Sigma Lenses for Pentax Cameras
Any camera is only as good as its lens, which is one reason why so many photographers spend so much time and money collecting lenses for their favourite cameras. While most companies offer both cameras and lenses, companies like Sigma make camera lenses for a wide range of bodies including Pentax.Focus
The primary job of camera lenses is to focus light on the sensor. In the old days that meant film, but even though it's now a digital sensor, the principle remains the same. The biggest advance in focus is autofocus, but not everyone wants to use that feature; particularly photographers who want to draw attention to one particular area of the picture. Using a Sigma auto and manual focus lens for Pentax cameras lets you take control and make the decision of what's best for each shot.Telephoto
There's nothing that indicates a serious photographer like the big barrel of a Sigma telephoto lens for Pentax cameras. A long eye brings the world closer to you so you can snap great shots even from a distance. The one thing to remember is that even as your distance increases, your field of view decreases.Wide Angle
The opposite of a telephoto lens is a wide angle lens. Best used for things like landscapes, a wide angle gives you a larger field of view than you would get with other Sigma lenses for Pentax cameras. These lenses also help you differentiate the background and foreground, making background objects appear much smaller than they would otherwise.Macro
Part of the beauty of photography is that it lets you see common objects in new ways. A macro lens is designed for extreme close ups, being able to focus an object at full size on the sensor. This allows for extreme detail, and a view of perspective that you simply cannot get with the unaided eye.