diff --git a/src/ophyd_async/fastcs/eiger/_trigger_logic.py b/src/ophyd_async/fastcs/eiger/_trigger_logic.py
index e4f7a14c57..86f0dce70b 100644
--- a/src/ophyd_async/fastcs/eiger/_trigger_logic.py
+++ b/src/ophyd_async/fastcs/eiger/_trigger_logic.py
@@ -14,7 +14,8 @@ async def _prepare_detector(
 ):
     coros = [
         detector.trigger_mode.set(trigger_mode),
-        detector.nimages.set(num),
+        detector.ntrigger.set(num),
+        detector.nimages.set(1),
     ]
     if livetime:
         coros += [
diff --git a/tests/unit_tests/fastcs/eiger/test_eiger_detector.py b/tests/unit_tests/fastcs/eiger/test_eiger_detector.py
index 2570f72f28..ec06e51c76 100644
--- a/tests/unit_tests/fastcs/eiger/test_eiger_detector.py
+++ b/tests/unit_tests/fastcs/eiger/test_eiger_detector.py
@@ -40,7 +40,8 @@ async def test_prepare_internal_calls_correct_parameters(
         detector,
         [
             call.detector.trigger_mode.put(EigerTriggerMode.INTERNAL),
-            call.detector.nimages.put(10),
+            call.detector.ntrigger.put(10),
+            call.detector.nimages.put(1),
             call.detector.count_time.put(0.1),
             call.detector.frame_time.put(0.1),
             call.od.acquisition_id.put(""),