A Fisheye lens has an extremely wide angle that takes in a very broad, hemispherical image, lending a neat little “round” effect to things. To do this, however, it utilizes a hemispherical shape

All cameras have lenses , they’re what gets the world ‘out there’ funneled into your camera as an image, one that can then be imprinted onto film or a digital sensor or whatever. A Fisheye lens has an extremely wide angle that takes in a very broad, hemispherical image, lending a neat little “round” effect to things. To do this, however, it utilizes a hemispherical shape, similar to the eye of a fish, in order to capture an extensive radius. When viewing the printed image, the center will appear close to normal but the outer elements will appear very distorted.

1、Use a fisheye lens for special architectural effects when capturing a large building. Try composing the frame with an image in the foreground and use the sloping background to enhance the theme. For instance, using a fisheye lens when shooting a tulip field in Holland adds interest when foreground flowers feature prominently and a quaint windmill farm frames the background.

2、Compose your image with a straight line only in the middle. Because the fisheye lens distorts anything off center in the frame, the only lines that will appear perfectly straight are those in the exact middle. Any lines falling above or below the exact center will appear distorted and the further away the line travels from the center, the greater the distortion.

3、Zoom out to increase the circular distortion in your image. At full extension, the fisheye lens creates a round image, drawing side elements inward and compressing the outside elements in the circle.

4、Reduce the focal length to use the fisheye lens as a wide-angle lens. The shorter the focal range, the less distortion your image will portray. When zoomed all the way in, your fisheye lens can double for a wide-angle lens, but you will still have some barrel distortion towards the perimeter of the image.

DIY Fisheye Lens for a SLR

Get a pair of old glasses, the type for far-sighted people ("reading glasses").

If you don't have an old pair, buy an inexpensive pair from the drug store. The glasses need to be in the + numbers. The thicker the lens the better, and the more of a "fisheye" effect you'll get.

Remove a lens from the frames. The lens should pop out by gently wiggling the frames.

Duct tape the top and bottom of the glass lens to the camera lens. Do not tape the side because it will wreck the "wide angle" effect.