How to get TGraphicField into a TPicture??


Can you tell me the proper way to get the contents of a TGraphicField's
bitmap into a TPicture bitmap?

TGraphicField.Assign works to >load< the TGraphicField, but .AssignTo is
protected.  The .Assign for TPicture and TBitmap don't appear to know
anything about TGraphicField.

I've tried the following code that uses TStreams, but it just access
  TM := TMemoryStream.Create;
  GraphicField.SaveToStream(TM);  //Croaks here

I'd appreciate any suggestions anyone can offer. Thanks