A camera for taking pictures, comprises a viewfinder masking device having three different format mask configurations; a manual picture-format selector having three different format selection settings which correspond respectively to the three different format mask configurations in order to select any one of the three different format mask configurations; and a default reset for returning the selector to a predetermined one of the three different format selection settings and returning the viewfinder masking device to a corresponding one of the three different format mask configurations, when the selector is in any one of the selection settings that is not the predetermined one, after a picture is taken and before another picture is taken.