Patent ID: 7224849

Claim:
A method for determining an optimum gain response in a spatial frequency response correction for a projection system comprising the steps of: a) setting a code value to first code value; b) projecting a flat field image at said code value; c) capturing said flat field image with a camera; d) creating a defect map of defects in said flat field image; e) applying said defect map to said flat field image to form a corrected image; f) setting a gain table to a first gain for said corrected image; g) applying said gain table to said corrected image; h) registering said corrected image; i) filtering said registered image; j) measuring said filtered image for a standard deviation; k) determining whether all gains for producing an under corrected image and an over corrected image have been exhausted for said code value; l) if all gains have not been exhausted for said code value, set said gain table to said first gain plus n and go to step g), if all gains have been exhausted determine the optimum gain for said code value.