(in-package #:photo)
-(defun coc (imager-size &key (lpm 5) (minimum-distance 250)
+(defun sort-size (size)
+ "Returns a cons pair with the smaller size first."
+ (if (>= (car size) (cdr size))
+ (cons (cdr size) (car size))
+ (cons (car size) (cdr size))))
+
+(defun print-magnification (imager-size print-size)
+ "Returns the magnification required between an imager and print sizes
+while taking crop into consideration."
+ (setf imager-size (sort-size imager-size))
+ (setf print-size (sort-size print-size))
+ (float (max (/ (car print-size) (car imager-size))
+ (/ (cdr print-size) (cdr print-size)))))
+
+(defun coc (imager-size &key (lpm 5) (minimum-distance 250)
(viewing-distance 250)
(print-size (output-dimensions :8x10in)))
- "Returns circle of confusion in mm and print magnification for a format.
+ "Returns circle of confusion in mm and print magnification for a format.
Default resolving power is 5 lpm at 25cm."
+ (let* ((magnification (print-magnification imager-size print-size))
+ (resolution-factor (/ (* magnification lpm minimum-distance) viewing-distance))
+ (coc (/ 1.0d0 resolution-factor)))
+ (values coc magnification)))
- (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)))
-
-(defun coc-format (format &key (lpm 5) (minimum-distance 250)
+(defun coc-format (format &key (lpm 5) (minimum-distance 250)
(viewing-distance 250)
(print-size (output-dimensions :8x10in)))
- "Returns circle of confusion in mm and print magnification for a format.
+ "Returns circle of confusion in mm and print magnification for a format.
Default resolving power is 5 lpm at 25cm."
(let* ((format-size (imager-dimensions format))
(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 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))
+Circle of confusion can either be a number or keyword designating format.
+Reference: http://www.vanwalree.com/optics/dofderivation.html"
+ (let* ((aperture (/ focal-length f-stop))
(numerator-1 (* (- pupil-factor 1) (- distance focal-length)
coc focal-length))
(numerator-2 (* pupil-factor aperture focal-length distance))
(mag (float (/ focal-length (- distance focal-length))))
(infinity-blur-diameter (/ (* mag focal-length) f-stop))
(depth (- far near)))
+ (when (and (< far 0) (> distance focal-length))
+ (setq far most-positive-short-float)
+ (setq depth most-positive-short-float))
(values near far depth mag infinity-blur-diameter)))
;; Simplified calculation for symmetric lens
(defun dof-symmetric-mm (focal-length f-stop distance coc)
"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,
+near point, far point, total dof, near point, far point, magnification,
blur size at infinity (mm).
-Circle of confusion can either be a number or keyword designating format.
-Pupil factor is the ratio of the exit to enterance pupil diameters."
+Circle of confusion can either be a number or keyword designating format."
(let* ((aperture (/ focal-length f-stop))
(numerator (* distance coc (- distance focal-length)))
(factor-1 (* focal-length aperture))
(factor-2 (* coc (- distance focal-length)))
(near (- distance (/ numerator (+ factor-1 factor-2))))
(far (+ distance (/ numerator (- factor-1 factor-2))))
- (mag (magnification focal-length distance))
+ (mag (magnification :focal-length focal-length :object-distance distance :units :mm))
(infinity-blur-diameter (/ (* mag focal-length) f-stop))
(depth (- far near)))
+ (when (and (< far 0) (> distance focal-length))
+ (setq far most-positive-short-float)
+ (setq depth most-positive-short-float))
(values near far depth mag infinity-blur-diameter)))
(defun dof (focal-length f-stop distance coc &key (units :mm) (pupil-factor 1))
"Returns the Depth of Field.
-Input: FOCAL-LENGTH, F-STOP, DISTANCE, CIRCLE-OF-CONFUSION.
+Input: FOCAL-LENGTH, F-STOP, DISTANCE, CIRCLE-OF-CONFUSION.
Output: NEAR-POINT, FAR-POINT, TOTAL-DOF, MAGNIFICATION, BLUR-SIZE-OF-INFINITY-POINT-IN-MM."
(multiple-value-bind (near-point far-point total-dof mag blur)
- (dof-mm focal-length f-stop (length->mm distance units) coc
+ (dof-mm focal-length f-stop (length->mm distance units) coc
:pupil-factor pupil-factor)
(values (mm->length near-point units)
(mm->length far-point units)
(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)))
+