protected override void OnPaint(PaintEventArgs e)
        {
            base.OnPaintBackground(e);

            float xpos;
            float ypos;

            CalcXYPositions(out xpos, out ypos);
            e.Graphics.TranslateTransform(xpos, ypos);

            DrawImageZoom(e.Graphics);
            _OperationsManager.Paint(this, e);
        }