diff --git a/src/picam/picam1.py b/src/picam/picam1.py
index f2182ba..6442fa7 100644
--- a/src/picam/picam1.py
+++ b/src/picam/picam1.py
@@ -36,10 +36,12 @@ class PiCam1(PiCam):
 
     def capture(self, preview: bool = False) -> bytearray:
         # Bytes to hold output buffer
-        out = bytearray()
         bytes_stream = BytesIO()
 
-        if not preview:
+        if preview:
+            out = bytearray(self.preview_resolution[0] * self.preview_resolution[1])
+        else:
+            out = bytearray(self.capture_resolution[0] * self.capture_resolution[1])
             # If preview we'll already have the right resolution
             self.set_camera_resolution(self.capture_resolution)