Lens system
| Closest focusing distance |
0.135 m |
| Number of diaphragm blades |
6 |
| Diagonal angle of view (max) |
180 ° |
| Maximum aperture number |
22 |
4.5mm f/2.8 EX DC HSM Circular Fisheye PENTAX
Digitally optimised circular fisheye lens designed exclusively for digital SLR cameras with an APS-C size image sensor.
This auto focus circular fisheye lens has an angle of view of 180 degrees in all directions. It is exclusively designed for digital SLR cameras with the APS-C size image sensor. When used in conjunction with digital SLRs with APS-C size image sensors, it produces circular image within the frame.
F2.8 maximum aperture
The fast f/2.8 maximum aperture produces a bright image in the viewfinder making this lens ideal for low light photography.
Close-up Photography
This circular fisheye lens has a minimum focusing distance of 13.5cm and a maximum magnification of 1:6 making it particularly useful for close-up photography.
Excellent optical performance
SLD (Special Low Dispersion) glass provides effective compensation of chromatic aberration and Sigma’s Super Multi-Layer coating minimises flare and ghosting.
High speed auto focus
It is equipped with an inner focusing system that creates high definition and excellent image quality over the whole frame. The HSM (Hyper Sonic Motor)ensures fast and quiet autofocusing and allows full-time manual focus override by rotation of the focus ring.
Ideal for panoramic and scientific applications
This lens is ideal for photographers using computer stitching software which requires circular fisheye images to be input, resulting in stitched panoramas. 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.
