Nisha 49mm Split Field Filter

This Nisha Split Field Filter includes an aluminum-alloy filter ring that can mount onto a lens with 49mm front threads. Occupying half of the area within the filter ring is a close-up lens with a +2 strength diopter for use in achieving macro-like results. Close-up lenses are magnifiers that optically decrease the focal length of a camera lens they are placed on. This effect lessens the minimum focus distance between your camera lens and an object. Magnification can then be obtained while photographing an object by moving the front of the camera lens close to it. The magnifying power of a close-up lens is indicated by its diopter strength. A close-up lens with a higher diopter number provides more relative magnification and can be combined with other close-up lenses to increase or fine-tune its effect.

The other half of the area within the filter ring has no close-up lens element and is completely unobstructed, allowing a camera lens placed behind this filter to project an image where half of the frame is unmagnified. This provides the potential to place subjects magnified by the Nisha 49mm Split Field Filter within a discernible background, due to a close-up lens's secondary effect of only allowing a very shallow depth-of-field. The Nisha 49mm Split Field Filter can be effectively applied by lining up its close-up lens and the subject to be magnified with either the bottom or top front half as well as either the left or right half of the camera lens being used. The filter ring can then be rotated to orient the macro effect relative to horizon lines or specific background features. By also using a narrow aperture, the resulting wide depth of field can be captured by the remainder of the camera lens that is not affected by the filter's close-up lens. A foreground subject can then be magnified and simultaneously, some focus can be maintained on a background that would otherwise be rendered completely out of focus.