diff --git a/lib/bunyan.js b/lib/bunyan.js
index c38f102..2754eba 100644
--- a/lib/bunyan.js
+++ b/lib/bunyan.js
@@ -829,15 +829,17 @@ function mkLogEmitter(minLevel) {
             if (args[0] instanceof Error) {
                 // `log.<level>(err, ...)`
                 fields = {
-                    // if a serializer is defined for err use it else fallback on the default serializer
-                    err: log.serializers.err ? log.serializers.err(args[0]) : Logger.stdSerializers.err(args[0])
+                    // Use this Logger's err serializer, if defined.
+                    err: (log.serializers.err
+                        ? log.serializers.err(args[0])
+                        : Logger.stdSerializers.err(args[0]))
                 };
                 excludeFields = {err: true};
                 if (args.length === 1) {
                     msgArgs = [fields.err.message];
                 } else {
                     msgArgs = Array.prototype.slice.call(args, 1);
-                }                
+                }
             } else if (typeof (args[0]) !== 'object' && args[0] !== null ||
                        Array.isArray(args[0])) {
                 // `log.<level>(msg, ...)`