Setting Default Custom Background to My Theme

So I am trying to create a Theme which incorporates the Bootstrap Framework which I have managed to get working now and I have begun to start styling the theme.

I have run in to an issue though tonight. I want the theme to have a Custom Background as default which is an Fixed, No-Repeat, Centered Image. I have tried many way through the functions.php file to get the Custom Background to load but to no avail..

Here is the latest snipped of code :

// Register Theme Features
function custom_theme_features()  {

	// Add theme support for Custom Background
	$background_args = array(
		'default-color'          => 'ffffff',
		'default-image'          => 'http://www.djbroadhurst.co.uk/templates/ecommerce/wordpress/wp-content/themes/wpbootstrap/images/background.jpg',
		'default-repeat'         => 'no-repeat',
		'default-position-x'     => '',
		'wp-head-callback'       => '',
		'admin-head-callback'    => '',
		'admin-preview-callback' => '',
	);
	add_theme_support( 'custom-background', $background_args );
}

// Hook into the 'after_setup_theme' action
add_action( 'after_setup_theme', 'custom_theme_features' );

If anyone can help me with this it would be wonderful. I am really struggling. I am not very good with php in the first place but managing to get my way around most the other sections.

So once again I would like that image to be a Fixed / No-Repeat / Centered Background Image by Default when the person uses the theme but then still be able to customise it via the Customiser.