diff --git a/MMM-ImageSlideshow.js b/MMM-ImageSlideshow.js
index ca1dbd5..3efc8f7 100644
--- a/MMM-ImageSlideshow.js
+++ b/MMM-ImageSlideshow.js
@@ -34,6 +34,8 @@ Module.register("MMM-ImageSlideshow", {
         validImageFileExtensions: 'bmp,jpg,gif,png',
 		// a delay timer after all images have been shown, to wait to restart (in ms)
 		delayUntilRestart: 0,
+		//opacity of the image
+		opacity: 1.0
 	},
     // load function
 	start: function () {
@@ -141,6 +143,9 @@ Module.register("MMM-ImageSlideshow", {
 						styleString += 'width:' + this.config.fixedImageWidth + 'px;';
 					if (this.config.fixedImageHeight != 0)
 						styleString += 'height:' + this.config.fixedImageHeight + 'px;';
+					// if opacity of image changed
+					if(this.config.opacity != 1.0)
+					styleString += 'opacity:' + this.config.opacity;
 					// if style string has antyhing, set it
 					if (styleString != '')
 						image.style = styleString;
diff --git a/README.md b/README.md
index 706eb75..9c68463 100644
--- a/README.md
+++ b/README.md
@@ -111,5 +111,13 @@ The following properties can be configured:
 				<br>This value is <b>OPTIONAL</b>
 			</td>
 		</tr>         
+		<tr>
+			<td><code>opacity</code></td>
+			<td>Opacity of the image. Ranged 0.0 to 1.0.<br>
+				<br><b>Example:</b> <code>0.5</code>
+				<br><b>Default value:</b> <code>1.0</code>
+				<br>This value is <b>OPTIONAL</b>
+			</td>
+		</tr>         
     </tbody>
 </table>