I want to make a QUALIFIER up front: I am technical just enough to be dangerous.
The points which I ASSUME are true.
1. RAW file contains luminous data (0-4095 for 12 bits systems, for example) from pixels within the Image Sensor which has Bayer matrix pattern (or similar) overlay.
2. Data has been processed for ‘noise reduction’ via built-in electronics.
3. Data has been compressed.
4. RAW file contains Meta Data.
5. Phase One attaches a calibration data file for an individual image sensor according to LLVJ (approximately 1 meg file for P25 which corrects the responses of defective pixels; dead pixels and out-of-specs pixel responses, etc) to be used by its RAW converter, Capture One. I don't know how other MFDB manufacturers handle this issue, any one?
6. Leaf’s allows the uploading of ‘special programs’ to its Aptus DB so RAW files can be modified (per email from Mr. Shachar Kedem of Leaf to Michael Kravit,
http://luminous-landscape.com/forum/index....howtopic=12079).
It states ‘Gain functionality within Leaf Capture 8 enables creating and using gain corrections for specific lenses. We have developed a new version of Leaf Capture 8 which will produce User Gain files that can be loaded to the Aptus back and used during any shoot (including portable shooting).
Item 5 and 6 raise the questions about the RAW files and RAW Converters.
A special calibration file for Phase One DB makes senses as long as the RAW files are processed by its converter, Capture One. But, as far as I know, Phase One did not make their file protocol public, still certain 3rd party software supposedly able to convert the files even better than Capture One. Is it possible? Are they ignoring the calibration file?
Phase One can calibrate its DBs individually since they charge a lot for them, but what about Canon and Nikon? I am not talking about digicams but their high-end cameras, 1D’s and D2Xs’. Do they calibrate each image sensor? If they don’t, how are they dealing with the problems of non-uniform responses with pixels? I deduced LEAF do calibrate its sensors individually.
DPReview has been testing and comparing the performances of different cameras mostly with JPEG (how one is better to make red redder and lines look sharper than the others using its proprietary software). Are RAW files from Aptus DBs more than just RAW files? I am interpreting Mr. Kedem’s email as ‘image enhancing programs can be uploaded to its DB so its files can be processed in specific manner before it would be downloaded to a computer as RAW files.’
PLEASE COMMENT, IF I AM READING HIS EMAIL WRONG.
If one can load a program to a DB to fix the image sensor problem that Mr. Kravit was reporting by means of an ‘image enhancing program,’ can one also load ‘style/profile’ program to give images certain looks? Does Aptus DB do ‘image enhancing’ on its RAW files?
I understand how a better image sensor can create better RAW files with wider Dynamic Range, with wider ISO range, with lower noise ratio, with better designed micro lens (off-centered lenses for Leica M8), with ability to have long exposure, etc. But will these improvements (or advantage of one vendor to others) create better looks? A better design of Bayer matrix and decoding algorithms would bring better color rendition, less aliasing, and sharper images, but will it bring different looks?
For the record, I own P45, H2 and Arca-Swiss F6x9 View Camera with Schneider Digitar lenses. I also had Canon 1Ds until recently for three years.
Jae Moon
