UBASIC/Scripts/CanonA640: ISO Bracketing

ISO Bracketing

Written for/on: Canon A640

Also works on: Other Canon AXXX (Not tested), Canon A590IS

ISO Bracketing by Johan Van Barel (http://www.vanbarel.com)

The purpose is to create a High Dynamic Range (HDR) image from a set of images taken at different ISO settings.

This script can be very useful in low-light conditions where you need to flash, however it will reveal extra information from the higher ISO images, when you combine the flash-image together with the higher ISO non-flash images.

The script takes 4 images without flash at iso 800, 400, 200, 100 and one image at iso 80 with flash on. You can later select the best images and stitch them together with a program like Photomatix (http://www.hdrsoft.com/index.html)

Documentation/Help (save as a small ISOBracket.txt" file to your /CHDK/SCRIPTS/ folder)

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Select P or C mode on your Canon A640 and select ISO 80 /(ISO AUTO for A590).

Make sure that Slow Synchro is On and the flash is set to Off.

Make sure that if you press the Func Set button, the ISO item is selected, but leave the function menu!

Parameters:

• Initial Delay (Sec)(Default=1)

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Script Code (save as "ISOBracket.bas" to your /CHDK/SCRIPTS/ folder)

rem Johan Van Barel 23-07-2007
rem ISO-Bracketing+Flash for Canon A640

@title ISO Bracket (Set ISO 80, Flash Off)
@param a Initial Delay (Sec)
@default a 1

if a<0 then let a=0

sleep a*1000

rem Set Iso 800
click "set"
sleep 400
click "right"
sleep 200
click "right"
sleep 200
click "right"
sleep 200
click "right"
sleep 200

print "Pic 1 at ISO 800"
shoot
click "left"
print "Pic 2 at ISO 400"
shoot
click "left"
print "Pic 3 at ISO 200"
shoot
click "left"
print "Pic 4 at ISO 100"
shoot
click "left"

rem Set Flash On
click "set"
sleep 400
click "up"
sleep 400
click "up"
sleep 400
print "Pic 5 at ISO 80 + Flash"
shoot

rem Set Flash Off
sleep 200
click "up"

rem Flash is now Off and ISO at 80
end

For Canon A590

Script Code (save as "ISOBracket.bas" to your /CHDK/SCRIPTS/ folder)

rem Johan Van Barel & Fulger06 25-04-2009
rem ISO-Bracketing+Flash for Canon A590

@title ISO Bracket (Set ISO Auto, Flash Off)
@param a Initial Delay (Sec)
@default a 1

if a<0 then let a=0

sleep a*1000

rem Set Iso 800
click "set"
sleep 400
click "right"
sleep 200
click "right"
sleep 200
click "right"
sleep 200
click "right"
sleep 200
click "right"
sleep 200
click "right"
sleep 200

print "Pic 1 at ISO 800"
shoot
click "left"
print "Pic 2 at ISO 400"
shoot
click "left"
print "Pic 3 at ISO 200"
shoot
click "left"
click "left"
print "Pic 4 at ISO 100"
shoot
click "left"
click "set"

rem Set Flash On
click "up"
sleep 400
click "up"
sleep 400
click "up"
sleep 400
print "Pic 5 at ISO 80 + Flash"
shoot

rem Set Flash Off
sleep 400
click "up"
sleep 400
click "up"

rem Flash is now Off and ISO at 80
sleep 400
end