Entity info_player_intermission
The info_player_intermission entity comes into effect when you go into the spectator mode. The first image you will see is the one you define via the intermission. Also the podium in single player matches or the final scores in multiplayer matches are shown in front of the defined view.
For this just add an info_player_intermission to the map and connect it to a target_position. The intermission entity now "looks" into the position's direction.
You can also pitch, yaw and roll the destined view by the "angles" key. The default value of this is (0 0 0).
New versions of the Radiant editor can use the pitch, yaw, roll of the 3d camera by opening the Entity Inspector n und selecting the Cam to angles button.
Written by Bliccer