1 Reply Latest reply on Mar 28, 2008 3:06 AM by (Barry_Clive_Pearson)

    Fuji S5 DNG conversions - DPReview questions...

    Level 1
      Hi, I have a couple of questions about Fuji S5 DNG conversions that have come up on the DPReview Fuji DSLR forum.

      So, if you're so inclined (actually one of them is ultimately DSLR non-specific):

      1) If an S5 RAF is converted to DNG, is it one of the few formats that
      has forced "demosaic" (ie: converted to linear even if you specify not
      to). In which case the S&R pixels are converted in an HDR image I
      guess?

      Or is all the original S&R pixel data preserved in tact (ie: kept
      separate per a normal RAF file)?

      2) While DNG is supposed to be a more "ubiquitous" format, if you don't
      convert to linear, doesn't it require the DNG reader to actually
      understand to some extent the original RAW format? I mean, if it
      isn't demosaic-ed, isn't the converter going to have to understand
      to some degrees the embedded proprietary mosaic-ed format?

      In which case, not to put it down (sincerely), it doesn't seem as
      ubiquitous and all that more "portable" than the original format.
      Am I missing something?

      I base this in part on a converter (Raw Shooter Pro) I used that
      could supposedly handle DNG, but couldn't handle DNGs from a
      Fuji S2.

      Thank you very much in advance.
        • 1. Re: Fuji S5 DNG conversions - DPReview questions...
          Level 1
          Some answers at:
          http://www.barrypearson.co.uk/articles/dng/specification.htm#fujifilm

          (They refer to earlier Fujifilm cameras; I guess, without proof, that DNG will handle the S5 in a similar way).

          Quote from that page:

          "Fewer raw converters can process raw image data from Fujifilm "SuperCCD" & "SuperCCD SR" sensors than from Bayer sensors. Some users of Fujifilm cameras wonder why a "common raw file format" like DNG doesn't solve this problem.

          But no true raw file format can solve this problem! The photographer's use of "raw" postpones the processing of the raw image data to the raw converter, so that is where the necessary code must exist. Once that raw image data is in the memory of the raw converter, it doesn't make a difference to the code whether it came from a DNG file or a native raw file."

          See also:
          http://www.barrypearson.co.uk/articles/dng/profiles.htm#limit

          If software supports the DNG tags for offset sensors, then it should support any future camera from Fujifilm or (hypothetically) other manufacturers with such sensors. So it offers an improvement.

          DNG isn't magic. For example, if software can only handle 3 colours, it won't handle DNGs of a Sony F828. If software DOES support 4 colours in DNG files, it should support any other 4-colour sensor. There is no full substitute for supporting all the DNG tags instead of just some of them, although the latter is easy to develop, of course.