Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Excelent for film/digital SLR

I purchased my copy in July 2008, and I have been very satisfied with it ever since. This is a very good and fast lens, and while modern digital cameras have an adjustable ISO, for film it's a blessing with its wide aperture at f2.8. I can take photos at night with ISO 400 film! Sure, the lens isn't problem-free: it's kind of noisy (most of my lenses are Nikon AF-S... very quiet), and at times it seems to focus-hunt with my F5. It is also very heavy, the zoom ring turns in what to me is the opposite direction, and the filter size is quite unusual (82mm). However, in my experience, it's very resistant to flare and quite well-built. I wouldn't hesitate to put this lense together with others for professional photographers, because it does perform well. Besides, I find that it causes very little noticeable distortion at its wide end. In short, a necessary lens for those demanding photographers who want a walk-about versatile zoom.