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

iRiS Stereoscopic Base and Disparity Calculator – 1.1.0 Update – Introducing the Roundness Factor

The Stereoscopic Base and Disparity Calculator 1.1.0 for the Android OS has just been updated and introduces a new base calculation measured around the perceived on-screen Roundness or depth of an image.

The new option allows the user to either :

  • Calculate the camera base separation using a predetermined target parallax amount
  • Calculate the camera base separation to a “Roundness Factor” of 1.0.

The Roundness Factor represents the factorial difference in depth between the photographed scene and the resultant projected 3D scene.

It is generally referred as a factor because ideally one would want to capture and project the same depth representation of photographed object, thus having a factor of 1.0.    IE: Physical scene depth/perceived 3D on-screen depth.

If the Roundness Factor is less than 1.0 then for example a round sphere will appear flat and compressed. It will have lost is dimensionality.

If the Roundness Factor is greater than 1.0 then the same sphere will appear stretched or extruded on the Z depth plane.

Consider dimensionality in filming the close-up of someones strong angular face. Captured with perfect roundness the 3D on-screen projected face will feel volumetric and proportionately correct. If the “Roundness Factor” starts getting too high the persons head and nose will begin to feel stretched toward the viewer, which is not such a flattering look.  In this sense it is better to err on the side of a factor less than 1.0.

The effect of Roundness is related very closely to Lens selection. A longer focal length lens will have a much greater impact on roundness and Parallax as the base separation in altered. On a 75mm Lens it takes only small changes in Base distance to make quite large differences in background parallax and therefor depth.   Additionally sensor size is quite an important factor to consider as the resulting 35mm Lens equivalents could be a lot higher than you think.

As always it is recommended to test Lens/Sensor configs as much as possible before entering any project.


iRiS S3D StereoScopic Base and Disparity Calc – new Skin Released

S3D Calc New Skin - template

New skin released with a few UI improvements.


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



    s3d stereoscopic Base and parallax / divergence calculator for Android

    ScreenShots from forth coming s3D Base and Parallax Calculator for Android.

    S3D Stereoscopic Screen Parallax / Disparity Calculator

    v1.04 Excel template of my S3D Screen Parallax Calculator.

    It will end up as an OSX app and a Android Mobile Phone Application in the coming weeks.

    Measures Positive and Negative Pixel Parallax of a Stereo Scene on a given Screen Size.


    • Camera Base
    • Focal Length
    • Near Distance
    • Far Distance
    • Focal Distance
    • Sensor Size
    • Projection Ratio
    • Projection Size
    • Projection Resolution
    • Floating Windows