diff --git a/scripts/export_camera_profile.py b/scripts/export_camera_profile.py
index 12f4f84..81b9095 100755
--- a/scripts/export_camera_profile.py
+++ b/scripts/export_camera_profile.py
@@ -40,15 +40,21 @@ except ImportError:
     sys.exit("vmbpy not installed - see the header of this file")
 
 # Recipes are ordered: binning changes the sensor geometry, and the throughput
-# limit caps the frame rate, so both come before the rate is set. A feature the
-# camera does not have is reported and skipped, not fatal: the fleet runs several
-# Alvium generations and their feature vocabularies differ.
+# limit caps the frame rate, so both come before the rate is set. Frame
+# triggering is turned off first: the host streams free-running frames and never
+# sends a trigger, and a camera that boots with it on (a legacy tower's, whose
+# old program triggered by software) delivers nothing - and keeps its frame rate
+# read-only - until it is off. A feature the camera does not have is reported
+# and skipped, not fatal: the fleet runs several Alvium generations and their
+# feature vocabularies differ.
 RECIPES = {
     # Daylight. 2x2 binning is not optional at 10 Hz: unbinned RGB8 on a 16 MP
     # sensor is a 48 MB frame, which is both over the USB ceiling in
     # known-issues #19 and far too slow to reach 10 fps under any throughput
     # limit this camera offers.
     "standard": [
+        ("TriggerSelector",            "FrameStart"),
+        ("TriggerMode",                "Off"),
         ("BinningHorizontal",          2),
         ("BinningVertical",            2),
         ("PixelFormat",                "RGB8"),
@@ -67,6 +73,8 @@ RECIPES = {
     # Night: 1 Hz, long exposures, more gain allowed, noise over motion blur,
     # and the status LED off so it cannot contaminate a long exposure.
     "night": [
+        ("TriggerSelector",            "FrameStart"),
+        ("TriggerMode",                "Off"),
         ("BinningHorizontal",          2),
         ("BinningVertical",            2),
         ("PixelFormat",                "RGB8"),