Many birders like to take photographs of birds. This is difficult to do well unless one has good, expensive cameras and long lenses. Telescopes can be attached to cameras. This is called digiscoping. Modern phone cameras are very useful, and can produce good results. They are easier to use in many situations. But those who do use telescopes may need a "hide", usually a canvas tent. A hide means the birds cannot see you, and it keeps you warmer than being out in the open. Water birds are usually photographed from hides.