If the projector is not aligned perpendicular to the screen, the projected image is significantly distorted. This is due to a physical phenomenon that can lead to impressive visual effects. But when a distortion is unwanted, an artificial distortion can be created in the artwork on the gobo which compensates the original distortion. Now the projected images appears undistorted in the eyes of the viewer. This procedure is called keystone correction, named after the trapezoidal keystone in an arch. Keystone correction can compensate distortion in the horizontal and vertical axis, up to a deviation of 45°!
Without keystone correction
With keystone correction: The pre-distorted artwork on the gobo makes the projected image appear correctly.
Is a keystone correction required for your projection? Please inform us when ordering. You will receive from us a measurement gobo whose projected image must be photographed on site. Your digital photo is the basis for manufacuring the corrected gobo.