Canon 550 camera lens with
Fixed focus lens: is only a fixed focal length of the lens, only a focal length, no zoom function. The design of the fixed focus lens is much simpler than the zoom lens, but the general zoom lens will have an effect on the imaging during zooming, and the biggest advantage of the focus lens relative to the zooming machine is that the focus is fast and the image quality is stable. Many have a fixed focus lens digital camera shooting images of moving objects clear and stable, focusing is very accurate, the screen is fine, grainy is very slight, metering is also more accurate.
Need to be based on personal circumstances and economic capacity to set, in general, with a standard fixed focus lens (such as 50mm 1.8) plus a zoom head (such as 18-135mm or 18-55mm) can meet the daily needs. Travel zoom is much easier to use than focus.
Zoom lens: in a certain range can change the focal length, resulting in different width of the field of view, different sizes of images and different scene range of the camera lens. Zoom lens does not change the shooting distance, you can change the focal length to change the shooting range, it is very conducive to the composition of the screen. As a zoom lens can take on the role of a number of fixed focus lens, travel not only reduce the number of carrying photographic equipment, but also save the time to replace the lens.
