In the graphics settings, the description for "View distance" which has a slider for 1-100 is as follows:
Adjusts the distance at which certain objects in the game will no longer be visible. Increasing this will provide a richer and more realistic environment at the expense of performance.
Does that include players or siege weapons? That is the most important to me. If I can see someone at a further distance in PVP it is always advantageous.