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Three DNG Converter preference values will increase the size of the DNG files by a large amount:
3. "Embed Original".
You claim you are not doing 3, so you are probably doing 1 or 2.
A quick test of a 5D CR2 (about 12+MB) gives:
1. "Linear": 42MB
2. "Uncompressed": 26MB
3. "Embed Original": 23MB
I doubt if it is "1".
Thanks for the help guys. Yes, I never compress my files. So when the Raw file is uncompressed, turning it to a DNG will double the file size? I am sure that is the case here since I know I do not compress, but doesn't that seem weird? Doesn't Adobe say that the DNG is more of a re-packaging and not a conversion? So why would the file size increase so much? I know it says it is a lossless compression, but the way I see it, something has to be lost in order to compress. Something....So it is lose info or kill hard drive space. Or stay native CR2. Yikes.
>"So when the Raw file is uncompressed, turning it to a DNG will double the file size?"
If the original CR2 file was compressed, yes.
A CR2 file uses the same compression algorythm as a DNG. Thus you are maybe "uncompressing" the CR2 during the conversion to DNG.
If you choose to compress, you will not lose info, and end more or less with the same filesize.
>"So it is lose info or kill hard drive space. Or stay native CR2. Yikes."
the compression is lossless, in both cases (CR2 and DNG).
Why don't you use the lossless compression algorithm? Absolutely no data is lost. Not a single bit is changed. The image data is preserved EXACTLY. That is what "lossless" means--there is no loss at all. The "way you see it" is wrong.
The ONLY reason the uncompressed option is available at all is so simple third party utility programs can read the files if their programmers have not written the code to decode the lossess compression agorithm yet. Even this is less of an issue now since Adobe provides the free DNG SDK with source code that does this decoding.