An optical system is provided for allowing regional focus control. The system uses a variable power optical component system as two optical shear plates that can be laterally displaced with respect to each other to adjust and alter the field curvature of the optical system. This changing of the field curvature creates an area of focus whose particular size and shape within the field of view is controlled through manipulation of the shear plates with respect to each other and the field of view. The area of focus can be repositioned to any point within the field of view so that the area of focus can affect the image light coinciding with that particular region. The shear plates are preferably positioned at the intermediate focal plane of the optical system, between the camera body and the taking lens. The image which has been altered, by the shear plates is then transposed to the camera body by a relay lens and recorded by film at the primary film plane located within the camera body. The end result is a optical system that is suitable for a camera wherein regional focus control is achieved, regardless of the depth of field of the camera taking lens or its aperture settings.