CR2 to DNG ??

[neil_ross]

Hi all, on my wifes laptop we only have cs3 and it wont read the 7d cr2's, to over come it we converted the cr2's to DNG's but i have a few questions.

does it lose quality? some searches would say not but i thought i would ask anyway.

do many of you do this? im tempted to do it even for the ones i process from cs5 as they seem to open up a lot quicker in bridge...

[donoreo]

It is not supposed to lose any quality. You are really just converting from one RAW format to another. I know that a lot of people who use Lightroom have it configured to convert to DNG on import.

[neil_ross]

ahh i see, in that case i might just stick to dng, it seems the xmp is embedded into the actual file aswell, is that correct?

[GeoffWessex]

That's correct - and therefore it saves 'littering' your folders with XMPs.
I'm not sure all camera makers should follow any rules set by one company, in this case Adobe, but if the DNG file format were to be adopted (if only as an option) by all cameras we wouldn't have to keep updating software to cater for the different Raw formats.

[AndyStevens]

And that's the key I think Geoff - if DNG were adopted as a standard, who would need anything better than CS2? Adobe et al keep upping the game so we keep updating and spending money with them.

[KeithT]

DNG should be the way forward for all camera manufacturers in my view. It is a universal format that can be recognised by all raw converters. It also reduces the file size by using lossles compression and includes the xmp info thus, as Geoff has pointed out, they won't litter yourharddriver with sidecar files. We should all fight for the right to have this format built in to our cameras.

[chris-p]

Couple of things. Firstly, Goeff - you don't have to store xmp files. You can store data in the RAW archive which saves generating xmp's

Secondly, DNG is not a direct replacement for your CR2 files, you will loose any encrypted data in the RAW file and DNG is only as stable as Adobe. It's not the open standard people think it is, much of the DNG encoding is actually not open at all.

Sadly, as the openRAW campaign disbanded thanks to pressure from Adobe and a lack of interest in a genuine open RAW system, DNG is the best option but it's not a perfect like-for-like conversion and it's not a universal format.

[neil_ross]

Cheers everyone, so Chris what data will you lose?

[chris-p]

None of the RAW formats are open and they contain lots of information which only the manufacturers know about. In fact there are so many different RAW formats that the open source RAW convertor DCRaw currently supports over 377 different formats.

There are differing opinions on this but, personally, I don’t think DNG is the answer. It is not a true open standard because it doesn’t document all the essential information in proprietary RAW files, only that which Adobe can work out.

Lots of data in proprietary RAW files is/may be encrypted. For example, Sony encrypted the RAW files on it’s F828 camera in 2003 and when Nikon released the D2X in 2005 it encrypted its white balance data within the RAW files. They weren’t the first or last companies to do this. It's done to stop other camera manufacturers unravelling their proprietary systems.

So if there is information in your .CR2 file that Adobe don’t understand or can’t decode (usually EXIF data, or encrypted data or other things) it won’t be in the .DNG file.

In the long run, there isn’t an answer to this problem. DNG works OK but if Adobe disappear then so does DNG. PSD is a good storage format, it supports layers and it’s lossless which is a huge advantage, but again, if Adobe fall so does PSD.

Many people argue the best long term solution is TIFF. But TIFF has it’s own technical issues, aside from being harder to implement, including a maximum file size of 2GB and no UNICODE support.

[Forseti]

Originally Posted by chris-p

So if there is information in your .CR2 file that Adobe don’t understand or can’t decode (usually EXIF data, or encrypted data or other things) it won’t be in the .DNG file.

For example, the profiles that one can set in camera (Canon) such as Landscape, Portrait and Neutral etc. These can be read by DPP but not by Adobe software. I don't use these by the way.

Originally Posted by chris-p

In the long run, there isn’t an answer to this problem. DNG works OK but if Adobe disappear then so does DNG.

Which to be fair is HIGHLY unlikely.

Originally Posted by chris-p

There are differing opinions on this but, personally, I don’t think DNG is the answer.

But probably the best option so far and one that has come to my rescue. I once owned a Canon G5 - lovely little camera that produced raw files in the format CRW. Two models later I think (the G7) Canon dropped support for the CRW format in favour of CR2 - in other words, I couldn't open/edit these CRW files in Canon's own softare - DPP. This is the prime reason I stopped using, or having faith in DPP, as good as it was and apparently still is. Who came to the rescue with their DNG converter? Good ole Adobe of course and I for one am a firm believer in the DNG format. Some day, not tomorrow perhaps, but Canon will change/drop the CR2 format and we'll have the same old story repeated. As it is one CR2 raw file is not the same as another CR2 raw file despite having the same suffix.