KeystoneKorrektur

KeystoneKorrektur, often referred to as keystone correction, is a feature found in projectors that allows users to adjust the image geometry. When a projector is placed at an angle to the screen, the projected image can appear distorted, resembling a trapezoid rather than a rectangle. This distortion is known as keystone effect. KeystoneKorrektur digitally compensates for this angle, effectively straightening the image and restoring its rectangular shape.

The process typically involves adjusting vertical and sometimes horizontal keystone settings. Vertical keystone correction is the most common, as projectors are often placed below or above the center of the screen. Some projectors also offer horizontal keystone correction, which is useful when the projector is positioned off-center to the left or right of the screen. The correction is achieved by stretching or compressing pixels in specific areas of the image.

While keystone correction is a convenient feature for aligning the image without physically repositioning the projector, it's important to note that excessive correction can lead to a reduction in image sharpness and brightness. This is because the digital manipulation of pixels can introduce artifacts. For the best possible image quality, it is generally recommended to position the projector as squarely as possible to the screen and use keystone correction only minimally to correct for minor misalignments. Advanced projectors may offer more sophisticated digital lens shift or warping capabilities that provide superior image correction with less impact on image quality.