Analyse light intensity via RAW image? - RAW Shooting and Processing - CHDK Forum

Analyse light intensity via RAW image?

  • 2 Replies
Analyse light intensity via RAW image?
« on: 27 / January / 2009, 07:45:51 »
I'm trying to use a 10-bit Canon A590 IS to analyse the difference in light intensity of different light-beams projected on a piece of white paper. Therefore I make an image of the illuminated paper in manual mode, fixed shutter aperture and speed. The crw-images I open in "Raw Therapee".

Does anyone know how I can compare light-intensities of different images? I tried saving as 16-bit tiff in "Raw therapee" and open in ImageJ, but imageJ doesn't open the 16 bit image properly. Hope that someone can help...

best wishes,


Offline whim

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Re: Analyse light intensity via RAW image?
« Reply #1 on: 27 / January / 2009, 10:05:11 »
Hi !

Don't know if you absolutely need to do this via the RAW's but in case not: have you already checked

Main Menu -> OSD Parameters -> Miscellaneous Values -> Show Scene Luminance (cd/m2)

That will add the luminance value to your OSD (if you have selected to include Misc. in OSD elsewhere)


edit: ... and welcome to the forum !
« Last Edit: 27 / January / 2009, 10:23:49 by whim »

Re: Analyse light intensity via RAW image?
« Reply #2 on: 28 / January / 2009, 09:05:51 »
Hi Wim,

Thanks for your reply. Unfortunately this won't work, because i need to analyse a specific area of the image. So i need to use  image processing software. If I use e.g. jpg instead of raw, the camera already makes some corrections so that I can not compare different light intensities quantitatively anymore.



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