Update README.md

README.md

@@ -17,6 +17,8 @@ For up-to-date model card information, please see the [original repo](https://gi
 
 ### How to use
 
+**Warning: The feature extractor in this repo is a copy of the one from [`microsoft/resnet-50`](https://huggingface.co/microsoft/resnet-50). We never verified if this image prerprocessing is the one used with DINO ResNet-50.**
+
 ```python
 from transformers import AutoFeatureExtractor, ResNetModel
 from PIL import Image