I use binocs, a scope and my camera (which I can then use to zoom in and have a closer look!). I have gotten it wrong on many occasions - sent a picture to Tracy of Princess, and she comes back with "nice shot of Trey!". Princess is bigger, for sure, and has a lot of 'flecks' higher on her breast. Ivy has a pretty white 'clean' breast, and I think is darker all over.