Image circle

The image circle is the mental circle that touches on all four corners of a sensor. It is important to know that an image that hits the sensor through the optics, i.e. the lens, has a round shape. The sensor, however, is rectangular. Thus, the image circle should always be larger than the area of the sensor in order not to “give up” any sensor area and to avoid dark spots at the edges of the image.
Depending on the size and geometric format of the sensor and optics, the image circle can be very different. However, especially when selecting suitable lenses, this size serves as a guide. For optimal image quality, the image circle and sensor area should match well.

The sensor of the X71 camera used in our systems has an image circle of 43 mm.