diff --git a/trellis/pipelines/trellis_image_to_3d.py b/trellis/pipelines/trellis_image_to_3d.py
index f781e348..64ea6f1f 100644
--- a/trellis/pipelines/trellis_image_to_3d.py
+++ b/trellis/pipelines/trellis_image_to_3d.py
@@ -105,7 +105,8 @@ def preprocess_image(self, input: Image.Image) -> Image.Image:
             output = rembg.remove(input, session=self.rembg_session)
         output_np = np.array(output)
         alpha = output_np[:, :, 3]
-        bbox = np.argwhere(alpha > 0.8 * 255)
+        alpha_cutoff = 0.8
+        bbox = np.argwhere(alpha > alpha_cutoff * 255)
         bbox = np.min(bbox[:, 1]), np.min(bbox[:, 0]), np.max(bbox[:, 1]), np.max(bbox[:, 0])
         center = (bbox[0] + bbox[2]) / 2, (bbox[1] + bbox[3]) / 2
         size = max(bbox[2] - bbox[0], bbox[3] - bbox[1])
@@ -114,7 +115,7 @@ def preprocess_image(self, input: Image.Image) -> Image.Image:
         output = output.crop(bbox)  # type: ignore
         output = output.resize((518, 518), Image.Resampling.LANCZOS)
         output = np.array(output).astype(np.float32) / 255
-        output = output[:, :, :3] * output[:, :, 3:4]
+        output = output[:, :, :3] * (output[:, :, 3:4] > alpha_cutoff)
         output = Image.fromarray((output * 255).astype(np.uint8))
         return output