diff --git a/source/java/org/alfresco/repo/thumbnail/ThumbnailRenditionConvertor.java b/source/java/org/alfresco/repo/thumbnail/ThumbnailRenditionConvertor.java
index 235914b22d..88071a4dd4 100644
--- a/source/java/org/alfresco/repo/thumbnail/ThumbnailRenditionConvertor.java
+++ b/source/java/org/alfresco/repo/thumbnail/ThumbnailRenditionConvertor.java
@@ -22,6 +22,7 @@ import java.io.Serializable;
 import java.util.HashMap;
 import java.util.Map;
 
+import org.alfresco.model.ContentModel;
 import org.alfresco.repo.content.transform.magick.ImageResizeOptions;
 import org.alfresco.repo.content.transform.magick.ImageTransformationOptions;
 import org.alfresco.repo.content.transform.swf.SWFTransformationOptions;
@@ -130,7 +131,12 @@ public class ThumbnailRenditionConvertor
     {
         Map<String, Serializable> parameters = new HashMap<String, Serializable>();
         
+        // All TransformationOptions-based renditions are considered to be "thumbnails".
+        // Therefore they should be created with a node type of cm:thumbnail
+        parameters.put(RenditionService.PARAM_RENDITION_NODETYPE, ContentModel.TYPE_THUMBNAIL);
+
         // parameters common to all transformations
+        
         putParameterIfNotNull(AbstractRenderingEngine.PARAM_SOURCE_CONTENT_PROPERTY, transformationOptions.getSourceContentProperty(), parameters);
         putParameterIfNotNull(AbstractRenderingEngine.PARAM_TARGET_CONTENT_PROPERTY, transformationOptions.getTargetContentProperty(), parameters);
         putParameterIfNotNull(RenditionService.PARAM_DESTINATION_NODE, transformationOptions.getTargetNodeRef(), parameters);
diff --git a/source/java/org/alfresco/repo/thumbnail/ThumbnailServiceImpl.java b/source/java/org/alfresco/repo/thumbnail/ThumbnailServiceImpl.java
index df4641cc57..6ef22c9c8d 100644
--- a/source/java/org/alfresco/repo/thumbnail/ThumbnailServiceImpl.java
+++ b/source/java/org/alfresco/repo/thumbnail/ThumbnailServiceImpl.java
@@ -430,7 +430,6 @@ public class ThumbnailServiceImpl implements ThumbnailService
         // Add the other parameters given in this method signature.
         params.put(AbstractRenderingEngine.PARAM_SOURCE_CONTENT_PROPERTY, contentProperty);
         params.put(AbstractRenderingEngine.PARAM_MIME_TYPE, mimetype);
-        params.put(RenditionService.PARAM_RENDITION_NODETYPE, ContentModel.TYPE_THUMBNAIL);
 
         // Set the parameters on the rendition definition.
         definition.addParameterValues(params);
diff --git a/source/java/org/alfresco/repo/thumbnail/ThumbnailServiceImplTest.java b/source/java/org/alfresco/repo/thumbnail/ThumbnailServiceImplTest.java
index 3f4f6de73a..7ad7e3116e 100644
--- a/source/java/org/alfresco/repo/thumbnail/ThumbnailServiceImplTest.java
+++ b/source/java/org/alfresco/repo/thumbnail/ThumbnailServiceImplTest.java
@@ -261,8 +261,14 @@ public class ThumbnailServiceImplTest extends BaseAlfrescoSpringTest
         NodeRef thumbnail1 = this.thumbnailService.createThumbnail(jpgOrig, ContentModel.PROP_CONTENT,
                     MimetypeMap.MIMETYPE_IMAGE_JPEG, imageTransformationOptions, "small");
 
+        // Thumbnails should always be of type cm:thumbnail.
+        assertEquals(ContentModel.TYPE_THUMBNAIL, nodeService.getType(thumbnail1));
+
         // Update the thumbnail
         this.thumbnailService.updateThumbnail(thumbnail1, imageTransformationOptions);
+        
+        // ALF-2047. Thumbnails were changing to type cm:content after update.
+        assertEquals(ContentModel.TYPE_THUMBNAIL, nodeService.getType(thumbnail1));
     }
 
     public void testGetThumbnailByName() throws Exception