Schneider Close Up Diopter Full +3 - 6 tum Round. Schneider Close-Up +3, close-up lens, are made of first-class optical glass and with the highest precision. The filter provides an increased degree of magnification and allows the photographer to work from longer distances while maintaining close-up. Select diopter power depending on the lens focal length, focus setting, object distance, and subject size. Both lens surfaces on the filter have Schneider's hard anti-glare coating, which minimizes light loss and unwanted optical effects. The filter is completely color-neutral and maintains the lens' image quality and contrast. Schneider's Diopter lenses are mounted in a black anodized aluminum ring. The construction is very wear-resistant and durable and keeps the filter lens in the exact position for maximum image quality.