Calculate the projected gobo size at any throw distance, or find what throw distance you need for a target projection size. Works for all standard gobo fixture types and holder sizes.
Calculate mode
Fixture — select a preset or enter custom
ETC Source Four
Various lenses
B-size gobo
19 deg lens
fl: 265mm
Narrow spot
26 deg lens
fl: 200mm
Standard spot
36 deg lens
fl: 145mm
Medium
50 deg lens
fl: 107mm
Wide
Custom fixture
Enter below
Any type
From fixture or lens spec sheet
Please select a fixture, enter focal length, and fill in the required field.
Projected gobo diameter
0 ft
0x
Magnification ratio
0
Projected area (sq ft)
0ft
Throw distance
Projection diagram
Projected size at multiple distances
DistanceProj diamProj areaMagnif.Sharpness
Fixture focal length
Gobo holder / image size
Throw distance
Magnification (throw/fl)
Projected diameter
Projected area
Sharpness note
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