diff --git a/example/package.json b/example/package.json
index 10634eb9..1d743b86 100644
--- a/example/package.json
+++ b/example/package.json
@@ -22,7 +22,7 @@
     "@angular/platform-browser-dynamic": "^5.0.0",
     "@angular/router": "^5.0.0",
     "core-js": "^2.4.1",
-    "ngx-openlayers": "^0.8.16",
+    "ngx-openlayers": "^0.8.21",
     "rxjs": "^5.5.2",
     "zone.js": "^0.8.14"
   },
diff --git a/example/src/app/raster/raster.component.html b/example/src/app/raster/raster.component.html
index 385cd258..fa3133b1 100644
--- a/example/src/app/raster/raster.component.html
+++ b/example/src/app/raster/raster.component.html
@@ -45,13 +45,13 @@
   <span>Contrast : </span>
   <input type="range" min="-255" max="255"
          [(ngModel)]="contrast"
-         (input)="raster1.instance.changed(); raster2.instance.changed()" />
+         (input)="updateRaster()" />
   <span> ({{ contrast }})</span>
 </div>
 <div class="control">
   <span>Brightness : </span>
   <input type="range" min="-255" max="255"
          [(ngModel)]="brightness"
-         (input)="raster1.instance.changed(); raster2.instance.changed()" />
+         (input)="updateRaster()" />
   <span> ({{ brightness }})</span>
 </div>
diff --git a/example/src/app/raster/raster.component.ts b/example/src/app/raster/raster.component.ts
index 88556999..323a05a9 100644
--- a/example/src/app/raster/raster.component.ts
+++ b/example/src/app/raster/raster.component.ts
@@ -1,4 +1,5 @@
-import { Component } from '@angular/core';
+import {Component, ViewChild} from '@angular/core';
+import {SourceRasterComponent} from 'ngx-openlayers';
 
 interface RasterData {
   brightness: number;
@@ -15,15 +16,16 @@ export class RasterComponent {
   operationType = 'image';
   lib: any = {
     brightness: brightness,
-    contrast: contrast
+    contrast: contrast,
   };
   brightness = 0;
   contrast = 0;
 
   selectLayer = 'osm';
+  @ViewChild(SourceRasterComponent) currentRasterSource;
 
   beforeOperations(event) {
-    let data: RasterData = event.data;
+    const data: RasterData = event.data;
     data.brightness = this.brightness;
     data.contrast = this.contrast;
   }
@@ -35,7 +37,11 @@ export class RasterComponent {
     return imageData;
   }
 
-  afterOperations() { }
+  afterOperations() {}
+
+  updateRaster() {
+    this.currentRasterSource.instance.changed();
+  }
 }
 
 /**