diff --git a/src/main/java/org/micromanager/lightsheetmanager/api/AcquisitionSettingsScape.java b/src/main/java/org/micromanager/lightsheetmanager/api/AcquisitionSettingsScape.java
index fb0498f..aac2450 100644
--- a/src/main/java/org/micromanager/lightsheetmanager/api/AcquisitionSettingsScape.java
+++ b/src/main/java/org/micromanager/lightsheetmanager/api/AcquisitionSettingsScape.java
@@ -47,7 +47,7 @@ public interface AcquisitionSettingsScape extends AcquisitionSettings {
      *
      * @return immutable DefaultSliceSettings instance.
      */
-    DefaultSliceSettings slice();
+    SliceSettings slice();
 
     /**
      * Returns the immutable DefaultScanSettings instance.
diff --git a/src/main/java/org/micromanager/lightsheetmanager/api/internal/BaseAcquisitionSettings.java b/src/main/java/org/micromanager/lightsheetmanager/api/internal/BaseAcquisitionSettings.java
index 76b91f0..8d91871 100644
--- a/src/main/java/org/micromanager/lightsheetmanager/api/internal/BaseAcquisitionSettings.java
+++ b/src/main/java/org/micromanager/lightsheetmanager/api/internal/BaseAcquisitionSettings.java
@@ -5,6 +5,7 @@
 import com.google.gson.JsonDeserializer;
 import org.micromanager.lightsheetmanager.api.AcquisitionSettings;
 import org.micromanager.lightsheetmanager.api.ChannelSettings;
+import org.micromanager.lightsheetmanager.api.SliceSettings;
 import org.micromanager.lightsheetmanager.api.StageScanSettings;
 import org.micromanager.lightsheetmanager.model.DataStorage;
 
@@ -230,6 +231,11 @@ public static <T extends AcquisitionSettings> T fromJson(final String json, fina
                             // This forces Gson to use the concrete implementation class
                             return context.deserialize(jsonElement, DefaultChannelSettings.class);
                         })
+                .registerTypeAdapter(SliceSettings.class, (JsonDeserializer<SliceSettings>)
+                        (jsonElement, typeOfT, context) -> {
+                            // This forces Gson to use the concrete implementation class
+                            return context.deserialize(jsonElement, DefaultSliceSettings.class);
+                        })
                 .create();
         return gson.fromJson(json, cls);
     }
diff --git a/src/main/java/org/micromanager/lightsheetmanager/api/internal/DefaultSliceSettings.java b/src/main/java/org/micromanager/lightsheetmanager/api/internal/DefaultSliceSettings.java
index e3cf6ed..706f2b2 100644
--- a/src/main/java/org/micromanager/lightsheetmanager/api/internal/DefaultSliceSettings.java
+++ b/src/main/java/org/micromanager/lightsheetmanager/api/internal/DefaultSliceSettings.java
@@ -16,6 +16,11 @@ private DefaultSliceSettings(Builder builder) {
         periodMinimized_ = builder.periodMinimized_;
     }
 
+    // Note: used by GSON library for deserialization
+    private DefaultSliceSettings() {
+        this(new Builder());
+    }
+
     public static Builder builder() {
         return new Builder();
     }
diff --git a/src/main/java/org/micromanager/lightsheetmanager/api/internal/DefaultStageScanSettings.java b/src/main/java/org/micromanager/lightsheetmanager/api/internal/DefaultStageScanSettings.java
index e6a2719..a2b55ac 100644
--- a/src/main/java/org/micromanager/lightsheetmanager/api/internal/DefaultStageScanSettings.java
+++ b/src/main/java/org/micromanager/lightsheetmanager/api/internal/DefaultStageScanSettings.java
@@ -203,7 +203,7 @@ public Builder fromNegativeDirection(final boolean state) {
         }
 
         @Override
-        public StageScanSettings build() {
+        public DefaultStageScanSettings build() {
             return new DefaultStageScanSettings(this);
         }
 
diff --git a/src/main/java/org/micromanager/lightsheetmanager/api/internal/ScapeAcquisitionSettings.java b/src/main/java/org/micromanager/lightsheetmanager/api/internal/ScapeAcquisitionSettings.java
index e9e2095..2353ba7 100644
--- a/src/main/java/org/micromanager/lightsheetmanager/api/internal/ScapeAcquisitionSettings.java
+++ b/src/main/java/org/micromanager/lightsheetmanager/api/internal/ScapeAcquisitionSettings.java
@@ -2,6 +2,7 @@
 
