• The shorter the focal length, the more visible the zone. As for the transition from sharp to soft, it depends on the aperture: the wider it is, the more diffuse the transition will be. For a correct adjustment with auto-focus reflex cameras, the choice of an AF central collimator is obviously required. We also recommend working with apertures of ƒ/5.6 or ƒ/8 in order to keep a sufficiently blurry transitional zone. A strong backlight brightens the effect of the filter.
• Uncolored Center Spot filters create blur around the central subject in a completely natural-looking way, giving the subject prominence in the image.
• Grey and Colored Center Spot filters work by blurring and darkening the periphery of the image in a more or less noticeable way. The intensity and the quality of the central subject’s lighting are clearly emphasized.
• Oval Center Spot filters are made for larger or taller subjects.