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  • Source Four Focal Length, Pattern Size and Image Diameters


    Question

    What Size Patterns Do Source Fours Use and What Are The Image Diameters and Focal Lengths?


    Answer

    Source Four uses "A" and/or "B" size patterns and Source Four jr uses "M" size patterns.

    TypeOuter DiameterMax Image Diameter
    A3.93"/100mm2.95"/75.0mm
    B3.38"/86mm2.53"/64.5mm
    M2.57"/65.5mm1.94"/49.5mm


    The gate size in a Source Four is 3.12"/79.24mm.
    The gate size in a Source Four jr is 2.15"/54.61mm.

     

    Focal Length Source Four:

    90 degree

    2.13"/54.1mm

    70 degree

    2.67"/67.82mm

    50 degree

    3.3"/83.82mm

    36 degree

    4.8"/121.92mm

    26 degree

    6.8"/172.72mm

    19 degree

    9.3"/236.22mm

    14 degree

    11.05"/280.67mm

    10 degree

    17.8"/452.12mm

    5 degree

    25.5"/647.70mm



    Focal Length Source Four jr:

    26 degree4.66"/118.3mm
    36 degree3.27"/83.18mm
    50 degree2.33"/59.18mm


    FixtureActual Field Angle (per 7/2003 testing)Lens Focal Length
    S4 15-3016.2° minimum278mm
    31.3° max141mm
    S4 25-5026.9° minimum166mm
    49.0° max87mm