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Activating "raw sum"

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Activating "raw sum"
« on: 20 / January / 2013, 08:53:43 »
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I want to make a test image that requires more than the maximum 64 seconds of exposure.
So I made a simple script that take 4 images when I press the shutter once, and enabled RAW.

In CHDK's menu, I went to Miscellaneous Stuff/File Browser and located the 4 large files with .DNG extention.
I marked them all with the right arrow and then pressed the left arrow which gave me a popup menu.
In that menu i selected Raw ops, placed the marked line on "RAW sum" and finally hit the FUNC SET button, expecting the four selected files to be summed up and written to a new raw file. Instead, it just closes the popup menu   :blink:

Am I supposed to press another button? Work with some other type of raw file than DNG?
There is plenty of space on the card for the new file.
[Canon A3200IS,  CHDK 1.1.0-2401-0]

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Offline msl

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Re: Activating "raw sum"
« Reply #1 on: 20 / January / 2013, 09:33:26 »
This feature works only with RAW files not with DNG files.

See also RAW Merge, RAW Sum, RAW Average => http://chdk.wikia.com/wiki/CHDK_User_Manual#File_browser
CHDK-DE:  CHDK-DE links

Re: Activating "raw sum"
« Reply #2 on: 20 / January / 2013, 09:44:50 »
Work with some other type of raw file than DNG?
Disable saving as DNG - you need a plain RAW file to do this.  CHDK RAW is just an image sensor dump - easy to add images.  DNG contains format information in its header.
Ported :   A1200    SD940   G10    Powershot N    G16

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Offline nafraf

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Re: Activating "raw sum"
« Reply #3 on: 20 / January / 2013, 09:50:50 »
I want to make a test image that requires more than the maximum 64 seconds of exposure.
It seems to be a bug. exp_drv_task is implemented, but there is not EXT_TV_RANGE in platform_camera.h

What is the firmware version of your camera? It is necessary to create a version for test.


Re: Activating "raw sum"
« Reply #4 on: 20 / January / 2013, 17:23:22 »
Alright, switching off DNG and making new shots resulted in raw files that could be added with "raw sum", but those files could not be imported into Gimp's ufraw module for later processing.

Is there are way to convert CHDK raws into DNGs (either in the camera or on the computer)?   
googling suggested "dng4ps2", but it claims to not work with 64-bit linux, which is of course what I'm running.

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Offline reyalp

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Re: Activating "raw sum"
« Reply #5 on: 20 / January / 2013, 17:40:42 »
You might be better off shooting DNG and using software on your PC to do the summing. imagemagick or netpbm can be used to sum images. If you want to sum the bayered images you can use dcraw to convert the image to something like a 16 bit tif or ppm, sum with above mentioned tools, then de-bayer on the resulting image.

If you want to convert CHDK raw to something other tools will digest (pgm or 16 bit raw data), you can use rawconvert from the chdk source tree http://chdk.wikia.com/wiki/CHDK_Tools#rawconvert.c

You could also run dng4ps2 in wine (maybe, I haven't tried it) or a vm.
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Re: Activating "raw sum"
« Reply #6 on: 22 / January / 2013, 16:19:44 »
Thank you for the useful hints.  I found that dcraw could turn CHDK's DNG files into ppm files which have a very simple format and can be processed in gimp.

 

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