Sony's new DSLR RAW files small

Discussion in 'Sony' started by RichA, Jun 6, 2006.

  1. RichA

    RichA Guest

    From dpreview:
    · RAW (12-bit,.ARW format, approx. 9.1 MB per image)

    Files (RAW) from a 5 meg camera are usually 10 MB, from something like
    the Nikon
    D200 they are HUGE. Sony is a 10Meg camera as well.
     
    RichA, Jun 6, 2006
    #1
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  2. RichA

    tomm42 Guest

    Obviously the files are compressed, the noncompressed files in the D200
    are 15+mb, compressed they vary between 7 and 11mb (my experience).
    Either Sony is not including some info in the files or they are
    compressing them.

    Tom
     
    tomm42, Jun 6, 2006
    #2
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  3. RichA

    JR Guest

    Compression which leads to loss of information....in most cases you wont
    see it, when you do, there is nothing you can do about it. On my D2X I
    have it set for uncompressed RAW files, you have the option to compress
    and lose information but save file space, or leave uncompressed. When
    information is lost its usually in the highlights.

    JR
     
    JR, Jun 7, 2006
    #3
  4. RichA

    franklin.sr Guest


    Are you sure that they don't apply some form of lossless compression?
    What would be the point of lossy RAW file? Wouldn't that kind of defeat
    the purpose?
     
    franklin.sr, Jun 7, 2006
    #4
  5. RichA

    Dmac Guest

    Sounds good for those who don't know how to extract the information and
    just use a basic conversion program like Irfanview.
     
    Dmac, Jun 7, 2006
    #5
  6. RichA

    J. Clarke Guest

    For reason or reasons unknown Nikon chose to implement a lossy compression
    algorithm on the D2X. Not one of their better decisions IMO but perhaps
    they couldn't figure out how to implement a lossless one that achieved a
    high enough compression level to be worthwhile.
     
    J. Clarke, Jun 7, 2006
    #6
  7. RichA

    JPS Guest

    In message <>,
    That's the Nikon way, but for most other compressed RAW formats, there
    is no loss; it is like a .zip file.

    I imagine that RAW data would compress well with separate bitplanes with
    run-length encoding for the 8 most significant bitplanes, and then 4-bit
    nibbles uncompressed for the least significant bits. That would take
    longer to write and read, though, without special-purpose CPUs.
    --
     
    JPS, Jun 7, 2006
    #7
  8. RichA

    JPS Guest

    In message <>,
    To some degree; having posterized highlights as in the compressed NEFs
    probably reduces the advantage of exposing to the right a little, and
    creates a little more noise when you boost the saturation of contrast of
    the highlights, but the shadows are still untouched (up to about RAW
    level 163, IIRC). 163 would typically be the "middle grey" value of the
    red channel, and a stop below it in the green channel.
    --
     
    JPS, Jun 7, 2006
    #8
  9. RichA

    bmoag Guest

    Sony has no real experience with compressed raw files in their high end EVF
    cameras. Also they have no experience with tuning exposure to maximize
    pictorial information captured in the raw format as, for example, Nikon does
    with its dSLRs. It will be interesting to see what Sony has done with the
    base Minolta design when these cameras are finally available in the real
    world. If I had a collection of Minolta auto-focus lenses I would have one
    of these Alpha cameras already on order.
     
    bmoag, Jun 7, 2006
    #9
  10. RichA

    Jeff Rife Guest

    bmoag () wrote in rec.photo.digital.slr-systems:
    The Alpha is essentially an upgrade of the Minolta 5D. I'll wait for the
    Sony upgrade to the 7D. I'll take the ease of use of the 7D over a few
    more pixels any day.
     
    Jeff Rife, Jun 8, 2006
    #10
  11. Hi,
    +1 - I was disappointed by this too : the body clearly shows 5D filiation by
    the lack of rear wheel, and other buttons for direct access to functions,
    which is /the/ reason why I like my 7D.

