Sigma 8mm F3.5 EX DG Circular Fisheye Lens

This circular fisheye lens produces circular images with an angle of view of 180-degrees when attached to a full-frame digital or 35mm film SLR camera. It has a maximum aperture of f3.5, a minimum focusing distance of 5.5-inches and a maximum magnification of 4.6x. 
The special fisheye design allows maximum creative expression. Sigma's super multi-layer lens coating reduces flare and ghosting, a common problem with digital cameras. The new lens power layout reduces color aberrations. Providing excellent image quality for digital and film SLR cameras. 
This lens can be used for the scientific applications such as the solid angle measurements of cloud distribution over the sky, the vegetation distribution of the rain forest canopy, etc., due to the quantifiable angle/area relationship it produces. This lens has a gelatin filter holder at the rear, allowing the use of gelatin filters. These are large-aperture lenses with wide angles and short minimum focusing distances. 
With an abundance of peripheral illumination, they are ideal lenses for digital SLR cameras whilst retaining suitability for traditional 35mm SLRs. This circular fisheye lens produces circular images with an angle of view of 180 degrees when attached to a full-frame digital SLR or 35mm film SLR camera. 
It has a minimum focusing distance of 13.5cm (5.3"). Sigma's super multi-layer coating and Special Low Dispersion (SLD) glass provide excellent image quality for digital and film SLR cameras. The special fisheye design allows maximum creative expression.This circular fisheye lens produces circular images with an angle of view of 180 degrees and also incorporates an auto focus system to achieve accurate focusing that might be difficult through the camera's viewfinder due to the extremely large depth of field. This lens is perfectly suited for low light conditions indoors or at dusk.

Key Features
- Improved version offers a brighter f/3.5 aperture
- Circular fisheye lens can be used to create circular images with an angle of view of 180°
- Improved DG lens design corrects for various aberrations
- Useful for academic/technical applications such as solid angle measurements