This WonderPana 145 Core Unit from FotodioX is designed to specifically fit the Sigma 12-24mm f/4.5-5.6 DG HSM II lens, as well as a separately available WonderPana 6.6" Holder Bracket. Those items can be combined to allow for the convenient use of two 2.5 to 4.0mm-thick filters measuring 6.6" wide, or one 2.5 to 4.0mm-thick filter measuring 6.6" wide, along with one FotodioX 145mm round filter behind it. A compatible 145mm circular polarizer filter and a 145mm inner-pinch lens cap for 145mm FotodioX round filters are also provided.
The included WonderPana 145 Core Unit consists of two components, a front filter holder and a rear lens collar. Placement of this 145 Core Unit onto a Sigma 12-24mm f/4.5-5.6 DG HSM II lens is easily accomplished by sliding the rear lens collar over the rear of the lens until it has achieved a secure fit. Afterwards, the front filter holder can be screwed onto the front of the installed rear lens collar.
So that a WonderPana 6.6" Holder Bracket can be used with this 145 Core Unit for a Sigma 12-24mm f/4.5-5.6 DG HSM II lens, pre-tapped threaded inserts along the edge of the front filter holder accommodate that holder bracket's six included brass short-screws. These screws ensure that a WonderPana 6.6" Holder Bracket's two assembly pieces are positioned parallel to each other and can hold a 6.6"-wide filter between them. Once that holder bracket and the front filter holder are combined, and the separate collar has been slid over the rear of a Sigma 12-24mm f/4.5-5.6 DG HSM II lens, the front filter holder with the attached holder bracket can be screwed onto the installed rear lens collar.
After being fitted onto a Sigma 12-24mm f/4.5-5.6 DG HSM II lens, the eight pre-tapped threaded inserts all around the edge of the WonderPana 145 Core Unit allow a WonderPana 6.6" Holder Bracket to be installed in 45° increments so that rectangular filters placed within it can be angled to the best approximate position relative to the subject in front of the camera. This helps to benefit the use of graduated neutral density and other filters that are enhanced by varied positioning.
This FotodioX WonderPana 145 Core Unit features an aluminum-alloy construction and includes front filter threads, which allow a FotodioX 145mm round filter to be used along with a separately available WonderPana 6.6" Holder Bracket. If a 145mm round filter is used on the attached WonderPana 145 Core Unit, the rectangular filter slot closest to the rear of the holder bracket becomes unavailable.
FotodioX 145mm Circular Polarizer Filter
The FotodioX 145mm Circular Polarizer Filter is compatible with the FotodioX WonderPana 145, FreeArc, and Absolute filter holder systems. It helps to reduce reflections as well as glare by filtering out light that has become polarized due to reflection from a non-metallic surface. The light from the sun naturally becomes partially polarized due to reflecting off electrons in air molecules, causing the light to scatter into what appears as haze. A polarizing filter arranges, and filters, this directionally polarized light perpendicularly to the reflected light, allowing for the absorption of much of this light. This results in a noticeable reduction of glare and reflections from non-metallic surfaces and an increase in the saturation of skies and foliage.
A circular polarizer only differs from a linear polarizer in that it contains a quarter wave plane in addition to the linear polarizing filter. The addition of this quarter wave plane is to circularly polarize the linearly polarized light for the use of auto focus and exposure functions. Due to how the light is broken down and filtered with a linear polarizer, auto focus and exposure accuracy become skewed during use. When the light becomes circularly polarized, it permits the use of these functions.
The FotodioX 145mm Circular Polarizer Filter is constructed from optical glass for clarity as well as color fidelity and features lightweight, aluminum-alloy filter rings. A rear filter ring connects to a compatible filter holder while four brass knobs along the side of the front filter ring allow the filter glass to be easily rotated. This provides the ability to achieve the desired degree of polarization even if another filter is placed in front of the FotodioX 145mm Circular Polarizer Filter.
FotodioX 145mm Center-Pinch Snap-On Lens Cap for Select WonderPana Systems and Filters
The 145mm Center-Pinch Snap-On Lens Cap for Select WonderPana Systems and Filters from FotodioX is a 145mm front lens cap with a squeeze, spring, and snap-on mechanism. It is easy to install as well as remove, and can attach to a WonderPana 145, FreeArc, or Absolute filter holder system in order to protect the front element of a lens that any one of those systems are mounted on. Additionally, this lens cap can be used to protect a non-ultra slim FotodioX WonderPana 145 filter that is mounted on a FotodioX WonderPana 145, FreeArc, or Absolute filter holder system and has no other filters placed in front of it.
Lens caps protect your lens or filter from scratches, fingerprints, and the elements when the lens or filter is not in use. It's always good to have a spare in your camera bag, too.