R.G. wrote:
And others. That's where you enter into the murky world of proprietary formats. That's where each proprietary format requires format-specific software to open the file. Even within a single company there can be more than one raw format.
And the advantages? None that I can think of. Raw data is raw data, and none of these proprietary formats are doing anything any better than DNG. Some are more compact than others, but that's an area where DNG has a distinct advantage.
Just for the sake of pedantic accuracy, this isn't really about proprietary formats, it is about open and closed formats. Also, there are advantages and disadvantages to the use of formats like DNG and standards such as JPEG or TIFF that have differing effects upon different people and organizations. Before I continue, I have nothing against the use of DNG, it is just another format and it does have value, but in the interests of accuracy, please consider the following.
1) At this time DNG is a proprietary format owned by Adobe. Adobe has proposed DNG as a formal standard to ISO, but it has not yet been accepted as such. It is an open and published format which is royalty-free and Adobe states that it is unencumbered by any known IP or license restrictions. It is not open source.
2) Adobe actively encourages its adoption, and the use of a vendor independent raw format that may become a formal standard has much value to end-users and some advantages as well as some disadvantages for vendors.
3) The advantages are fairly clear, including portability of raw data and the opportunity for camera and software vendors to adopt an open, royalty free specification without the cost of developing and maintaining their own format or reverse engineering closed proprietary formats from other vendors including Canon and Nikon.
4) The disadvantages for vendors can be manyfold. Adobe could change the specification or the licensing terms at any time if it wished to, although there is no indication that they do wish to or would benefit from such action. It does however remain a potential business risk.
5) It takes a long time for formal standards to be adopted, and when that happens it restricts the ability to change those standards without repeating the same lengthy and expensive process. An example is JPEG. The widely adopted JPEG has been superseded by newer versions of the standard that offer advantages, however they have not yet been widely adopted.
6) For vendors such as Canon, Nikon and others the advantage of proprietary raw formats gives them the freedom to change anything they wish to, potentially accelerating product development and freeing them from compliance with specifications that are not under their control. It is purely a business trade off. Adobe would benefit from its own technology being adopted as a standard, Canon and Nikon most likely would not gain much advantage and thus are unlikely to justify the cost of supporting DNG at least until it becomes a formal standard.
7) Adobe and others have reverse engineered the ability to use Canon and Nikon raw formats and as such the implementations may vary as may any default parameters applied upon import, whether 'neutral' or modified. Nikon, Canon and maybe others offer free software to process their raw formats. In the case of Canon (DPP) the raw data is transferred as are the in camera settings by default, so at first import the JPEG and raw (.CR2) files appear identical. However, in the case of Canon raw (.CR2) neutral and many other options can be applied and also customized. I see no downside to that from my own perspective.
In conclusion, it is quite a murky world where clarity is sometimes difficult to achieve. I suggest that there are advantages and disadvantages to either approach, and that depends upon the perspective of the individual or organization that is making a choice.
What this should not be is some kind of religious or moral judgement where some claim that their approach is superior except from their own perspective. We should also remember that things change over time, and with technology that can happen slowly or extremely fast. Predicting the future is a risky business.