The Rodenstock Digital Center Filter for HR Digaron-W 32mm f/4 Lens helps to compensate for light falloff by providing 2.5 stops of concentric graduated neutral density in the center of the filter that tapers off to clear by the edges in order to produce even overall exposure with that wide-angle lens.
Opposed to traditional application of an evaporated dark layer of density, this filter employs a secondary gray glass in order to produce the filter's density without the repercussions of contrast-reducing stray light or ghost images being created. Additionally, an MC coating has also been applied to both surfaces of the filter in order to further reduce surface reflections for clearer, sharper, and more color-neutral imagery.
The 86mm threaded filter features an oversized front thread diameter of 105mm to further prevent vignetting.
- Optimized specifically for the Rodenstock HR Digaron-W 32mm f/4 lens, this filter helps to compensate for the inherent light falloff of that wide-angle lens.
- A secondary gray glass is employed, versus a traditional vapor-deposited dark coating, in order to maintain image clarity, contrast, and color neutrality by reducing the likelihood of surface reflections and ghosting.
- A dual cemented lens construction, incorporating one neutral gray planoconvex lens and one transparent planoconcave lens, helps to maintain the same refractive index, along with the same dispersion characteristics, as a normal, homogenous, planoparallel glass plate. However, since the neutral gray (density) lens features a convex shape, it is able to provide concentrically graduated density from the center of the filter, lessening towards the edges.
- Multicoating has been applied to both surfaces of the filter in order to complement and further enhance the anti-reflective qualities of the unique filter design, including a reduction of veiling glare and surface reflections to produce color-neutral and contrast-rich imagery.
- An oversized filter ring helps to reduce vignetting while still enabling the attachment of subsequent filters if desired. The rear mounting threads measure 86mm in diameter, and the front threads measure 105mm in diameter.