The Samyang 8mm f/3.5 Ultra Wide-Angle Fisheye Lens for Pentax K Mount gives you a 180deg. view with dramatic, exaggerated perspective. With a hybrid aspherical lens and multi-layer coating, you can produce sharply defined images with a minimum of flare and ghosting. The 8mm lens focuses as close as 1' (0.30m) from the lens and has a built-in petal lens hood.
Reviewed by 2 customers
I use this lens on a Nikon D90 and a D7100. It is sharp sharp sharp!!! This is not an autofocus lens so just set the lens focus at 3' and leave it there. That ensures you get from very close all the way to infinity. If you're using a Nikon ...get the Samyang with the auto chip. I have mine set at f8 and it works perfectly.
Had some concerns about Manual Focus. Read some blogs on the lens. VERY impressed with how easy it is to use. 4 steps --- Set the lens on f=8.; and set the focus on infinity. And everything beyond one foot from the lens is in perfect focus. Set your camera on A (Aperture setting) and go into the Menu to allow the camera to operate as if there was no lens attached. And take awesome photos. I ignored the instructions that came with the lens; as I was intructed to do in some of the blogs. I use mine with a Sony a55 and a77. And don't forget to re-change your camera settings when you go back to regular lenses.