This Phase One LEE SW150 Mark I Filter Kit is designed to allow for the convenient use of 150mm-wide, 2mm-thick filters, including a supplied LEE Filters 150 x 170mm Soft-Edge Graduated Neutral Density 0.6 Filter, with a separately-available Schneider Kreuznach 28mm LS f/4.5 Aspherical Lens without vignetting.
The SW150 Mark I Filter Holder System within this kit that provides the ability to mount a filter in front of a Schneider Kreuznach 28mm LS f/4.5 Aspherical Lens consists of four main components, a filter holder, a front ring, a compression ring, and a locking ring. Together, those rings form an adapter specifically for the Schneider Kreuznach 28mm LS f/4.5 Aspherical Lens and the filter holder. Installation of the SW150 Mark I Filter Holder System onto the lens is easily completed by first sliding the front ring over that lens's integrated hood with the front ring's integrated lugs positioned away from the lens body. The compression ring can then be slid over the rear of the lens until it meets the front ring. The locking ring is then slid over the rear of the lens until it can be screwed into the front ring. After that is accomplished, the filter holder can then be placed over the assembled adapter from the front of the Schneider Kreuznach 28mm LS f/4.5 Aspherical Lens for use.
Once the filter holder is installed, a locking screw on the holder helps provide a reliable, yet adjustable connection that allows the holder to be rotated 360°, permitting the use of graduated neutral density and other filters that are enhanced by varied positioning.
The filter holder comes assembled with one pair of filter spacers installed in order to accept one 150mm-wide, 2mm-thick filter. A second pair of filter spacers as well as a set of screws is included to allow the filter holder to accommodate up to two 150mm-wide, 2mm-thick filters. Alternatively, a separately-available pair of spacers is available which can be used to modify the filter holder to use up to one 150mm-wide, 4mm-thick filter. On the rear of the filter holder are washers which all together provide raised surfaces to connect two included baffles. These baffles are intended to help prevent stray light from coming in between a filter and the lens behind it, which could otherwise result in reflections between a Schneider Kreuznach 28mm LS f/4.5 Aspherical Lens's front element and the side of the filter directly in front of it.
If using the 10-stop LEE Filters 150 x 150mm SW150 Big Stopper Neutral Density 3.0 Filter or the 6-stop LEE Filters 150 x 150mm SW150 Little Stopper Neutral Density 1.8 Filter, a LEE Filters SW150 Lightshield may also be purchased to more effectively use either of those separately-available filters along with the filter holder. Those filters each feature a built-in gasket that works with a LEE Filters SW150-series filter holder with an integrated or add-on Lightshield to help form a seal that is intended to prevent stray light, which could have unwanted effects on exposure, from coming in between a Big Stopper neutral density filter and the lens behind it.
A LEE Filters SW150 Lightshield installs onto the included filter holder by snapping into holder's pair of accessory slots located behind the first or only pair of filter spacers installed on it.
The included LEE Filters 150 x 170mm Soft-Edge Graduated Neutral Density 0.6 Filter helps to darken specific areas of an image, such as bright skies, while allowing for a normal, unaffected exposure in the other regions of the image. Where its coloration is most pronounced, the filter's density features a 4x filter factor that darkens the corresponding area of an image by 2 stops. The filter is densest at the edge and tapers to clear by the middle, with a soft-edged line of transition between the dense and clear areas. This filter is non-coated and is constructed from optical-quality resin for clarity as well as color fidelity.
An 11 x 11" cleaning cloth is provided to help remove dust, oil smudges, or dirt from the filter. For protection of the Schneider Kreuznach 28mm LS f/4.5 Aspherical Lens while it is not in use, a neoprene lens cap that can accommodate that lens's integrated hood and curved front element is also included.