Bright images 1 Center detection 1 Dark image 1 Euclidean Distance 1 Euclidean distance 1 Image conditions 1 MATLAB 1 Pupil Distance 1 Pupil centers 1 Pupil distance 1 Radial Symmetry Transform 1 Radial symmetry transforms Refractive error 1 Self Quotient Image 1 Self-quotient image 1 Uncertainty analysis 1