Thanks Oren & btaylor, the lens does have fantastic sharpness. I don't think my shots have great light and interesting backgrounds like Nate....mostly because they are shot in my backyard which is surrounded by tall trees that filter out the morning and evening sun and also cause a diffuse green background in summer or diffuse grey in winter. But I like trying to get detailed portrait type shots of the birds from close range. The biggest challenge is to get a fast enough shutter speed to get a really sharp image.