The mirror’s diameter determines its image-forming capabilities; larger mirrors can produce both real and virtual images regardless of focal point position.

The mirror’s curvature determines its ability to produce both real and virtual images; concave mirrors with positive focal lengths can produce both types depending on object position relative to the focal point.

The mirror’s reflectivity determines its ability to form different image types; highly reflective mirrors can produce both real and virtual images independent of focal point.

The mirror’s thickness is the key factor; thicker mirrors can produce both real and virtual images, while thin mirrors are limited to one type, regardless of focal point.