diff --git a/imagekit/cachefiles/__init__.py b/imagekit/cachefiles/__init__.py
index 974b643..e606e18 100644
--- a/imagekit/cachefiles/__init__.py
+++ b/imagekit/cachefiles/__init__.py
@@ -27,10 +27,12 @@ class ImageCacheFile(BaseIKFile, ImageFile):
         """
         self.generator = generator
 
-        name = name or getattr(generator, 'cachefile_name', None)
         if not name:
-            fn = get_by_qname(settings.IMAGEKIT_CACHEFILE_NAMER, 'namer')
-            name = fn(generator)
+            try:
+                name = generator.cachefile_name
+            except AttributeError:
+                fn = get_by_qname(settings.IMAGEKIT_CACHEFILE_NAMER, 'namer')
+                name = fn(generator)
         self.name = name
 
         storage = storage or getattr(generator, 'cachefile_storage',
diff --git a/imagekit/specs/__init__.py b/imagekit/specs/__init__.py
index 969dcf3..a8fa742 100644
--- a/imagekit/specs/__init__.py
+++ b/imagekit/specs/__init__.py
@@ -82,6 +82,8 @@ class ImageSpec(BaseImageSpec):
 
     @property
     def cachefile_name(self):
+        if not self.source:
+            return None
         fn = get_by_qname(settings.IMAGEKIT_SPEC_CACHEFILE_NAMER, 'namer')
         return fn(self)