The Cokin X-Pro Incolor Center Spot 1 filter has a clear spot in the center and allow for the portrayal of an object in diffused surroundings. This filter only comes in grade #1 (070). It consists of a gray outer area. The portion outside of the image center will be reproduced less sharp than the center. This filter is commonly used in combination with color center spot filters for a more exaggerated effect. It is intended to be used with wide angle lenses. The filter effect is directly influenced by the f-stop and the focal length. The transformation is softer with wider apertures. The size of the clear circular area increases relatively with the selection of longer focal lengths.
The exposure determination should be done without the filter. If the camera has the capability of spot-metering, then one can measure with the filter in place.
This filter measures 130 X 170mm and only fits the Cokin X-PRO series holder.