diff --git a/src/main/java/org/micromanager/lightsheetmanager/model/acquisitions/AcquisitionEngine.java b/src/main/java/org/micromanager/lightsheetmanager/model/acquisitions/AcquisitionEngine.java
index 7e9aea5e..f7921867 100644
--- a/src/main/java/org/micromanager/lightsheetmanager/model/acquisitions/AcquisitionEngine.java
+++ b/src/main/java/org/micromanager/lightsheetmanager/model/acquisitions/AcquisitionEngine.java
@@ -18,6 +18,7 @@
 import org.micromanager.data.internal.PropertyKey;
 import org.micromanager.lightsheetmanager.LightSheetManager;
 import org.micromanager.lightsheetmanager.api.AcquisitionManager;
+import org.micromanager.lightsheetmanager.api.AcquisitionSettings;
 import org.micromanager.lightsheetmanager.api.TimingSettings;
 import org.micromanager.lightsheetmanager.api.data.AcquisitionMode;
 import org.micromanager.lightsheetmanager.api.internal.ScapeAcquisitionSettings;
@@ -479,6 +480,20 @@ public void requestResume() {
         }
     }
 
+    /**
+     * Returns the number of time points a run acquires.
+     *
+     * <p>The time point count keeps its value while time points are off, so that turning them
+     * back on restores it. Anything that sizes or checks a run reads the count through here,
+     * which gives 1 in that case.
+     *
+     * @param settings the acquisition settings
+     * @return the time point count, or 1 when time points are off
+     */
+    static int numTimePointsToAcquire(final AcquisitionSettings settings) {
+        return settings.isUsingTimePoints() ? settings.numTimePoints() : 1;
+    }
+
     /**
      * Higher level stuff in MM may depend on many hidden, poorly documented
      * ways on summary metadata generated by the acquisition engine.
@@ -487,7 +502,7 @@ public void requestResume() {
     protected DefaultSummaryMetadata addMMSummaryMetadata(JSONObject summaryMetadata) {
         return addMMSummaryMetadata(summaryMetadata, acqSettings_,
                 studio_.positions().getPositionList(),
-                acqSettings_.isUsingTimePoints() ? acqSettings_.numTimePoints() : 1);
+                numTimePointsToAcquire(acqSettings_));
     }
 
     /**
diff --git a/src/main/java/org/micromanager/lightsheetmanager/model/acquisitions/AcquisitionEngineScape.java b/src/main/java/org/micromanager/lightsheetmanager/model/acquisitions/AcquisitionEngineScape.java
index 5675f633..78bb88a2 100644
--- a/src/main/java/org/micromanager/lightsheetmanager/model/acquisitions/AcquisitionEngineScape.java
+++ b/src/main/java/org/micromanager/lightsheetmanager/model/acquisitions/AcquisitionEngineScape.java
@@ -503,7 +503,7 @@ private boolean startTimePointAcquisition(final ScapeAcquisitionSettings setting
         final boolean separate = datasetTimeIndex >= 0;
         // one time point per dataset in separate mode, the whole series otherwise
         final int numTimePoints = separate ? 1
-                : (settings.isUsingTimePoints() ? settings.numTimePoints() : 1);
+                : numTimePointsToAcquire(settings);
 
         //////////////////////////////////////
         // Begin AcqEngJ integration
@@ -1547,7 +1547,7 @@ private boolean doHardwareCalculations(PLogicScape plc) {
         //  the port.
         if (acqSettings_.isUsingMultiplePositions()) {
             if (isUsingHardwareTimePoints
-                    || (acqSettings_.numTimePoints() > 1
+                    || (numTimePointsToAcquire(acqSettings_) > 1
                         && timepointIntervalMs < timepointDuration * 1.2)) {
                 // warn the user but allow the acquisition to continue
                 asb_.useHardwareTimePoints(false);
@@ -1613,7 +1613,7 @@ private boolean doHardwareCalculations(PLogicScape plc) {
             }
         }
 
-        final int numTimePoints = acqSettings_.isUsingTimePoints() ? acqSettings_.numTimePoints() : 1;
+        final int numTimePoints = numTimePointsToAcquire(acqSettings_);
         if (!acqSettings_.isUsingMultiplePositions() && numTimePoints > 1) {
             if (timepointIntervalMs < volumeDuration) {
                 studio_.logs().showError("Time point interval shorter than the time to collect a single volume.");
@@ -2072,7 +2072,7 @@ private void updateTotalTimeDurationLabel(final JLabel label) {
     }
 
     private double computeTotalTimeDuration() {
-        final int numTimePoints = acqSettings_.isUsingTimePoints() ? acqSettings_.numTimePoints() : 1;
+        final int numTimePoints = numTimePointsToAcquire(acqSettings_);
         return (numTimePoints - 1) * acqSettings_.timePointIntervalSec() + computeTimePointDuration() / 1000.0;
     }