fstop.pl

#!/usr/local/bin/perl
use strict;
use warnings;

my $pi = 3.1415;
my $focDist = 700; #e.g. 10000mm = 1m Focus Distance
my $cropFactor = 1.6;
my $focLen = 24*1.6; #e.g. 50mm
my $actualFocLen = $focLen * $cropFactor;
my $fstop = 2.8; # 1, 1.4 , 2 , 2.8, 4, 5.6
my $diameter = getDiameterFromFstop();

my $coc = 0.018; #Circle of Confusion APS-C Canon -> 0.018 35mm -> 0.029
my $hfd = calcHyperFocalDistance($fstop,$coc,$focLen);
my $apertureArea = areaOfCircle($diameter);

my $nearDistance = nearDistance();
my $farDistance = farDistance();
my $dof = dof();

my $unit = "mm";

#aperture subs
sub areaOfCircle {
    return $pi * ($diameter/2);    
}

sub getDiameterFromFstop {
	return $focLen/$fstop;
}

sub getFstopFromDiameter {
	return $focLen/$diameter;
}

sub fStopUp {
	$fstop = $fstop*sqrt(2);
	$diameter = getDiameterFromFstop();
	$apertureArea = areaOfCircle();
	$hfd = calcHyperFocalDistance();
	printCamValues($fstop,$focLen,$hfd,$coc,$apertureArea,$diameter,"We changed the F/STOP one UP!");
	return $fstop;
}

sub fStopDown {
	$fstop = $fstop/sqrt(2);
	$diameter = getDiameterFromFstop();
	$apertureArea = areaOfCircle();
	$hfd = calcHyperFocalDistance();
	printCamValues("We changed the F/STOP one Down!");
	return $fstop;
}

sub changeFocLen {
	$focLen = $_[0];
	$diameter = getDiameterFromFstop();
	$apertureArea = areaOfCircle();
	$hfd = calcHyperFocalDistance();
	printCamValues("We changed the FOCAL LENGTH to",$focLen," ");
	return $focLen;
}

sub calcHyperFocalDistance {	
	return (($focLen*$focLen)/($fstop*$coc))+$focLen;
}

sub nearDistance {
	return ($focDist*($hfd-$focLen))/($hfd+$focDist-(2*$focLen));
}

sub farDistance {
	return ($focDist*($hfd-$focLen))/($hfd-$focDist);
}

sub dof {
	return $farDistance-$nearDistance;
}

sub unitConverter {

	if($_[0] eq "mm") {
		return sprintf("%.1f",$_[1]),"mm";
	} elsif ($_[0] eq "cm") {
		return sprintf("%.1f",$_[1]/10),"cm";
	} elsif ($_[0] eq "m") {
		return sprintf("%.1f",$_[1]/100),"m";
	} else {
		return sprintf("%.1f",$_[1]),"mm";
	}
}

sub printCamValues {
	print "\n";
	print "---------------------------\n";
	print $_[0],"\n";
	print "---------------------------\n";
	print "------------FOCUS----------\n";
	print "FOCUS DISTANCE: ",unitConverter($unit,$focDist),"\n";
	print "FOCAL LENGTH: ",unitConverter($unit,$focLen),"\n";
	print "HYPER FOCAL DISTANCE: ", unitConverter($unit,$hfd),"\n";
	print "\n";
	print "-------------DOF-----------\n";
	print "NEAR DISTANCE SHARPNESS ",unitConverter($unit, $nearDistance),"\n";
	print "FAR DISTANCE SHARPNESS ",unitConverter($unit, $farDistance),"\n";
	print "DOF SIZE ",unitConverter($unit, $dof),"\n";
	print "\n";
	print "----------APERTURE---------\n";
	print "FSTOP: F/",$fstop,"\n";
	print "CIRCLE OF CONFUSION: ",$coc,"\n";
	print "APERTURE AREA: ",unitConverter($unit, $apertureArea),"^2\n";
	print "APERTURE DIAMETER: ",unitConverter($unit, $diameter),"\n";
	print "---------------------------\n";
	print "\n";
}

printCamValues("CAMERA DEFAULT SET");

#fStopDown();
#fStopUp();
changeFocLen(70);
#fStopUp();
#fStopDown();