Adobe DNG

[Paul Goss]

Hi

Adobe have a DNG convertor that allows you to convert your RAW files into it's 'Open' DNG format.

Does anyone know if this conversion means that there is a loss in picture quality and if so is it really noticeable. This maybe an answer for those who want to use Aperture but have cameras that have RAW formats that are not supported.

Thanks, Paul

 

[Conchita]

There is no loss of quality, but unfortunately you may find that DNG is not as universal a format as you thought (ie not all DNG is supported everywhere, either). Try a photo or two before doing a mass conversion.

 

[Paul Goss]

Have had a go and it reduces the file size. Wonder how it does that without compression or loss of quality. Any idea?

 

[Conchita]

It does lossless compression, like you can have for Tiffs. So it's compressed, but not with the kind of lossy compression that Jpeg uses.

 

[leicaman]

The Idea behind DNG is that you SHOULD have a file format that will not be outmoded 20 years from now... IE Adobe has pledged to support this format from here on out. This is not a given for CR2 or any other camera manufacturer's RAW output. You can also choose to have the conversion retain the full original RAW file as well. If you use ADOBE or other mainstream editors like LightZone you should have no trouble using these files many years down the road.

 

[Conchita]

That's the theory, anyway.

 

[PTamborini]

At least, the specifications are open, i.e. every moderate skilled programmer should be able to handle DNG files; in contrast to this, all other RAW formats are company secrets and if the company goes down, eventually the format goes down as well (if you have 25 years computer experience, you know what that means. Try to convert a Filemaker 2.0 File directly to a actual version: you'll have substantial problems.

Greetings
--
pt

 

[noirdesir]

Except for that a lot of raw file types are documented in that open source software is able to open them.

The question is, as long as Adobe will support the DNG format, won't it also support the DNG converter?

 

[leicaman]

Adobe has pledged to continue the DNG standard Ad Infinitum

 

[Cutterpillow]

Unless you really, really, REALLY know what you are doing.

Support for DNG is, in most cases, not nearly as large as it is for native RAW formats (NEF, CR2, etc.). If you convert to DNG you are limiting the software that you can use your images with. Also, conversion to DNG is a one way street - once you convert your images to DNG there is no going back to the original image. If you throw your originals away they are gone forever.

Some say that DNG is more "open" and your are guaranteed that it will be supported in the future while other formats may go away and lose support. This is false and I share some words from another thread:

http://forums.dpreview.com/forums/read.asp?forum=1017&message=27277283

What makes you think converters that understand that NEF will not be
around just as long (or longer) than DNG? Consider the knowledge to
read the RAW data from the NEF is already held in this open source
program, DCRaw:

http://cybercom.net/~dcoffin/dcraw/

As long as there is a C compiler on this planet you will be able to
read data from that RAW file. DNG is an open spec but still largely
a product of a single company, Adobe.

One of the biggest problems that I have with DNG is that you have to trust Adobe and their DNG Converter to always do the right thing and always do it right, with no bugs. I'm sorry but there isn't a program on the planet that hasn't seen its share of bugs. And I wouldn't trust anyone to convert my original image files into another format perfectly 100% of the time, all the time. Not to mention that Adobe recently had to pull the Lightroom 1.4 and ACR 4.4 updates because they introduced a bug in their DNG converter:

http://blogs.adobe.com/lightroomjournal/2008/03/important_lightroom_14_and_cam.html

-----------------------------------------------

DNG Conversion Error(Windows Only): With the latest version of the Lightroom 1.4 and Camera Raw 4.4 applications, Adobe has included technology to verify that the image data in a DNG file is unchanged from when it was originally converted to DNG. Unfortunately, when converting to DNG using Lightroom 1.4 on Windows, the application will write an incorrect verification tag to describe the image data. When Lightroom attempts to work with those files in the Develop module, the application reads that incorrect tag, believes that there is something wrong with the raw data and will present an error. Rest assured, there is nothing wrong with the integrity of your image data or metadata. For those that have already converted their files to DNG using Lightroom 1.4(Windows only) we recommend using the DNG 4.3.1 converter to convert the DNG files you’ve created with Lightroom 1.4.
-----------------------------------------------

This didn't actually compromise any image data, but it did make it so you couldn't edit your images in Lightroom.

Unless your camera's native RAW format isn't supported by the application you want to use then I would highly recommend against converting your original images to DNG. And even if your camera isn't supported and you need to convert to DNG for compatibility then I would recommend keeping the original files. There's very little benefit (if any) in converting images to DNG while there are a lot of drawbacks and risk involved.

Dave

 

[Conchita]

Yes, but will adobe be in the digital imaging business ad infinitum?