为什么在调用img ng-src时没有调用我的http错误响应？

I have the following problem: I am trying to trap an HTTP 500 response from the server but the intercept is not getting the 500 response. This is generated by an img src call to an unauthorized URL (technically the server should be returning a 4xx, but it returns a 5xx --> its a 3rd party server. I have the following problem: I am trying to tr