;;;;
;;;; $Id$
;;;;
-;;;; This file, part of cl-photo, is Copyright (c) 2005 by Kevin Rosenberg.
-;;;; Rights of modification and redistribution are in the LICENSE file.
+;;;; This file, part of cl-photo, is Copyright (c) 2005 by Kevin M. Rosenberg
+;;;;
+;;;; cl-photo users are granted the rights to distribute and use this software
+;;;; as governed by the terms of the GNU General Public License v2
+;;;; (http://www.gnu.org/licenses/gpl.html)
;;;;
;;;; *************************************************************************
;; Based on http://www.photostuff.co.uk/dofmstr.htm
+(defun coc-format (format &key (lpm 5) (minimum-distance 250)
+ (viewing-distance 250)
+ (print-size (format-dimensions :8x10in)))
+ "Returns circle of confusion in mm and print magnification for a format.
+Default resolving power is 5 lpm at 25cm."
+
+ (let* ((format-size (format-dimensions format))
+ (format-diagonal (diagonal (car format-size) (cdr format-size)))
+ (print-diagonal (diagonal (car print-size) (cdr print-size)))
+ (resolution-factor (/ (* lpm print-diagonal minimum-distance)
+ (* format-diagonal viewing-distance)))
+ (coc (/ 1.0d0 resolution-factor))
+ (print-magnification (/ print-diagonal format-diagonal)))
+ (values coc print-magnification)))
+
+(defun coc-sensor (format nx ny)
+ "Returns circle of confusion based on pixel size."
+ (let* ((dim (format-dimensions format))
+ (pixel-width (/ (car dim) nx))
+ (pixel-height (/ (cdr dim) ny)))
+ (values (coerce (* 2 pixel-width) 'float)
+ (coerce (* 2 pixel-height) 'float))))
+
+(defun coc-sensor-camera (camera &key (format :aps))
+ (let ((dim (sensor-dimensions camera :format format)))
+ (coc-sensor format (car dim) (cdr dim))))
+
+(defun sensor-dimensions-megapixels (format megapixels)
+ (let* ((dim (format-dimensions format))
+ (aspect-ratio (/ (car dim) (cdr dim)))
+ (width (round (sqrt (* aspect-ratio 1000000 megapixels)))))
+ (cons width (round (/ width aspect-ratio)))))
+
+(defun sensor-dimensions (camera &key (format :aps))
+ (etypecase camera
+ (keyword
+ (ecase camera
+ ;; nikon
+ (:d2x (cons 4288 2848))
+ (:d2x (cons 2484 1242))
+ (:d70 (cons 3008 2000))
+
+ ;; canon
+ (:1d (cons 2464 1648))
+ (:1d2 (cons 3504 2336))
+ (:1ds (cons 4064 2704))
+ (:1ds2 (cons 4992 3328))
+
+ ))
+ (number
+ (sensor-dimensions-megapixels format camera))))
+
+(defun coc-airy-disk (f-stop)
+ "Return the circle of confusion based on the airy disk."
+ (let ((airy (/ f-stop 1500)))
+ (coerce (* 2 airy) 'float)))
+
(defun dof (focal-length f-stop distance coc)
"Returns depth of field as fives values:
-near dof, far dof, total dof, near point, far point"
+near dof, far dof, total dof, near point, far point.
+Circle of confusion can either be a number or keyword designating format."
(let* ((aperature (/ focal-length f-stop))
(numerator (* distance coc (- distance focal-length)))
(factor-1 (* focal-length aperature))
(values (* 0.001 near-dof) (* 0.001 far-dof) (* 0.001 total-dof)
(* 0.001 near-point) (* 0.001 far-point))))
-
(defun hyperfocal (focal-length f-stop coc)
(+ focal-length (/ (* focal-length focal-length) (* f-stop coc))))