Could you actually see photos made from RAW files?

Discussion in 'Digital Photography' started by aniramca, May 30, 2009.

  1. aniramca

    Eric Stevens Guest

    Not so. The sensor stores volts. The RAW file maps this in 12 or 14
    bit patterns. Some transformation has clearly taken place. Nor is it
    necessarily compressed and, if compression has taken place it need not
    be lossless.
    My original proposition was that there is a one to one correspondence
    between the source image (that which is projected onto the sensor by
    the lens) and data which is stored in the RAW file. Its not possible
    that any single RAW file could be produced by more than one sensor
    image.



    Eric Stevens
     
    Eric Stevens, Jun 1, 2009
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  2. aniramca

    Eric Stevens Guest

    Note that it refers to NEF files which have been modified by Nikon
    applications. i.e. it deals not just with 'out of the camera' RAW
    files.



    Eric Stevens
     
    Eric Stevens, Jun 1, 2009
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  3. aniramca

    Guest Guest

    and where is that noted?? hint - you're wrong (again).
     
    Guest, Jun 2, 2009
  4. aniramca

    tony cooper Guest

    I must be missing a step. I did that, but I can't work on a smart
    object without rasterizing it. If I duplicate the original layer, do
    something to it in PS, and then return to the raw editing mode, I can
    change the .dng, but the duplicated layer is not affected by the
    change.

    I don't think I explained that very well.
     
    tony cooper, Jun 2, 2009
  5. aniramca

    Eric Stevens Guest

    With all these changes to its form, the original data has clearly been
    transformed. This does not mean that its meaning has been changed.
    Merely that its form has been changed.
    Your turn now. Have a look at what I am trying to say about the
    meaning of transformation. 1/4 = 0.25



    Eric Stevens
     
    Eric Stevens, Jun 2, 2009
  6. aniramca

    Eric Stevens Guest

    I note you removed the link which would show I was correct.

    See http://www.nikonimglib.com/nefcodec/

    * Fixed an issue that caused a message stating that the image was
    corrupt to be displayed when a photograph for which the
    “Landscape†or “Portrait†Picture Control had been selected
    using ViewNXâ„¢ was displayed in Windows Photo Gallery on a
    computer to which optional Picture Controls had not been
    installed.

    i.e. If you use ViewNX to amend the file by selecting “Landscape†or
    “Portrait†the file might be reported as corrupt in Windows Photo
    Gallery.

    * If the user attempted to use Windows Photo Gallery to e-mail
    an NEF file edited in Capture NX 2â„¢, the JPEG attachment would
    be cropped to 1,280 × 1,024 pixels. This issue has been
    resolved.

    i.e. this clearly refers to a NEF file which has been edited out of
    the camera.



    Eric Stevens
     
    Eric Stevens, Jun 2, 2009
  7. aniramca

    Guest Guest

    it's exactly the same as how you would normally work with raw, except
    that you can double-click the image and go back to camera raw to make a
    change. there's no need to duplicate the original layer.

    have you worked with smart filters? it's the same concept.
     
    Guest, Jun 2, 2009
  8. aniramca

    Guest Guest

    you didn't specify whether you were referring to osx or windows so i
    snipped both. either way, it doesn't show what you think it does.
    that doesn't rule out that it can still process nef file direct from
    the camera. in other words, it will handle *both* a nef that was
    processed in nx and one direct from the camera.
     
    Guest, Jun 2, 2009
  9. aniramca

    Guest Guest

    so he keeps the border pixels. that doesn't negate what i said.
     
    Guest, Jun 2, 2009
  10. aniramca

    Eric Stevens Guest

    This is why we have been arguing. See the definitions of
    Transformation at http://www.thefreedictionary.com/transformation

    In the particular context the ones that apply are:

    3. Mathematics
    a. Replacement of the variables in an algebraic expression by
    their values in terms of another set of variables.
    b. A mapping of one space onto another or onto itself.
    4. Linguistics
    a. A rule that systematically converts one syntactic form or
    form of a sentence into another.
    b. A construction or sentence derived by such a rule; a
    transform.

    It is the systematic conversion which is at the heart of it all.



    Eric Stevens
     
    Eric Stevens, Jun 2, 2009
  11. aniramca

    Eric Stevens Guest

    Are you really saying that a given RAW data file can be created by
    more than one image?



