that started before April 2007, and such processes are not publicly reported by ISO themselves, so news has to be obtained from elsewhere, often after plenary meetings of TC42 are reported back to other groups. (I don't understand the statement "the reference points to a non-existent article". I can read it). Barry Pearson 15:37, 22 December 2009 (UTC)
I omitted references that didn't add much extra information, for example this one from April 2008: "We've actually started talking to ISO [International Organization for Standardization] of potential standardization around a new RAW format. We've submitted DNG as something for them to consider." From Kevin Connor, senior director of product management for Adobe's professional digital imaging products. DPP Solutions: A Look At DNG. But it is useful in this Talk, and illustrates that this process has been visible in various publicly available material for years. One reference in the TIFF/EP and DNG articles is to an email (in April 2007) from a WG18 member. I personally received a copy of this email, and have communicated with the author so I can be confident of what it says, but obviously I can't show that here. However, it is archived at a number of places other than the link shown, such as: 2007.04.17 08:36 "Standard RAW File Format (fwd)" and Fwd: Standard RAW File Format (fwd). Barry Pearson 15:37, 22 December 2009 (UTC)


2 recent edits have said this article resembles a fansite. Yet the Wikipedia:Fancruft page (referred to by the "fansite" template) starts "Fancruft is a term sometimes used in Wikipedia to imply that a selection of content is of importance only to a small population of enthusiastic fans of the subject in question." DNG is a free-to-use file format, launched over 5 years ago, used by about 15 camera manufacturers, about 200 software companies, and millions of photographers worldwide. It is recommended by the US Library of Congress as an alternative to all other raw file formats, which are "Not recommended". It is currently being used by ISO in its revision of ISO 12234-2. That is NOT "a small population of enthusiastic fans"! It is authoritative endorsement of a genuinely unique raw file format.

The latest edit says "does feel like a fansite, doesn't mention any DNG limitations/disadvantages". What does "feel like a fansite" mean? Go to the Wikipedia:Fancruft article - it is talking about a different type of article entirely. That article says: "As with most of the issues of What Wikipedia is not in Wikipedia, there is no firm policy on the inclusion of obscure branches of popular culture subjects". And: "The term "fancruft" is most commonly applied to fictional subjects". Yet DNG is a technical format/specification, not obscure, and not fiction. What is being objected to?

The DNG article DOES mention limitations of DNG, for example: "Images from the Foveon X3 sensor or similar, hence especially Sigma cameras, can only be supported as Linear DNG"; the "mixed reaction" and the fact that "largest camera manufacturers have apparently never indicated an intention to use DNG"; "A few software products only support DNG from cameras that write DNG, and/or from cameras that they support via their native raw image formats"; "it has been reported in user forums that some versions of the Adobe DNG Converter don't preserve all the raw data from raw images from some camera models". (For that latter case, I had to cite user-forums! Normal Wikipedia rules would not allow this, and so might force a removal of one of the limitations! External sources of information about limitations/disadvantages are typically of poor quality, not up to Wikipedia's normal standards).

But the fundamental problem with the objection "doesn't mention any DNG limitations/disadvantages" is the assumption that there needs to be some disadvantages! Suppose that DNG didn't have any? (As I've pointed out, the article refers to some, but take the hypothetical case that there weren't any). Is it not allowed to have an article about something that doesn't have any known limitations/disadvantages? DNG was designed later than most other raw image formats, and it was specifically designed to eliminate flaws in other raw image formats. It is unfortunately not perfect, as the article makes clear, but it is not surprising that it has far fewer than alternative formats which were not designed to eliminate those problems. (Hence the endorsement from the US Library of Congress).

When something has been designed to have unique characteristics which many users and organizations consider to be advantages, and has been designed with some success to eliminate the problems of the "competing" things, stating cited facts with a neutral point of view will identify that that it has advantages. An article that didn't show the unique aspects of DNG would not be neutral, but would be biased against it. (This is largely covered in the "Rationale" section. I couldn't come right out and say what all experts know, which is that all those other raw image formats have those disadvantages. I ended up saying "it is hard to cite verification that other formats don't have them. Therefore, anyone who is concerned about a particular objective and/or characteristic can check the status of DNG here, but must check the status of alternatives elsewhere". That is really a cop-out - no one has evidence of other raw image formats with all those advantages, but it is hard to prove a negative. It is a pity if this gives the impression that DNG is not unique, but I don't know how else to say this under normal Wikipedia rules). Barry Pearson 16:36, 1 April 2010 (UTC)

Fixing and improving links[edit]

1: My website was off-line for a significant amount of time earlier this year. (The hosting service's virus-checker had a false-positive for some "Pictures to EXE" files, and deleted the site for safety). Various links were replaced with the Internet Archive version or were marked as broken. The site is back on-line, with the same material (sometimes updated) nearly always in the same place. I've repaired the links so that they point to where they would have pointed had the site not gone off-line. And I've replaced the "broken" marks once I've checked that the links now work properly.Barry Pearson 13:36, 15 October 2011 (UTC)
2: I've removed the 2 External links. The Adobe link was already used in a Reference, so was redundant. The other pointed to my whole set of DNG pages. In that set, different pages are "advocacy", "repeatable research", "verified details", "lists of products with citations", "analysis", and one was "speculation". This drew criticisms. So I've ensured that all the links to my website are to pages of the form "verified details" and "lists of products with citations". References shouldn't be criticised because other pages on the same website don't satisfy Wikipedia's standards; that would rule out a lot of References! Barry Pearson 13:36, 15 October 2011 (UTC) — Preceding unsigned comment added by Barry Pearson (talkcontribs) 13:01, 15 October 2011 (UTC)
3: When researching the new OpenRAW page, I found many articles of professional archivists and conservationists working for respectable organisations that were talking positively about DNG. This is an increasing trend. Obviously they didn't advocate camera maker's proprietary raw files before! Those are non-starters for long-term preservation. Instead, they would tend to suggest other (processed, not raw) formats such as TIFF. But where images start as raw, DNG is increasingly seen as a respectable or preferred option. Barry Pearson 13:36, 15 October 2011 (UTC)
4: There were several "links" to non-existent Wikipedia pages, for cameras that exist but don't have their own pages here. I've removed those links, while leaving the camera names in place. (I question whether they should even be documented here, given that they are not a complete set. But I believe that the list is desired by some here).Barry Pearson 13:52, 15 October 2011 (UTC)
5: I've repaired a few more links, and deleted a few where the original source appears to have been deleted. I've just tested every Reference, and all work (although I can't ensure that they are the best for each purpose!) I believe every internal and external link now works OK. Now to pour myself some wine! Barry Pearson 16:30, 15 October 2011 (UTC)


The article currently uses the term "scene-referred" without definition or reference. This is jargon, and as such cannot be used in WP. David Spector (user/talk) 15:18, 5 December 2012 (UTC)

I've added a link to the CIE definition of "scene-referred". Barry Pearson 14:27, 13 December 2012 (UTC)