XNA 4.0 SetRenderTarget result in full purple screen

Question

I'm currently making a 2D side-scroller game with XNA for my personal project. My goal for the moment is to have fun with shaders. But I'm actually stuck by the SetRenderTarget(RenderTarget2D) method, I don't understand why once i call it the game gets a full purple screen.

I searched everywhere and I still don't understand where the problem is, but i think its maybe due to my way of beginning the spritebatch.

public void Draw(GraphicsDevice graphics, SpriteBatch spriteBatch, RenderTarget2D mainScene)
    {
        graphics.SetRenderTarget(mainScene);
        graphics.Clear(Color.Black);
        spriteBatch.Begin(SpriteSortMode.Deferred, null, null, null, null, null, _camera.GetViewMatrix(Parallax));

        foreach(Sprite sprite in Sprites)
            sprite.Draw(spriteBatch);

        spriteBatch.End();
        graphics.SetRenderTarget(null);            
    }

Any ideas ? Thanks in advance :)

Answer 1

You are drawing to a RenderTarget not the BackBuffer. When you draw nothing to the BackBuffer it defaults to a purple color. Draw while the RenderTarget is set to null to draw to the BackBuffer which dictates what you see on the screen. RenderTargets are for drawing things off screen.