From 5da5271446f1e14eb7bb61e69ad1a0fa9cb4e757 Mon Sep 17 00:00:00 2001
From: "T. E. Pickering" <te.pickering@gmail.com>
Date: Thu, 23 Oct 2025 22:09:28 -0700
Subject: [PATCH] initialize isolist for ellipse fitting

---
 mmtwfs/wfs.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/mmtwfs/wfs.py b/mmtwfs/wfs.py
index 0290e31..344cfe7 100644
--- a/mmtwfs/wfs.py
+++ b/mmtwfs/wfs.py
@@ -1027,6 +1027,7 @@ def vlt_seeing(self, spot, mode, airmass=None):
         with warnings.catch_warnings():
             # ignore astropy warnings about issues with the fitting process...
             warnings.simplefilter("ignore")
+            isolist = []
             # the initial angle seems to matter for getting successful fits so try a set
             for ang in [0, 45, 90, 135, 180]:
                 try: