All Things Color for Film and Digital Cinema
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Posts Tagged ‘perception’

iRiS S3D Stereo Base and Disparity Calculator Released

The S3D Base and Disparity Calculator is now officially released on the Android Market.

The S3D Calculator is divided into three Main Screens.

Navigating between the screens is performed by swiping the current page with a horizontal finger gesture.

  1. Initial Simple Base Calculation
  2. Base and Disparity Evaluation and adjustment
  3. Disparity Overview and Analysis

Simple Base Calc

Input Options Include:

  • Camera
  • Camera Active Area
  • Lens
  • Screen Size
  • Screen Resolution
  • Parallax Target
  • Distance Measurement Metric (Meters or Feet)

Base and Disparity Evaluation and adjustment

Disparity overview and analysis

Output Data Includes:

    • Base (inter occular Distance)
    • Field of View
    • Angle of View
    • Total Pixel Parallax
    • Total screen Parallax %
    • Total Screen Parallax (mm)
      • Positive Parallax
      • Negative Parallax
    • Zoom Required
    • Post Convergence Required

    Regards,

    Adrian


    Color Blindness – An amazing experiment –

     

    Today I performed an interesting yet simple experiment.

     

    Marcie - Color Test

    Marcie - Color Test - Fig A

     

    Regarding the LAST POST ON COLOR BLINDNESS I began pondering what an emulation of Color Blindness would look to to a person with such a “visually challenged color perception”.

    As a test I invited two colleges to view an image both as natural color original and as a emulation of Color Blindness.

    Here is the website I used to view the color emulation.

    http://www.vischeck.com/vischeck/vischeckImage.php

    Both images looked near identical to each viewer.

    BUT here is the amazing bit. 

    Using a Macbeth color chart Fig.B as a test, I then asked my friends to label the colors they saw.

    Once again to their eyes the two images were ‘the same’ in color…….

     

    Macbeth Test

    Macbeth Test - Fig .B

    No Macbeth  Name           Red/Green Deficient Name A      Red/Green Deficient Name B      
    1 dark skin Dark Chocolate     Brown      
    2 light skin Skin     Tan      
    3 blue sky Light Blue     Light Blue      
    4 foliage Olive Green     Green      
    5 blue flower Light Blue     Light Blue      
    6 bluish green Washed out green     Tan      
    7 orange Terra-cotta     Light Green      
    8 purplish blue Ultramarine     Purple      
    9 moderate red Red Brick     green      
    10 purple Night Sky      Purple      
    11 yellow green Ochre Yellow     Yellow      
    12 orange yellow Sunday Latte     Orange OR Green      
    13 blue Meadow Morning     Blue      
    14 green UltraMarine     Green      
    15 red Brick Red     Green      
    16 yellow Yellow Ochre     Yellow      
    17 magenta Fuchsia – Lilac     Pink      
    18 cyan Light Blue     Light Blue      
    19 white Polar Scape            
    20 neutral 8 Polar Scape 2            

    Friend A interestingly noted wearing Polarized lenses made colors more intense and therefor more distinguishable.

    Doubly interesting was the fact that Friend A  really liked 3D movies as the colors became more intense. I wonder if this is because the eye is being given two distinct references of polarized spectral information to help distinguish the colors.

    I found it amazing that both friends saw the Pink in the aparently Grey patch on line 3 of the simulation Macbeth Chart. It seems almost identical to the grey patch below it. Anecdotally, Friend B told me a story about ordering a new grey kitchen bench a while back. He was mortified on coming home one day to find his new pink kitchen bench!

     

    Adrian Hauser


    Color Blindness….. and color fatigue

     

    An image from the ishihara test for color blindness

    An image from the ishihara test for color blindness

    Color Blindness and color fatigue has been the cause of quite a few conundrums in the grading suite.

    We have all debated with friends, at some point in our lives, the perception of color between each other. “Do you see the blue of the sky the same way I do?” Someone who has been color blind all their lives takes their perception of color as gospel. 

    What’s interesting is when grading a project over a few hours without a break or watching a feature film your internal reference point of what is a correct Balanced Image easily shifts. Technically it only takes 40 minutes for ones Color reference to become ‘reset’, taking on what is presented to you as the new correct reference. In a dark theatre without any external color reference point this is very easy. In this way I find TV grading and feature film grading two quite different beasts. In a darkened theatre our perception of subtle  changes in dark tones is much more than that of a typical television viewing environment where traditionally images are ‘pumped’ to jump off the screen.  

    With this in mind can one be trained to be temporarily color blind in 40 mins?

    I am currently making up some look up tables that emulate different color vision deficiencies. I’d love to use them some day in a film where perhaps one of the characters is color blind.

    An interesting site is this one where you can type in a web address and it will show you how that page or image is percieved by someone deficient in say, Red/Green color.

    Here is the site to go to to check your color vision.

    Ishihara Test

    Adrian