About the product Sigma 8mm F3.5 EX DG Circular Fisheye Lens is a large aperture F3.5 circular fisheye lens with close up capability optimized for use with digital SLR cameras. This circular fisheye lens produces circular images with an angle of view of 180 when attached to a full-frame digital SLR or 35mm film SLR camera. It has a fast maximum aperture of F3.5 and 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. *Full circle can only be captured with full frame 35mm format digital SLR and film SLR cameras. Auto-focus system This circular fisheye lens produces circular images with an angle of view of 180 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. F3.5 maximum aperture This lens is perfectly suited for low light conditions indoors or at dusk. Close-up Photography This circular fisheye lens has a minimum focusing distance of 13.5cm (5.3 ) and a maximum magnification of 1 4.6 making it particularly useful for close-up photography. Excellent optical performance Special Low Dispersion (SLD) glass offer effective compensation of color aberration. Reduction of flare and ghosting Sigma s super multi-layer lens coating reduces flare and ghosting a common problem with digital cameras and also creates an optimum color balance. An ideal lens for scientific applications Due to the quantifiable angle/area relationship it produces this lens can be used for scientific applications such as solid angle measurements of cloud distribution over the sky or vegetation distribution of the rain forest canopy. Gelatin Filter Holder A holder at the rear of the lens accepts gelatin filters. Detailed specifications of the Sigma 8mm F3.5 EX DG Circular Fisheye Lens Lens Construction 11 Ele. Product details Price $869.00 Brand Sigma SKU 29938 Shipping cost $19.00 UPC 000467854000.