A method comprising: receiving an indication associated with an initial observation setup of a set of transmission units of an audiovisual presentation comprising virtual reality audiovisual content, wherein the initial observation setup comprises at least one observation point associated with a three dimensional viewing space region ; receiving an indication associated with an intended behavior of a playback device with respect to the initial observation setup; determining whether a condition associated with the intended behavior of the playback device with respect to the initial observation setup is met; and in response to determining whether the condition associated with the intended behavior of the playback device is met, causing a control signal to be generated, wherein the control signal is associated with a rendering operation of the audiovisual presentation on the playback device , characterised in that the 3D viewing space region comprises a safe viewing space region and a maximum viewing space region where the virtual reality visual content would be responsive to the viewer's translational movement, and a guard range between the safe viewing space region and the maximum viewing space region where the best or fully optimized viewing experience is not guaranteed, wherein the method comprises implementing visual effects in a subset of the audiovisual presentation within the guard range . receiving an indication associated with an initial observation setup of a set of transmission units of an audiovisual presentation comprising virtual reality audiovisual content, wherein the initial observation setup comprises at least one observation point associated with a three dimensional viewing space region ; receiving an indication associated with an intended behavior of a playback device with respect to the initial observation setup; determining whether a condition associated with the intended behavior of the playback device with respect to the initial observation setup is met; and in response to determining whether the condition associated with the intended behavior of the playback device is met, causing a control signal to be generated, wherein the control signal is associated with a rendering operation of the audiovisual presentation on the playback device , receiving an indication associated with an intended behavior of a playback device with respect to the initial observation setup; determining whether a condition associated with the intended behavior of the playback device with respect to the initial observation setup is met; and in response to determining whether the condition associated with the intended behavior of the playback device is met, causing a control signal to be generated, wherein the control signal is associated with a rendering operation of the audiovisual presentation on the playback device , characterised in that the 3D viewing space region comprises a safe viewing space region and a maximum viewing space region where the virtual reality visual content would be responsive to the viewer's translational movement, and a guard range between the safe viewing space region and the maximum viewing space region where the best or fully optimized viewing experience is not guaranteed, wherein the method comprises implementing visual effects in a subset of the audiovisual presentation within the guard range . <EOS>