X-Git-Url: http://git.kpe.io/?a=blobdiff_plain;f=dof.lisp;h=11f158c77457b591d43f94e75abd89e6a70eb4f7;hb=a8fb6b568b815cecb970442af816cc95fe97dc14;hp=4117c5a0f7d703dacce30a0e2cd51315c211945f;hpb=3c1c551f36fe090936bf5d21e7eb65acbcc0d457;p=cl-photo.git diff --git a/dof.lisp b/dof.lisp old mode 100755 new mode 100644 index 4117c5a..11f158c --- a/dof.lisp +++ b/dof.lisp @@ -25,13 +25,14 @@ "Returns circle of confusion in mm and print magnification for a format. Default resolving power is 5 lpm at 25cm." - (let* ((imager-diagonal (diagonal (car imager-size) (cdr imager-size))) - (print-diagonal (diagonal (car print-size) (cdr print-size))) - (resolution-factor (/ (* lpm print-diagonal minimum-distance) - (* imager-diagonal viewing-distance))) - (coc (/ 1.0d0 resolution-factor)) - (print-magnification (/ print-diagonal imager-diagonal))) - (values coc print-magnification))) + (let* ((imager-max (max (car imager-size) (cdr imager-size))) + (imager-min (min (car imager-size) (cdr imager-size))) + (print-max (max (car print-size) (cdr print-size))) + (print-min (min (car print-size) (cdr print-size))) + (magnification (max (/ print-max imager-max) (/ print-min imager-min))) + (resolution-factor (/ (* magnification lpm minimum-distance) viewing-distance)) + (coc (/ 1.0d0 resolution-factor))) + (values coc magnification))) (defun coc-format (format &key (lpm 5) (minimum-distance 250) (viewing-distance 250) @@ -49,25 +50,34 @@ Default resolving power is 5 lpm at 25cm." (values coc print-magnification))) (defun coc-pixels (imager pixels) - "Returns circle of confusion based on pixel size." + "Returns lpm and circle of confusion based on pixel size." (when (and (consp imager) (consp pixels)) - (values (float (* 2 (/ (car imager) (car pixels)))) - (float (* 2 (/ (cdr imager) (cdr pixels))))))) + (let ((coc-w (float (* 2 (/ (car imager) (car pixels))))) + (coc-h (float (* 2 (/ (cdr imager) (cdr pixels)))))) + (values coc-w coc-h (/ 1. coc-w) (/ 1. coc-h))))) (defun coc-pixels-format (format) "Returns circle of confusion based on pixel size." (coc-pixels (imager-dimensions format) (pixel-dimensions format))) -(defun coc-airy (f-stop) +(defun coc-airy (f-stop &optional (wavelength 0.000512)) "Return the circle of confusion based on the airy disk." - (let ((airy (/ f-stop 1500))) - (float (* 2 airy)))) + (float (/ 1 (rayleigh-limit f-stop wavelength)))) + +(defun rayleigh-limit (f-stop &optional (wavelength 0.0005)) + "Returns the rayleigh limit in line pairs per mm (MTF 9%) as well as the MTF50" + (let ((rayleigh (float (/ 1 1.22 f-stop wavelength)))) + (values rayleigh (* 0.46 rayleigh)))) + +(defun maximum-sharpness-aperture (format &optional (wavelength 0.0005)) + (multiple-value-bind (coc-w coc-h lpm-w lpm-h) (coc-pixels-format format) + (declare (ignore coc-w coc-h)) + (/ 1. (* 1.22 wavelength (/ (min lpm-w lpm-h) 0.46))))) (defun dof-mm (focal-length f-stop distance coc &key (pupil-factor 1)) "Returns depth of field based on focal-length, f-stop, distance, and coc. Six values are returned: -near dof, far dof, total dof, near point, far point, magnification, -blur size at infinity (mm). +near point, far point, total dof, magnification, blur size at infinity (mm). Circle of confusion can either be a number or keyword designating format." (let* ((aperture (/ focal-length f-stop)) (numerator-1 (* (- pupil-factor 1) (- distance focal-length) @@ -120,3 +130,7 @@ Output: NEAR-POINT, FAR-POINT, TOTAL-DOF, MAGNIFICATION, BLUR-SIZE-OF-INFINITY-P (defun effective-aperture (focal-length distance aperture) (* aperture (bellows-factor focal-length distance))) + +(defun mtf-scanner (freq dscan-freq &optional (order 3)) + (abs (expt (kmrcl:sinc (* pi (/ freq dscan-freq))) order))) +