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1Dx ISO100 high DR shadows SNR improvement

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Resizing down to 8Mpx file dimensions?  ;D


--- Quote from: nightbreath on November 04, 2012, 02:19:17 PM ---Resizing down to 8Mpx file dimensions?  ;D

--- End quote ---

No, full sensor resolution )))

OK, no magic - just "feeling" what is behind numbers )))

But seriously  this method used for decades for filtering noise out in different applications.
This is use of simple math in real life use.
Noise is random - image is fixed.
So what is required is just to integrate information element for a longer time and random noise would be filtered out.
  I believe that  this is something that  also was being used in astronomy to separate low level image details that could be even below random noise level.  Also used in communication systems.
So how this is done with 1Dx ???
1Dx has one feature which is  intended for some artistic work but it could be used for something completely different.
This feature is multi-exposure – in one of the posts I mentioned about this for filtering out noise.
You can take up to 9 shots and 1Dx will average these shots into one.
 As each shot has it's own random noise distribution then averaging 9 shots into one would  essentially suppress noise - only fixed elements will  be kept - so random electronic noise is significantly reduced but fixed patterns - real image or sensor defects are kept and cleared out of noise. This is equivalent  to 9 times of longer integration time of the information element in the image detector.

How to  do this in 1Dx:
Enable  multi-exposure continuous shooting, number of exposures to 9, multi-exposure control to  Average (to integrate over 9 images) , put mirror lock up with the set button release  to reduce camera vibration (will be returned back by set button) , put camera in high speed continuous shooting mode, press shutter - mirror will be locked, press shutter again and keep it pressed - camera will take quickly 9 images in less than 1 sec , stops and then merge it ( integrate)  into one image.
And you are done.
Now press set button to return mirror back and then you could see the result.
So nothing special - just to see things a bit deeper)))
Method is suitable for only still images .
In normal conditions such kind of shot will take about 0.75 sec with FPS =12
And of course could be only shot using strong stable tripod for camera.

Could you do one thing just to test another approach? Please export the RAW file to TIFF and push the shadows in the resulted file. I saw very good results someone shared here using this method.

Thought that might be the 'trick'. I use it all the time in photomicroscopy.  Works great for test charts and fixed tissue.  Not so well with anything that moves, which limits its utility for >95% of what I shoot...


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