These are usually wide-angle lenses with fixed aperture, and cameras with these lenses generally use a viewfinder for composition. Especially suitable are fixed-focus lenses for low-resolution CCD cameras as found in webcams, surveillance cameras and camera phones, because the low resolution of the image sensor allows a loose focusing on the CCD without noticeable loss of image quality. This makes a bigger circle of confusion and smaller hyperfocal distance. Special-purpose cameras such as the Agiflite  are used for situations like aerial photography from aircraft. Because the ground is far from the camera, focus adjustment is not necessary. Light-field cameras use fixed-focus lenses, since the focus can be set when the picture is displayed. For 35 mm cameras, some superwide fixed-focus lenses have been made.