I was very excited to open this lens when I got it in the mail. I bought it specifically for comet PanSTARRS and ISON (which will be arriving later in the year) as well as to extend the possibilities of range since I like to go hiking far away from city lights to take images of the environment, wildlife, and of course, stars. This lens was amazing at capturing comet PanSTARRS, although not as close since it only reaches to 300mm, but still takes wonderful clean shots. The lens can zoom to the Pleiades star cluster where it fills the entire screen. Nice shots too, but only limited to the 4.5 aperture minimum. I have also used this lens to capture some real nice movement of my dog (she goes with me on adventures). When shooting still objects from afar with this lens, use a tripod! Since the lens is around 8in long in total, it may slightly shake around if you dont have a stable tripod to prevent that. Example is when I took images of PanSTARRS. I had to make sure I didnt bump the camera so I can get a clear shot since the comet was a single point in the sky that I was focusing on. All other things should be fine. A shutter remote can also help with that, or use the timer! And to take into consideration of wind that can rock the camera ever so slightly but can cause motion blur in the image.