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Timelapse with variable shutter speed

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Re: Timelapse with variable shutter speed
« Reply #130 on: 27 / July / 2008, 11:43:56 »
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In my case the tweak you gave me by introducing an extra sleep100 works, i don't know what it does but it works!

Thanks again for the script fbonomi!
S3 IS
450D & 18-55mm, 100-400mm

Re: Timelapse with variable shutter speed
« Reply #131 on: 27 / July / 2008, 14:57:51 »
It works :) big thanks to you for this amazing script :D
« Last Edit: 27 / July / 2008, 16:53:24 by Deeppy »

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Offline fbonomi

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    • Francesco Bonomi
Re: Timelapse with variable shutter speed
« Reply #132 on: 28 / July / 2008, 00:06:37 »
good!
I will integrate this change in the "official" version

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Offline topshot

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Re: Timelapse with variable shutter speed
« Reply #133 on: 29 / July / 2008, 09:03:25 »
I've not had any problem with the delays yet from what you gave fpalangie using an A620. I added in the overexposure compensation Bruce Allen had done. Here is the end portion of what I have been using (rayma is just my username so I can find my changes quickly):

Code: [Select]
rem added these 2 lines to reduce overexposure - rayma
L=L-25
M=M+25

rem added this line as there seems to be a bug (black pic) if M=0 - rayma
if M=0 then
 M=1
endif

rem we can now shoot
sleep 100
set_sv96 L
sleep 100
set_tv96_direct M
sleep 100
shoot
sleep 100
rem let's read histogram of the shot that was just taken
rem exp_get_info 100 800 h - rayma this is replaced by next line when using collabuild
h=get_histo_range 100 800
rem h contains the percentage of pixels that are between 100/1024 and 800/1024

rem exp_get_info 0 250 j - rayma this is replaced by next line when using collabuild
j=get_histo_range 0 250
rem j contains the percentage of pixels that are between 0/1024 and 250/1024

print "SHOOT ",p,M,L,h,j

p=p+1

goto "loop"
I also turn off my display before the loop to save battery power.

I've been pretty pleased with the videos I've made with those mods. I wish I wasn't in the city so I could get some decent star shots.


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Offline fbonomi

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Re: Timelapse with variable shutter speed
« Reply #134 on: 31 / July / 2008, 17:42:48 »
thanks all for the improvements and fixes.
I will soon (next few days) publish an updated version.

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Offline topshot

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Re: Timelapse with variable shutter speed
« Reply #135 on: 31 / July / 2008, 17:51:10 »
No problem. You did all the hard work.

BTW, this is the display off command and other collabuild mod needed:
Code: [Select]
rem added this to turn off display & save batts - rayma
click "display"

rem - rayma this line is added when using collabuild
shot_histo_enable 1
:loop
I always have my display showing the maximum options so only one click command is needed to turn it off. You would need two of those lines if you're showing the minimum options on the LCD.

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Offline topshot

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Re: Timelapse with variable shutter speed
« Reply #136 on: 01 / August / 2008, 18:16:37 »
I was able to finally do another sunset tonight, but I still have the same issue as before, and which you also experienced, even though I've added in some overexposure compensation. The problem stems from the h values being too high, which kicks in the overexposure protection once guess mode starts.

Shouldn't h be decreasing as the sun goes down? Mine stays the same (45-50) and in fact actually increased just a bit to over 60 by the time guess mode started.

Here is my video.
 .
The sun had just set a few minutes prior when I started and it runs for 65 minutes (condensed to 51 s).

I attached the debug file - I modified the format slightly to make sorting by shot easier. Guess mode starts at -175 because of the overexposure compensation I added.

Re: Timelapse with variable shutter speed
« Reply #137 on: 02 / August / 2008, 13:40:48 »
Hey guys...

First I would just would like to say wicked script!!  I found that this script takes better pictures than I do ;-)  Gave me new enjoyment out of my S5!!

I made a movie using ImageSalsa and Windows Media Encoder 9

http://www.gravelroads.ca/weather/WindowCanon4.wmv

Sunset4
Delay is set to           15
Limit Tv                  -480
Default Sv               384
Limit Sv                  768
Guess mode limit    -200
Slope in Guess mode 5


I have a couple of questions

1. How do I reduce the noise in the pics at the end of the video?  Obviously it is dark with high ISO.  Would setting the ISO lower work better?  How low can I go with it working?

2. Does the Sunset10 script work well enough to use yet?

3. Has anyone tried the power adapter for the S5?  Batteries are a pain to keep changing every 4 hours ;-)

Thanks fbonomi

I have made other videos using a webcam but never had anything that had a good resolution.  ImageSalsa has some nice features that allow for using a large number of photos and being able to use specific time frames and control how many pics/min/hour if you want.  Very worthy software...

http://www.gravelroads.ca/weather/Window07182008.wmv

Fahlcor


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Offline fbonomi

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Re: Timelapse with variable shutter speed
« Reply #138 on: 03 / August / 2008, 04:21:30 »
basically, the setting you had were:

Sunset4
Delay is set to           15:  15 seconds delay between each photo

Limit Tv                  -480: Longest exposure is 32 seconds
Default Sv               384: ISO starts at about 80
Limit Sv                  768: going up to about 1200

The final shots in youer movie are probably with ISO 1200, and that explains the noise..

The only way to keep noise down is to have lower ISO and longer exposures. The problem with going to longer exposures is that you have movements getting faster and faster in the video.

For example, if you have clouds, and you start with a delay of 15", in the day you have for example 15" of delay, 1/100th seconds of exposure, 15" delay, 1/100th seconds of exposure, etc...

if the exposure gets longer, you get for example: 15" of delay, 32" of exposure, 15" delay, 32" of exposure, etc. This means that the overall delay between photos in more than three times, and therefore the resulting speed of clouds in the video is three times faster.

If there aren't clouds, anyway, you can have higher exposure without annoying effects.

Sunset10: if you are doing sunsets, just stick to version 4, you won't get anything better.


Re: Timelapse with variable shutter speed
« Reply #139 on: 03 / August / 2008, 06:02:45 »
For the exposure length issue is there a way to tell the script that if the Tv is longer than the Delay then use 0?

Do any of the counting schemes you have in other scripts count using the actual time instead of between shots?  I realize that if the long exposure has pushed you past time interval but at least that would not be waiting for exposure time+prossecing time+delay.  If the exposure time is longer than the  Tv then at least it would shorten that loop.

Thanks again

Fahlcor

 

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