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  1. #1 Preventing negative pixel values in renders 
    Senior Member Simon Dunne's Avatar
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    I have a shot that is from deep black (night scene) to full highlight (neon light) that i'm scaling from 8k to 4k in ACES Linear EXR. If i select this option in red cine X, all is good. If i use other software to do this render, i get negative pixel values. Is this feature part of the RedCine X software only, or is there something in the SDK that can be turned on by other vendors also to fix this issue?

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  2. #2  
    Senior Member Simon Dunne's Avatar
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    Anyone at Red? Graeme? RC-X team???
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  3.   This is the last RED TEAM post in this thread.   #3  
    There's a specially written scaler in RCX. If you want other software to scale like this in linear light, they would need to write their own special scaler to achieve it. The other "trick" is to convert to log, scale, and then back to linear light.

    Graeme
    www.red.com - 8k Digital Cinema Camera
    Science enables stories. Stories drive science
    IPP2, Image Processing, Colour Science and Demosaic Algorithms
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  4. #4  
    Senior Member Simon Dunne's Avatar
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    Thanks Graeme.
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  5. #5  
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    softclip shadows in Baselight, Nucoda & Resolve, at the start of a stack/layers/node tree when needed works well on RED or Arri RAW
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  6. #6  
    Quote Originally Posted by Dermot Shane View Post
    softclip shadows in Baselight, Nucoda & Resolve, at the start of a stack/layers/node tree when needed works well on RED or Arri RAW
    Yeah but no need to clip.

    :)
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  7. #7  
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    if you are just clipping negitive values and nothing more... then nothing is lost that you don't want lost...
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  8. #8  
    Those data values are just one part of manifestation of a chosen principle.

    Pill doesn't remove the health hazard. :)
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  9. #9  
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    reality -VS- theory


    reality is i don't want negitive pxiels
    reality is i can clip them easly, reliably, cleanly, quickly and move on to digging out the ultimate awesome of the image and making it shine

    without negitive pixels showing

    theory? ehhhhhh......
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  10. #10  
    Quote Originally Posted by Dermot Shane View Post
    reality -VS- theory


    reality is i don't want negitive pxiels
    reality is i can clip them easly, reliably, cleanly, quickly and move on to digging out the ultimate awesome of the image and making it shine

    without negitive pixels showing

    theory? ehhhhhh......
    Reality:

    - pipeline screws up the image
    - needs fiddling to compensate
    - fiddling doesn't compensate for all that is screwed
    - no need to fiddle to compensate if it isn't screwed in the first place

    Theory ?

    :)
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    Analog > Camera feel optimization http://omeneo.com
    Digital > Camera performance optimization http://omeneo.com/primers

    imdb


    "Como delfines en el fondo del oceano
    volamos por el universo incentivados por la esperanza"

    "L'esperanza", Sven Väth
    "It's a poor sort of memory that only works backwards"
    Jung/ Carol
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