I have a Canon 500D with kit lenses. I live in the bush in Central Victoria surrounded by woodland birds, which I attempt to photograph with the 55-250mm kit lens. Time has come to get something better.

I am contemplating either a Sigma 150-500mm zoom or a Canon 400 f5.6L. The birds around here are quite small and the 500mm idea appeals as does image stabilising. But I imagine that the quality of the 400 L would be much better. I am also thinking that a 1.4 converter will give me the length if I need it but with some loss of quality.

I would be grateful for any thoughts or feedback that people might have about this choice. At present I am leaning towards the 400 L.

Many thanks for your thoughts