diff --git a/backend/src/main/java/org/raddatz/familienarchiv/service/FileService.java b/backend/src/main/java/org/raddatz/familienarchiv/service/FileService.java
index acf6f23d..29ca2be6 100644
--- a/backend/src/main/java/org/raddatz/familienarchiv/service/FileService.java
+++ b/backend/src/main/java/org/raddatz/familienarchiv/service/FileService.java
@@ -114,7 +114,8 @@ public class FileService {
 
     /**
      * Generates a presigned URL for downloading an object from S3/MinIO.
-     * Valid for 15 minutes — enough for OCR processing on CPU.
+     * Valid for 1 hour — covers multi-page documents on CPU-only OCR hardware
+     * (a 100-page document at 10 s/page takes ~17 min; 1 h gives ample headroom).
      */
     public String generatePresignedUrl(String s3Key) {
         GetObjectRequest getObjectRequest = GetObjectRequest.builder()
@@ -123,7 +124,7 @@ public class FileService {
                 .build();
 
         GetObjectPresignRequest presignRequest = GetObjectPresignRequest.builder()
-                .signatureDuration(Duration.ofMinutes(15))
+                .signatureDuration(Duration.ofHours(1))
                 .getObjectRequest(getObjectRequest)
                 .build();