 import org.micromanager.lightsheetmanager.api.AcquisitionSettingsScape;
 import org.micromanager.lightsheetmanager.api.ChannelSettings;
+import org.micromanager.lightsheetmanager.api.SliceSettings;
 import org.micromanager.lightsheetmanager.api.StageScanSettings;
 import org.micromanager.lightsheetmanager.api.data.AcquisitionMode;
 import org.micromanager.lightsheetmanager.api.data.CameraData;
@@ -18,7 +19,7 @@ public static class Builder extends BaseAcquisitionSettings.Builder<Builder> imp
         private ChannelSettings.Builder channelBuilder_ = DefaultChannelSettings.builder();
         private DefaultTimingSettings.Builder timingBuilder_ = DefaultTimingSettings.builder();
         private DefaultVolumeSettings.Builder volumeBuilder_ = DefaultVolumeSettings.builder();
-        private DefaultSliceSettings.Builder sliceBuilder_ = DefaultSliceSettings.builder();
+        private SliceSettings.Builder sliceBuilder_ = DefaultSliceSettings.builder();
         private StageScanSettings.Builder stageScanBuilder_ = DefaultStageScanSettings.builder();
         private DefaultSheetCalibration.Builder sheetCalibBuilder_ = DefaultSheetCalibration.builder();
         private DefaultSliceCalibration.Builder sliceCalibBuilder_ = DefaultSliceCalibration.builder();
@@ -191,7 +192,7 @@ public DefaultVolumeSettings.Builder volumeBuilder() {
             return volumeBuilder_;
         }
 
-        public DefaultSliceSettings.Builder sliceBuilder() {
+        public SliceSettings.Builder sliceBuilder() {
             return sliceBuilder_;
         }
 
@@ -236,7 +237,7 @@ public String toString() {
     private final ChannelSettings channels_;
     private final DefaultTimingSettings timing_;
     private final DefaultVolumeSettings volume_;
-    private final DefaultSliceSettings slice_;
+    private final SliceSettings slice_;
     private final StageScanSettings stageScan_;
     private final DefaultSheetCalibration sheetCalibration_;
     private final DefaultSliceCalibration sliceCalibration_;
@@ -260,7 +261,7 @@ private ScapeAcquisitionSettings(Builder builder) {
         channels_ = builder.channelBuilder().build();
         timing_ = builder.timingBuilder_.build();
         volume_ = builder.volumeBuilder_.build();
-        slice_ = builder.sliceBuilder_.build();
+        slice_ = builder.sliceBuilder().build();
         stageScan_ = builder.stageScanBuilder().build();
         sheetCalibration_ = builder.sheetCalibBuilder_.build();
         sliceCalibration_ = builder.sliceCalibBuilder_.build();
@@ -322,7 +323,7 @@ public DefaultVolumeSettings volume() {
      * @return immutable DefaultSliceSettings instance.
      */
     @Override
-    public DefaultSliceSettings slice() {
+    public SliceSettings slice() {
         return slice_;
     }
 
diff --git a/src/main/java/org/micromanager/lightsheetmanager/gui/tabs/acquisition/SlicePanel.java b/src/main/java/org/micromanager/lightsheetmanager/gui/tabs/acquisition/SlicePanel.java
index c453ac4..7516719 100644
--- a/src/main/java/org/micromanager/lightsheetmanager/gui/tabs/acquisition/SlicePanel.java
+++ b/src/main/java/org/micromanager/lightsheetmanager/gui/tabs/acquisition/SlicePanel.java
@@ -1,7 +1,7 @@
 package org.micromanager.lightsheetmanager.gui.tabs.acquisition;
 
+import org.micromanager.lightsheetmanager.api.SliceSettings;
 import org.micromanager.lightsheetmanager.api.data.CameraMode;
-import org.micromanager.lightsheetmanager.api.internal.DefaultSliceSettings;
 import org.micromanager.lightsheetmanager.gui.components.CheckBox;
 import org.micromanager.lightsheetmanager.gui.components.Label;
 import org.micromanager.lightsheetmanager.gui.components.Panel;
@@ -45,7 +45,7 @@ private void createUserInterface() {
                 "[]5[]"
         );
 
-        final DefaultSliceSettings sliceSettings = model_.acquisitions().settings().slice();
+        final SliceSettings sliceSettings = model_.acquisitions().settings().slice();
         final boolean isSlicePeriodMinimized = sliceSettings.periodMinimized();
 
         // regular panel