set effect for imageview in javafx

I have created a frame with some pictures in it. I would like to add a glow effect to the button's in my scence, such that the button's foreground gets brighter on 'mouse over'.

Here is my FXML document:

public class FrameController implements Initializable {
@FXML
private GridPane album;
ImageView im;

/**
 * Initializes the controller class.
 */
@Override
public void initialize(URL url, ResourceBundle rb) {
    // TODO
}    

@FXML
private void mouseEntered(MouseEvent event) {
    System.out.println(event.getSource());
    im = (ImageView) event.getSource();
    Glow selectGlow = new Glow(1.7f);
    im.setOnMouseEntered(new EventHandler<MouseEvent>() {
    
    @Override
    public void handle(MouseEvent event) {
    im.setEffect(selectGlow);
    }
    });
}

}

but i have two problem:

1)It is very slow and sometimes it seems that mouse handler is not called when i am on a picture because effect does not change

2)I do not know which effect should i use in order to make picture darker when mouse enters pictures area

The performance depends on the effect. If you really only want to change the brightness, you could e. g. use ColorAdjust like this:

public class ImageTest extends Application {

    public static void main(String[] args) {
        launch(args);
    }

    @Override
    public void start(Stage primaryStage) {

        primaryStage.setTitle("Hello World!");

        Group root = new Group();

        Image image = new Image("http://upload.wikimedia.org/wikipedia/commons/thumb/4/41/Siberischer_tiger_de_edit02.jpg/320px-Siberischer_tiger_de_edit02.jpg");


        GridPane gridPane = new GridPane();

        gridPane.add(createImageView( image), 0,0);
        gridPane.add(createImageView( image), 1,0);
        gridPane.add(createImageView( image), 0,1);
        gridPane.add(createImageView( image), 1,1);


        root.getChildren().add( gridPane);

        primaryStage.setScene(new Scene(root, 800, 600));
        primaryStage.show();
    }

    private ImageView createImageView( Image image) {

        ImageView imageView = new ImageView(image);

        ColorAdjust colorAdjust = new ColorAdjust();
        colorAdjust.setBrightness(-0.5);

        imageView.addEventFilter(MouseEvent.MOUSE_ENTERED, e -> {

            imageView.setEffect(colorAdjust);

        });
        imageView.addEventFilter(MouseEvent.MOUSE_EXITED, e -> {
            imageView.setEffect(null);
        });

        return imageView;
    }
}