diff --git a/lib/Db/TimelineWrite.php b/lib/Db/TimelineWrite.php
index 323964e5..27d14679 100644
--- a/lib/Db/TimelineWrite.php
+++ b/lib/Db/TimelineWrite.php
@@ -129,20 +129,21 @@ class TimelineWrite
         }
 
         // Clean up EXIF to keep only useful metadata
-        foreach ($exif as $key => &$value) {
+        $filteredExif = [];
+        foreach ($exif as $key => $value) {
             // Truncate any fields > 2048 chars
             if (\is_string($value) && \strlen($value) > 2048) {
-                $exif[$key] = substr($value, 0, 2048);
+                $value = substr($value, 0, 2048);
             }
 
-            // These are huge and not needed
-            if (!EXIF_FIELDS_LIST[$key] ?? false) {
-                unset($exif[$key]);
+            // Only keep fields in the whitelist
+            if (\array_key_exists($key, EXIF_FIELDS_LIST)) {
+                $filteredExif[$key] = $value;
             }
         }
 
         // Store JSON string
-        $exifJson = json_encode($exif);
+        $exifJson = json_encode($filteredExif);
 
         // Store error if data > 64kb
         if (\is_string($exifJson)) {