    Eric Stevens
     
    Eric Stevens, Jun 2, 2009
  12. aniramca

    Eric Stevens Guest

    I'm trying to get through to others what is wrong with what you have
    been doing to me. The only difference is that I confined myself to
    deleting individual words from the one paragraph and then I pointed
    out what I had done. You - you have been deleting whole paragraphs so
    as to completely change the sense of what we have been arguing about.
    You then compound matters by not even indicating where or that you
    have snipped. To finish it off, you start preaching about netiquette!
    Bullshit. And, as you have already said, you have been round Usenet
    more than long enough to know better.
    Bullshit. It was the norm when you hung around sci.archaeology. I
    agree it is not common here but people don't normally snip out
    numerous segments of the article to which they have been responding in
    the way that you have been doing it.
    Let's get this clear. Are you saying that many different images
    projected onto the sensor can result in the same RAW data file?
    I know what an analog device is. The wells in the sensor count
    electrons as a proxy for photons. You can't have fractional electrons.
    You can't have fractional photons. You must have integer values. It
    cannot be an an analog device.
    You are referring to 'firmware' as though it was 'hardware'. Yet Nikon
    can program the camera to behave differently so some software/firmware
    must be involved.
    .... but that's where we came in. You wrote:

    "That's what a camera raw file (the so called RAW format) is... a
    pile of parts that you can build an image from, and while the
    photographer may have had one specific image in mind when that
    pile of data was saved, it can be restructured to make a lot of
    different images too."

    .... and I responded:

    "Floyd, I suspect you have been smoking something which is not
    good for you. Subject to statistical error limitations, there is a
    one to one correspondence between the source image and the
    RAW file. One can be converted to the other using the rules
    inherent in the camera's software. The data in the RAW file can't
    be restructured to make a different image without changing the
    data."

    Basically what I said was that what I just quoted you as saying is a
    'nonsense idea'.
    Unless you can explain how a particular electronic charge from the
    sensor can be saved _in_its_original form_ on a Compact Flash card
    then you have to accept that the data from the sensor is transformed
    before it is saved.
    You can track back through the logic and determine the original state
    of the sensor which gave rise to the particular Raw data file. Mind
    you, You would have to know Nikon's original transformation algorithm
    before you could work it backwards. I wouldn't like to have to do it.
    I invite you to do so.
    Well that's a good wriggle but if you read back above you will find
    there are many points you have to answer. I would particularly like a
    clear explanation of how there can be multiple images on the sensor
    that could produce exactly the same data set. After all, this is where
    we came in.



    Eric Stevens
     
    Eric Stevens, Jun 2, 2009
  13. aniramca

    Eric Stevens Guest

    You are quibbling. Whether you call it data encoding or not, it is a
    transformation of the data. And no, I'm not trying to say that it
    changes the image although in some cases that might happen.


    Eric Stevens
     
    Eric Stevens, Jun 2, 2009
  14. aniramca

    Eric Stevens Guest

    You keep trying to change the subject. Of course the RAW data can be
    used to produce multiple images but not if the image you are referring
    to is the source image on the sensor which you can recreate by running
    the RAW data backwards through the original transformation algorithm.
    I'd love you to explain how that can be done.



    Eric Stevens
     
    Eric Stevens, Jun 2, 2009
  15. aniramca

    Eric Stevens Guest

    So you keep saying. Please explain. This is at the heart of our
    argument.



    Eric Stevens
     
    Eric Stevens, Jun 2, 2009
  16. aniramca

    Eric Stevens Guest

    So? It was the possibility of out of camera editing of the NEF file I
    was pointing to.



    Eric Stevens
     
    Eric Stevens, Jun 2, 2009
  17. aniramca

    Chris H Guest

    Well at the risk of getting tedious I can start posting the licenses for
    the Public domain software on the CD
    No it is the individual pieces of software.
     
    Chris H, Jun 2, 2009
  18. aniramca

    Bob Larter Guest

    With Canons, I believe that at least some sort of noise reduction is
    done at that stage. I expect that it's true of other brands as well.
     
    Bob Larter, Jun 2, 2009
  19. aniramca

    Bob Larter Guest

    Nifty! I haven't installed CS4 yet, but that feature alone might make it
    worth the upgrade.
     
    Bob Larter, Jun 2, 2009
  20. It seems that some camera makers don't consider doing some
    "improvements" to the RAW data from the sensor as "screwing around
    with" :)
     
    Chris Malcolm, Jun 2, 2009
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