diff --git a/src/Controller/DeviceApiController.php b/src/Controller/DeviceApiController.php
index d15cb51..4cfb9b0 100644
--- a/src/Controller/DeviceApiController.php
+++ b/src/Controller/DeviceApiController.php
@@ -215,8 +215,9 @@ class DeviceApiController extends AbstractController
             $this->renderBinToPng(
                 $binPath,
                 $pngPath,
-                $device->getModel()->width($device->getOrientation()),
-                $device->getModel()->height($device->getOrientation()),
+                $device->getModel()->nativeWidth(),
+                $device->getModel()->nativeHeight(),
+                $device->getOrientation(),
             );
         }
 
@@ -229,7 +230,7 @@ class DeviceApiController extends AbstractController
         return $response;
     }
 
-    private function renderBinToPng(string $binPath, string $pngPath, int $width, int $height): void
+    private function renderBinToPng(string $binPath, string $pngPath, int $width, int $height, Orientation $orientation): void
     {
         $bin   = (string) file_get_contents($binPath);
         $len   = strlen($bin);
@@ -250,6 +251,14 @@ class DeviceApiController extends AbstractController
 
         $im = new \Imagick();
         $im->readImageBlob($ppm);
+
+        // The .bin is always laid out in EPD-native scan order. For portrait,
+        // the renderer pre-rotated the photo 90° CW; rotate -90° here so the
+        // browser-side preview shows the photo upright.
+        if ($orientation === Orientation::Portrait) {
+            $im->rotateImage(new \ImagickPixel('white'), -90);
+        }
+
         $im->setImageFormat('png');
         $im->writeImage($pngPath);
         $im->destroy();
diff --git a/src/Enum/DeviceModel.php b/src/Enum/DeviceModel.php
index 9e4452f..194cc3b 100644
--- a/src/Enum/DeviceModel.php
+++ b/src/Enum/DeviceModel.php
@@ -17,4 +17,16 @@ enum DeviceModel: string
     {
         return $orientation === Orientation::Portrait ? 800 : 480;
     }
+
+    /** EPD's hardware scan-row width — independent of user orientation. */
+    public function nativeWidth(): int
+    {
+        return 800;
+    }
+
+    /** EPD's hardware scan-row count — independent of user orientation. */
+    public function nativeHeight(): int
+    {
+        return 480;
+    }
 }
diff --git a/src/MessageHandler/RenderImageMessageHandler.php b/src/MessageHandler/RenderImageMessageHandler.php
index d297403..670947b 100644
--- a/src/MessageHandler/RenderImageMessageHandler.php
+++ b/src/MessageHandler/RenderImageMessageHandler.php
@@ -70,7 +70,7 @@ final class RenderImageMessageHandler
                 : $this->projectDir . '/' . $image->getStoragePath();
             $width        = $model->width($orientation);
             $height       = $model->height($orientation);
-            $bin          = $this->renderToBin($originalPath, $width, $height);
+            $bin          = $this->renderToBin($originalPath, $width, $height, $orientation);
 
             $relPath = 'var/storage/images/' . $image->getId()
                 . '/' . $model->value . '_' . $orientation->value . '.bin';
@@ -87,7 +87,7 @@ final class RenderImageMessageHandler
         $this->em->flush();
     }
 
-    private function renderToBin(string $path, int $width, int $height): string
+    private function renderToBin(string $path, int $width, int $height, Orientation $orientation): string
     {
         $imagick = new \Imagick($path);
         $imagick->setImageAlphaChannel(\Imagick::ALPHACHANNEL_REMOVE);
@@ -95,6 +95,16 @@ final class RenderImageMessageHandler
         $imagick->mergeImageLayers(\Imagick::LAYERMETHOD_FLATTEN);
         $imagick->autoOrient();
         $imagick->cropThumbnailImage($width, $height);
+
+        // Portrait: rotate the cropped photo 90° CW so the packed .bin's row
+        // layout matches the EPD's native 800-pixel scan order. The frame is
+        // physically rotated 90° CCW for portrait (ribbon on left), so the
+        // photo's bottom edge maps to the EPD's left column. Firmware streams
+        // bytes raw — no orientation awareness on-device.
+        if ($orientation === Orientation::Portrait) {
+            $imagick->rotateImage(new \ImagickPixel('white'), 90);
+        }
+
         $imagick->setImageColorspace(\Imagick::COLORSPACE_SRGB);
 
         // Auto-levels: stretch the tonal range, clipping 1% at each end.