I'm trying to get a 2d tilemap rendering but somethings not clicking with me about the 2d coordinates...

Here's my basic tilemap class -

public class Map : MonoBehaviour {
public Transform tilePrefab;

public int mapWidth;
public int mapHeight;
public Transform[,] map;

// Use this for initialization
void Start () {
    map = new Transform[mapWidth, mapHeight];

    for (int y = 0; y < mapHeight; y++)
    {
        for (int x = 0; x < mapWidth; x++)
        {
            Transform tile = Instantiate(tilePrefab, new Vector3 (x, y, 0), Quaternion.identity) as Transform;
            tile.parent = transform;
            map[x, y] = tile;
        }
    }
}

But this is rendering the tilemap from the origin -

I want that tilemap to be dynamically centered on the camera like -

What I can't seem to work out is how to dynamically work out the coordinates to move that tilemap so that it's centered in the camera after it has been created.

Any help / pointers to some decent resources would be much appreciated, cheers.