不能让jssor jQuery滑块在全屏上显示大图像时褪色

我什么都试过了，还是不行。我试着全屏显示图像。图像被替换，但没有渐变效果。

图片很大(500kb)。任何建议吗?

var _SlideshowTransitions = [
            { 
            $Duration: 1000, 
            //$Delay: 300, 
            // $Cols: 8, 
            // $Rows: 4, 
            // $Top: true, 
            // $Right: true, 
            // $Bottom: true, 
            // $Left: true, 
             $Fade: true,
            //$SlideOut: true, 
            // $Assembly: 2049, 
            // $Easing: $JssorEasing$.$EaseOutQuad, 
            // $Formation: $JssorSlideshowFormations$.$FormationStraightStairs 
            // $Formation: $JssorSlideshowFormations$.$FormationStraightStairs 
            }
];
var _options = {
                $PauseOnHover: 0,
                $ArrowKeyNavigation: true,
                $AutoPlay: true,                                    //[Optional] Whether to auto play, to enable slideshow, this option must be set to true, default value is false
                $SlideshowOptions: {                                //[Optional] Options to specify and enable slideshow or not
                    $Class: $JssorSlideshowRunner$,                 //[Required] Class to create instance of slideshow
                    $Transitions: _SlideshowTransitions            //[Required] An array of slideshow transitions to play slideshow
                }
};

jssor_slider = new $JssorSlider$("slider1_container", _options);