diff --git a/src/backend/model/fileaccess/MetadataCreationDate.ts b/src/backend/model/fileaccess/MetadataCreationDate.ts
index dc561a0e..f43b9442 100644
--- a/src/backend/model/fileaccess/MetadataCreationDate.ts
+++ b/src/backend/model/fileaccess/MetadataCreationDate.ts
@@ -1,10 +1,13 @@
 //The elements are [tag-name1, tag-name2, type of tag-name2]
-//tagname1 is typically a full date time, but in some cases tagname1 and tagname2 together make up a full timestamp
+//tagname1 is typically a full date time, but in some cases tagname1 and tagname2 together make up a full timestamp. The type makes it easier to code correct concatenation of tag1 and tag2
 
 //Interesting exiftool forums posts about some of these tags:
-//exif.DateTimeOriginal, exif.CreateDate/exif.DateTimeDigitized and exif.ModifyDate: https://exiftool.org/forum/index.php?topic=13170.msg71174#msg71174 
+//https://exiftool.org/forum/index.php?topic=13170.msg71174#msg71174 - about the meaning of exif.DateTimeOriginal, exif.CreateDate/exif.DateTimeDigitized and exif.ModifyDate
 //https://exiftool.org/forum/index.php?topic=15555.msg83536#msg83536
 
+//This is the PRIORITIZED LIST of tags which Pigallery2 uses to determine the date of creation of pictures.
+//The list is used for embedded picture metadata and xmp-sidecar files for both pictures and vidoes.
+
 export const DateTags: [string, string, string][] = [
   // Date tag                 Offset or time tag          Type  //Description
   ["exif.DateTimeOriginal",   "exif.OffsetTimeOriginal",  'O'], //Date and time when the original image was taken - shutter close time
diff --git a/src/backend/model/fileaccess/MetadataLoader.ts b/src/backend/model/fileaccess/MetadataLoader.ts
index 17f1659c..6e3f4811 100644
--- a/src/backend/model/fileaccess/MetadataLoader.ts
+++ b/src/backend/model/fileaccess/MetadataLoader.ts
@@ -249,6 +249,7 @@ export class MetadataLoader {
             if (fs.existsSync(sidecarPath)) {
               const sidecarData: any = await exifr.sidecar(sidecarPath, exifrOptions);
               if (sidecarData !== undefined) {
+                //note that since side cars are loaded last, data loaded here overwrites embedded metadata (in Pigallery2, not in the actual files)
                 MetadataLoader.mapMetadata(metadata, sidecarData);
                 break;
               }
@@ -363,6 +364,7 @@ export class MetadataLoader {
   }
 
   private static mapTimestampAndOffset(metadata: PhotoMetadata, exif: any) {
+    //This method looks for date tags matching the priorized list 'DateTags' of 'MetadataCreationDate'
     let ts: string, offset: string;
     for (let i = 0; i < DateTags.length; i++) {
       const [mainpath, extrapath, extratype] = DateTags[i];