 		opts =
 			timeout: twoMinsInMs
 		exec args, opts,(err, stdout, stderr)->
+			if err?
+				logger.err err:err, stderr:stderr, sourcePath:sourcePath, "something went wrong converting file to preview"
+			else
+				logger.log  sourcePath:sourcePath, "finished thumbnailing file"
 			callback(err, destPath)	
 
 	preview: (sourcePath, callback)->

		opts =
			timeout: twoMinsInMs
		exec args, opts,(err, stdout, stderr)->
			callback(err, destPath)

			timeout: twoMinsInMs
		exec args, opts, (err, stdout, stderr)->
			timer.done()
			if err?
				logger.err err:err, stderr:stderr, sourcePath:sourcePath, requestedFormat:requestedFormat, "something went wrong converting file"
			else
				logger.log  sourcePath:sourcePath, requestedFormat:requestedFormat, "finished converting file"
			callback(err, destPath)

	thumbnail: (sourcePath, callback)->
