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UBASIC/Scripts: HDR time lapse

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HDR time lapse

How to create an HDR timelapse movie

Generic script

Use the following script if your camera model supports bracketing (with fixed aperture and shutter settings).

Documentation/Help (save as a small "timelapse.bas" file to your /SCRIPTS/ folder)

@title Timelapse photo

@param a For HDR timelapse movie set:
@param b      JPG 640x480 + BKT
@param c .

@param m Interval (min) 
@default m 0 
@param s Interval (x10 sec) 
@default s 1 
@param t Number of takes 
@default t 300 
@param x Initial delay (sec) 
@default x 2 

if t<300 then t=300

i=60000*m+10000*s
if i<10000 then i=10000

if x<2 then x=2
sleep x*1000

for j=1 to t
    cls
    print "Photo take",j,"of",t 
    shoot
    print "   Waiting",m;":";s*10,"..."
    print " "
    sleep i
next j
end

Powershot S3 IS

Written for/on: Powershot S3 IS

One of the big problems with the S3 IS, is that you can only bracket off of metering, not off fixed settings. This means you cannot take several bracketed shots using the same exposure. I have found this very annoying when I try to take several HDR sets for either panoramic shots or time lapses. You could use a bracketing script that hits the button for each picture, but that is much slower than the built in bracketing, and the movement of clouds and such are much more noticeable in the HDR. So with a bit of experimentation I have created this script for HDR time lapses. You start it in Av mode and set up your bracketing using the cameras built in bracketing feature. The script will lock the exposure based using your metering, then will hit the button every a seconds using the same exposure settings. The 3 bracketed shots will go as fast as your camera would do them normally.

@title Shutter speed bracketing lapse
@param a Number of seconds between shots
@default a 10

print "Locking exposure"
press "shoot_half"
sleep 3000
for q=1 to 300
  print "Shoot ", q, " of 300"
  click "shoot_full"
  press "shoot_half"
  sleep a*1000
next q
release "shoot_half"
end


Putting it together

After you have your source jpg files (3 per frame if you are using built in S3 IS bracketing), follow the following steps:

1. Run HDR Artizen to batch your target frames (unfortunately if you want to use a different tone mapping you cannot use auxiliary HDR files created before and you need to merge source jpg files again)
2. Run XnView to easily rename the resulting target jpg files so their names are like 0001.jpg, 0002.jpg, etc...
3. Run VirtualDub. If you haven't heard of this wonderful program this probably your first movie. If you have done some video editinng before and you haven't tried VirtualDub your are either a rich victim of marketing brainwashing since you purchased all those proprietary solutions, or more probably you are a lazy regular person downloading the same programs for free. Once you try VirtualDub you will never get back to any of the big and slow "premium/professional" packages.
3.1 Select File->Open video file and select "image sequence"
3.2 Select first image and make sure the checkbox for piking up sequetial segments is on (that is why you renamed the files before)
3.3 Select Video->Full processing
3.4 Select Video->Compression and choose you favorite codec (e.g DivX for compatability with hardware players)
3.5 In the codec settings set 100% quality
3.6 Select Video->Frame rate and set 30 fps (or whatever your favorite)
3.7 Select File->Save as avi
3.8 Putting some music over is simple and you can figure out on your own (if you can't then please RTFM)

Enjoy!

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