diff --git a/sas/api.py b/sas/api.py
index 3cd03568..175e44c0 100644
--- a/sas/api.py
+++ b/sas/api.py
@@ -1,9 +1,10 @@
+from typing import Any, Literal
+
 from django.conf import settings
 from django.core.exceptions import ValidationError
 from django.db.models import F
 from django.urls import reverse
 from ninja import Body, File, Query
-from ninja.errors import HttpError
 from ninja_extra import ControllerBase, api_controller, paginate, route
 from ninja_extra.exceptions import NotFound, PermissionDenied
 from ninja_extra.pagination import PageNumberPaginationExtra
@@ -104,7 +105,11 @@ class PicturesController(ControllerBase):
     @route.post(
         "",
         permissions=[CanEdit],
-        response={200: None, 409: dict[str, list[str]]},
+        response={
+            200: None,
+            409: dict[Literal["detail"], dict[str, list[str]]],
+            422: dict[Literal["detail"], list[dict[str, Any]]],
+        },
         url_name="upload_picture",
     )
     def upload_picture(self, album_id: Body[int], picture: File[UploadedImage]):
@@ -127,7 +132,7 @@ class PicturesController(ControllerBase):
             new.full_clean()
             new.save()
         except ValidationError as e:
-            raise HttpError(status_code=409, message=str(e)) from e
+            return self.create_response({"detail": dict(e)}, status_code=409)
 
     @route.get(
         "/{picture_id}/identified",
diff --git a/sas/static/bundled/sas/album-index.ts b/sas/static/bundled/sas/album-index.ts
index b2a706d5..32f0f02f 100644
--- a/sas/static/bundled/sas/album-index.ts
+++ b/sas/static/bundled/sas/album-index.ts
@@ -5,6 +5,7 @@ import {
   type AlbumSchema,
   type PictureSchema,
   type PicturesFetchPicturesData,
+  type PicturesUploadPictureErrors,
   albumFetchAlbum,
   picturesFetchPictures,
   picturesUploadPicture,
@@ -93,6 +94,7 @@ document.addEventListener("alpine:init", () => {
     async sendPictures() {
       const input = this.$refs.pictures as HTMLInputElement;
       const files = input.files;
+      this.errors = [];
       this.progress.value = 0;
       this.progress.max = files.length;
       this.sending = true;
@@ -110,7 +112,15 @@ document.addEventListener("alpine:init", () => {
         body: { album_id: albumId, picture: file },
       });
       if (!res.response.ok) {
-        this.errors.push(`${file.name} : ${res.error.detail}`);
+        let msg = "";
+        if (res.response.status === 422) {
+          msg = (res.error as PicturesUploadPictureErrors[422]).detail
+            .map((err: Record<"ctx", Record<"error", string>>) => err.ctx.error)
+            .join(" ; ");
+        } else {
+          msg = Object.values(res.error.detail).join(" ; ");
+        }
+        this.errors.push(`${file.name} : ${msg}`);
       }
       this.progress.value += 1;
     },