diff --git a/src/main/java/org/orph2020/pst/common/json/OpticalTelescopeDataId.java b/src/main/java/org/orph2020/pst/common/json/OpticalTelescopeDataId.java
new file mode 100644
index 0000000..ba2b0ca
--- /dev/null
+++ b/src/main/java/org/orph2020/pst/common/json/OpticalTelescopeDataId.java
@@ -0,0 +1,51 @@
+package org.orph2020.pst.common.json;
+
+import jakarta.persistence.Embeddable;
+import java.io.Serializable;
+import java.util.Objects;
+
+
+@Embeddable
+public class OpticalTelescopeDataId implements Serializable {
+
+    private String proposalID;
+    private String observationID;
+
+    public OpticalTelescopeDataId() {
+    }
+
+    public OpticalTelescopeDataId(String proposalID, String observationID) {
+        this.proposalID = proposalID;
+        this.observationID = observationID;
+    }
+
+    public String getProposalID() {
+        return proposalID;
+    }
+
+    public void setProposalID(String proposalID) {
+        this.proposalID = proposalID;
+    }
+
+    public String getObservationID() {
+        return observationID;
+    }
+
+    public void setObservationID(String observationID) {
+        this.observationID = observationID;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        OpticalTelescopeDataId that = (OpticalTelescopeDataId) o;
+        return Objects.equals(proposalID, that.proposalID) &&
+               Objects.equals(observationID, that.observationID);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(proposalID, observationID);
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/org/orph2020/pst/common/json/OpticalTelescopeDataLoad.java b/src/main/java/org/orph2020/pst/common/json/OpticalTelescopeDataLoad.java
index 546de14..15cf279 100644
--- a/src/main/java/org/orph2020/pst/common/json/OpticalTelescopeDataLoad.java
+++ b/src/main/java/org/orph2020/pst/common/json/OpticalTelescopeDataLoad.java
@@ -3,10 +3,10 @@
 // data type for the loading of the optional telescope data.
 public class OpticalTelescopeDataLoad {
     // the proposal id.
-    public String proposalID;
+    private String proposalID;
 
     // the observation id for the telescope data.
-    public String observationID;
+    private String observationID;
 
     /**
      * the constructor for the data saved within the database for a given
@@ -18,4 +18,29 @@ public OpticalTelescopeDataLoad(String proposalID, String observationID) {
         this.proposalID = proposalID;
         this.observationID = observationID;
     }
+
+    /**
+     * the default constructor for the data saved within the database for a given
+     * observation.
+     */
+    public OpticalTelescopeDataLoad() {
+        this.proposalID = null;
+        this.observationID = null;
+    }
+
+    public String getProposalID() {
+        return proposalID;
+    }
+
+    public void setProposalID(String proposalID) {
+        this.proposalID = proposalID;
+    }
+
+    public String getObservationID() {
+        return observationID;
+    }
+
+    public void setObservationID(String observationID) {
+        this.observationID = observationID;
+    }
 }
diff --git a/src/main/java/org/orph2020/pst/common/json/OpticalTelescopeDataSave.java b/src/main/java/org/orph2020/pst/common/json/OpticalTelescopeDataSave.java
index 4d1563d..0c82288 100644
--- a/src/main/java/org/orph2020/pst/common/json/OpticalTelescopeDataSave.java
+++ b/src/main/java/org/orph2020/pst/common/json/OpticalTelescopeDataSave.java
@@ -1,13 +1,32 @@
 package org.orph2020.pst.common.json;
-
+import jakarta.persistence.*;
 import java.util.HashMap;
+import java.util.Map;
+
+@Entity
+@Table(name = "optical_telescope_data")
+public class OpticalTelescopeDataSave {
+    @EmbeddedId
+    private OpticalTelescopeDataId primaryKey;
+
+    @ElementCollection
+    @CollectionTable(name = "telescope_choices", joinColumns = {
+        @JoinColumn(name = "proposal_id", referencedColumnName = "proposalID"),
+        @JoinColumn(name = "observation_id", referencedColumnName = "observationID")
+    })
 
-public class OpticalTelescopeDataSave extends OpticalTelescopeDataLoad{
     // the new states of the choices.
-    HashMap<String, String> choices;
+    @MapKeyColumn(name = "choice_key")
+    @Column(name = "choice_value")
+    private Map<String, String> choices;
 
     // the telescope name.
-    public String telescopeName;
+    @Column(name = "telescope_name")
+    private String telescopeName;
+
+    // the instrument name.
+    @Column(name = "instrument_name")
+    private String instrumentName;
 
     /**
      * constructor for the telescope data for saving.
@@ -15,13 +34,51 @@ public class OpticalTelescopeDataSave extends OpticalTelescopeDataLoad{
      * @param proposalID: the proposal id.
      * @param observationID: the observation id.
      * @param telescopeName: the telescope name.
+     * @param instrumentName: the instrument name chosen for the choices.
      * @param choices: the choices made.
      */
     public OpticalTelescopeDataSave(
             String proposalID, String observationID, String telescopeName,
-            HashMap<String, String> choices) {
-        super(proposalID, observationID);
+            String instrumentName, HashMap<String, String> choices) {
+        this.primaryKey = new OpticalTelescopeDataId(proposalID, observationID);
         this.telescopeName = telescopeName;
+        this.instrumentName = instrumentName;
+        this.choices = choices;
+    }
+
+    public OpticalTelescopeDataSave() {
+        // No-argument constructor for Hibernate ORM
+    }
+
+    public Map<String, String> getChoices() {
+        return choices;
+    }
+
+    public void setChoices(Map<String, String> choices) {
         this.choices = choices;
     }
+
+    public void setTelescopeName(String telescopeName) {
+        this.telescopeName = telescopeName;
+    }
+
+    public void setInstrumentName(String instrumentName) {
+        this.instrumentName = instrumentName;
+    }
+
+    public String getTelescopeName() {
+        return telescopeName;
+    }
+
+    public String getInstrumentName() {
+        return instrumentName;
+    }
+
+    public OpticalTelescopeDataId getPrimaryKey() {
+        return primaryKey;
+    }
+
+    public void setPrimaryKey(OpticalTelescopeDataId primaryKey) {
+        this.primaryKey = primaryKey;
+    }
 }