Hi @caoxiaoran -
I don’t know what “deep.tif” is, but ArcGIS is telling you that this layer does not have a coordinate system assigned, and without a coordinate system it really doesn’t know where it is in the world. And NDR does require that all spatial layers have the same projected coordinate system.
If you have documentation on the source of deep.tif, hopefully it will tell you what the coordinate system is so you can assign it. In ArcGIS this is usually done through the layer’s Properties in ArcCatalog. You can also do a web search to learn more about working with coordinate systems.
~ Stacie
thank you ,i will try it ,if i have some questions,can i ask you ?
