diff --git a/src/app/TileBasemap.cpp b/src/app/TileBasemap.cpp
index caa337c..8a12977 100644
--- a/src/app/TileBasemap.cpp
+++ b/src/app/TileBasemap.cpp
@@ -292,6 +292,7 @@ vtkSmartPointer<vtkActor> TileBasemap::buildFlat(int z, int x, int y,
     actor->SetMapper(mapper);
     actor->SetTexture(tex);
     actor->GetProperty()->LightingOff();  // 底图不受场景光照
+    actor->SetUseBounds(false);  // 底图不参与包围盒/相机取景：否则坐标轴/适配被~公里级底图撑大
     return actor;
 }
 
@@ -417,6 +418,7 @@ vtkSmartPointer<vtkActor> TileBasemap::buildWarped(int sz, int sx, int sy, int d
     actor->SetMapper(mapper);
     actor->SetTexture(tex);
     actor->GetProperty()->LightingOff();
+    actor->SetUseBounds(false);  // 同 buildFlat：底图不参与包围盒/相机取景
     return actor;
 }