diff --git a/backend/__tests__/services/photoProcessor.processPhoto.test.js b/backend/__tests__/services/photoProcessor.processPhoto.test.js
index 763b213e..d5935300 100644
--- a/backend/__tests__/services/photoProcessor.processPhoto.test.js
+++ b/backend/__tests__/services/photoProcessor.processPhoto.test.js
@@ -75,6 +75,13 @@ jest.mock('../../src/services/imageProcessor', () => {
     withLocalCopy: jest.fn(async (key, fn) =>
       fn(`/tmp/local-copy-${require('path').basename(key)}`)
     ),
+    // Pass-through for ordinary (non-RAW) images: returns the path unchanged
+    // with a no-op cleanup, matching the real helper's behaviour for jpg/png.
+    withProcessableImage: jest.fn(async (localPath) => ({
+      path: localPath,
+      outputBasename: undefined,
+      cleanup: () => {},
+    })),
   };
 });
 
diff --git a/backend/src/services/photoProcessor.js b/backend/src/services/photoProcessor.js
index eec86982..986df36a 100644
--- a/backend/src/services/photoProcessor.js
+++ b/backend/src/services/photoProcessor.js
@@ -465,21 +465,31 @@ async function processPhoto(photoId) {
         if (result.metadata.height) updateData.height = result.metadata.height;
       }
     } else {
+      // RAW/DNG can't be sharp-decoded directly — extract the embedded JPEG
+      // preview and thumbnail/measure that. Pass-through for ordinary images.
+      // This is the ASYNC worker path (backgroundProcessor → processPhoto), the
+      // one real uploads actually take; the synchronous processUploadedPhotos()
+      // has the same handling.
+      const proc = await withProcessableImage(localPath, photo.filename);
       try {
-        const thumbnailPath = await generateThumbnail(localPath);
-        if (thumbnailPath) updateData.thumbnail_path = thumbnailPath;
-      } catch (e) {
-        logger.warn(`processPhoto: thumbnail generation failed for ${photoId}`, { error: e.message });
-      }
-      try {
-        const sharp = require('sharp');
-        const metadata = await sharp(localPath).metadata();
-        if (metadata.width && metadata.height) {
-          updateData.width = metadata.width;
-          updateData.height = metadata.height;
+        try {
+          const thumbnailPath = await generateThumbnail(proc.path, { outputBasename: proc.outputBasename });
+          if (thumbnailPath) updateData.thumbnail_path = thumbnailPath;
+        } catch (e) {
+          logger.warn(`processPhoto: thumbnail generation failed for ${photoId}`, { error: e.message });
         }
-      } catch (e) {
-        logger.warn(`processPhoto: dimensions extraction failed for ${photoId}`, { error: e.message });
+        try {
+          const sharp = require('sharp');
+          const metadata = await sharp(proc.path).metadata();
+          if (metadata.width && metadata.height) {
+            updateData.width = metadata.width;
+            updateData.height = metadata.height;
+          }
+        } catch (e) {
+          logger.warn(`processPhoto: dimensions extraction failed for ${photoId}`, { error: e.message });
+        }
+      } finally {
+        await proc.cleanup();
       }
     }
   });
diff --git a/backend/src/services/photoReplacementService.js b/backend/src/services/photoReplacementService.js
index 3680cbbd..8799825c 100644
--- a/backend/src/services/photoReplacementService.js
+++ b/backend/src/services/photoReplacementService.js
@@ -10,7 +10,7 @@ const path = require('path');
 const fsp = require('fs/promises');
 const sharp = require('sharp');
 const { db } = require('../database/db');
-const { generateThumbnail, extractCaptureDate } = require('./imageProcessor');
+const { generateThumbnail, extractCaptureDate, withProcessableImage } = require('./imageProcessor');
 const { generatePhotoFilename } = require('../utils/filenameSanitizer');
 const watermarkGeneratorService = require('./watermarkGeneratorService');
 const { getStorage } = require('./storage');
@@ -61,24 +61,30 @@ async function replacePhoto(existingPhoto, newFileTempPath, { originalFilename,
       // No EXIF — keep null
     }
 
-    let width = null;
-    let height = null;
-    try {
-      const metadata = await sharp(newFileTempPath).metadata();
-      width = metadata.width || null;
-      height = metadata.height || null;
-    } catch {
-      // Non-image or corrupt
-    }
-
     const stats = await fsp.stat(newFileTempPath);
 
-    // Generate new thumbnail FROM the local temp before uploading the original.
+    // RAW/DNG isn't sharp-decodable — extract the embedded JPEG preview first
+    // (pass-through for ordinary images), then measure + thumbnail that. Mirrors
+    // the ingest paths (processPhoto / processUploadedPhotos).
+    let width = null;
+    let height = null;
     let thumbnailPath = null;
+    const proc = await withProcessableImage(newFileTempPath, originalFilename);
     try {
-      thumbnailPath = await generateThumbnail(newFileTempPath);
-    } catch {
-      logger.warn('Failed to generate thumbnail for replaced photo', { photoId: existingPhoto.id });
+      try {
+        const metadata = await sharp(proc.path).metadata();
+        width = metadata.width || null;
+        height = metadata.height || null;
+      } catch {
+        // Non-image or corrupt
+      }
+      try {
+        thumbnailPath = await generateThumbnail(proc.path, { outputBasename: proc.outputBasename });
+      } catch {
+        logger.warn('Failed to generate thumbnail for replaced photo', { photoId: existingPhoto.id });
+      }
+    } finally {
+      await proc.cleanup();
     }
 
     // Delete old assets BEFORE uploading the new key — if they share the path