A viewing apparatus comprising: a headset adapted to be fixed, in a headset donning mode, on, or with respect to, a head of a user; the headset including at least one viewing lens for at least one of the eyes of the user, so as to view a display screen of a mobile computing device, the mobile computing device optionally being a cellphone; a holding case adapted to fixedly hold the mobile computing device and to reversibly attach to the headset; an optical arrangement ((345,342) associated with the holding case and with the headset, and including at least one optical angle modifier and at least one optical splitter; the headset, the holding case, and the optical arrangement (342,345) adapted such that, in a viewing configuration of the donning mode, in which the mobile computing device is inserted in the holding case, a display screen of the mobile computing device faces the at least one viewing lens of the headset; wherein the optical arrangement (345,342) is further adapted to simultaneously establish, in the viewing configuration, a first optical path between the at least one viewing lens of the headset and a camera lens of the mobile computing device; and a second optical path between the display screen of the mobile computing device and the at least one viewing lens of the headset; wherein the at least one optical splitter is optically disposed on the first optical path, between the viewing lens and the at least one optical angle modifier; wherein the at least one optical angle modifier is optically disposed on the first optical path, between the at least one optical splitter and the camera lens; and wherein the at least one optical angle modifier is adapted to modify an angle of incident light received via the at least one optical splitter, and to direct the light towards the camera lens; characterized in that the viewing apparatus further comprises a screen filter optically disposed between the screen of the mobile computing device and the optical splitter, and adapted and oriented to filter at least a portion of low-angle light emanating from the screen in the direction of the optical angle modifier closest to the camera lens, the low-angle light being at most 50°. a headset adapted to be fixed, in a headset donning mode, on, or with respect to, a head of a user; the headset including at least one viewing lens for at least one of the eyes of the user, so as to view a display screen of a mobile computing device, the mobile computing device optionally being a cellphone; a holding case adapted to fixedly hold the mobile computing device and to reversibly attach to the headset; an optical arrangement ((345,342) associated with the holding case and with the headset, and including at least one optical angle modifier and at least one optical splitter; the headset, the holding case, and the optical arrangement (342,345) adapted such that, in a viewing configuration of the donning mode, in which the mobile computing device is inserted in the holding case, a display screen of the mobile computing device faces the at least one viewing lens of the headset; wherein the optical arrangement (345,342) is further adapted to simultaneously establish, in the viewing configuration, a first optical path between the at least one viewing lens of the headset and a camera lens of the mobile computing device; and a second optical path between the display screen of the mobile computing device and the at least one viewing lens of the headset; wherein the at least one optical splitter is optically disposed on the first optical path, between the viewing lens and the at least one optical angle modifier; wherein the at least one optical angle modifier is optically disposed on the first optical path, between the at least one optical splitter and the camera lens; and wherein the at least one optical angle modifier is adapted to modify an angle of incident light received via the at least one optical splitter, and to direct the light towards the camera lens; characterized in that the viewing apparatus further comprises a screen filter optically disposed between the screen of the mobile computing device and the optical splitter, and adapted and oriented to filter at least a portion of low-angle light emanating from the screen in the direction of the optical angle modifier closest to the camera lens, the low-angle light being at most 50°.