Resolve discontinuity in 2D FRD residuals

Comparison between residuals between detector images in focus between two FRD values show noticeable jumps between the third and fourth row, as well as between the 5th and 6th column. While the jump between the third and fourth row is likely correlated with the large spatial distance between the wavelengths of the lines in the detector, there is no apparent reason why there should be such a jump between the 5th and 6th column. This raises the question of if there is an issue with previous analysis, and if so, how it effects previous results. This ticket is to determine what is causing the issue and address these concerns.