change splatfacto-big densify_grad_thresh to 0.0005

nerfstudio/configs/method_configs.py

@@ -663,7 +663,7 @@
         ),
         model=SplatfactoModelConfig(
             cull_alpha_thresh=0.005,
-            densify_grad_thresh=0.0006,
+            densify_grad_thresh=0.0005,
         ),
     ),
     optimizers={