    Regards,
     
    Stéphane Guillard, Jun 8, 2006
    #11
  12. · RAW (12-bit,.ARW format, approx. 9.1 MB per image)

    Files (RAW) from a 5 meg camera are usually 10 MB, from something like
    the Nikon
    D200 they are HUGE. Sony is a 10Meg camera as well.

    You are assuming that the format is 3 bytes per pixel (although 12 bits
    suggests that the colour depth is a measly 4 bits each!). There is nothing
    in the rules to say that they can't use simple space saving techniques (like
    run length encoding) or more sophisticated lossless compression (like zip or
    lharc). Even MS Windows XP will compress your raw files without loss (but
    only on an NTFS drive).

    OTOH if they apply Jpeg in any but its trivial configurations there will be
    data loss and (at higher compression) artefacts in the image.
     
    R. Mark Clayton, Jun 8, 2006
    #12
  13. this is invalid assumption. Each pixel in RAW file holds just one
    channel information in 12bits, so the "natural uncompressed" size of
    10Mpx, 12bit RAW file is 10e6 * 12 / 8 = 15MB, plus metadata overhead .
    This is certainly true for D200 - uncompressed RAW size is 15.8MB. Given
    that Sony's RAW 10Mpx image is just 9.1MB, the file is obviously
    compressed, but there is nothing (yet) to suggest that the compression
    is not lossless.


    B.
     
    Bronek Kozicki, Jun 8, 2006
    #13
  14. RichA

    JPS Guest

    In message <>,
    It suggests no such thing. It suggests that the red resolution is 50%,
    the blue resolution is 50%, and the green resolution is 71%.
    --
     
    JPS, Jun 8, 2006
    #14
  15. RichA

    JR Guest

    Just turn it off and forget about it......CF cards are CHEAP now.....I
    can get a 4gb microdrive for $69...why worry about compression....And
    for 99% of the shots, you dont notice the compression...I didnt in my
    tests, but why risk it....

    JR
     
    JR, Jun 10, 2006
    #15
  16. RichA

    Kevin Agard Guest

    The RAWs from a KM 7D are roughly 8 megs at 6.1 mp and as far as I know
    they aren't compressed.
     
    Kevin Agard, Jun 10, 2006
    #16
  17. RichA

    Jeff Rife Guest

    Kevin Agard () wrote in rec.photo.digital.slr-systems:
    The Alpha has a new image processor chip inside (the "Bionz"...whatever
    that means). Maybe among the things it can do is fast lossless
    compression of RAW files.

    --
    Jeff Rife | "Isn't that just great? I can't find a real
    | relationship...I'm incapable of meaningless
    | sex...what does that leave me? Oh, my
    | God...I'm gonna have to learn computers."
    | -- Jon Cryer, "Partners"
     
    Jeff Rife, Jun 10, 2006
    #17
  18. RichA

    Alan Browne Guest

    I have over $10,000 in 6 Minolta lenses (+2 TC's). I'm in no hurry to
    buy the A100. It is really a glorified P&S. Sony will have to do MUCH
    better than the A100 to convince me that they're in the DSLR business.

    Cheers,
    Alan
     
    Alan Browne, Jun 11, 2006
    #18
  19. RichA

    Jeff Rife Guest

    Alan Browne () wrote in rec.photo.digital.slr-systems:
    Yow. I take it you have a lot of big glass.
    I've probably only got $3,000 or so in 7 lenses but I'm still with you
    on this. Give me a 7D body/control layout with at least some of the
    good features of the A100 (pixel count, dust shaker, etc.) and I might
    be tempted, but anything else is just as you say: a glorified P&S.

    --
    Jeff Rife | "Wheel of morality,
    | Turn, turn, turn.
    | Tell us the lesson
    | That we should learn"
    | -- Yakko, "Animaniacs"
     
    Jeff Rife, Jun 12, 2006
    #19
  20. RichA

    ian Guest

    First time out they are probably testing the water. Whether you get your
    pro spec one will be determined on how well this one sells.
     
    ian, Jun 12, 2006
    #20
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