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Old 16th November 2015
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PeterBirder PeterBirder is offline
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Re: Expose to the Right of the Histogram!

Quote:
Originally Posted by Ricoh View Post
I have not heard of this before but it sounds like some form of an algorithmic guessing game, since once the well is full, there's no way for the electronics to determine the degree of clipping. 1x, 1.1x ...10x, or any other value. Some form of interpolation based on neighbouring pixels, maybe.
If someone knows better, please pipe up, I'm more than intrigued.
You are assuming that clipping occurs at the sensor photo sites.This would only be the case with a monochrome sensor.

Our cameras have sensors with a Bayer Filter in front of them to give colour. Individual photo sites see only Red, Green or Blue and there are twice as many Green photosites as Red or Blue to mimic the physiology of the human eye. The Green photosites are used to produce the Luminance channel in the image pixel as well as contributing to the colour of each pixel. To generate an image pixel interpolation between the data (after analogue to digital conversion) from surrounding photosites is used (in raw convesion) to produce the colour for each pixel. Since there is twice as much data available for the luminance channel (and this is at up to 16 bits deep) there is some latitude to recover highlights in raw conversion. As John indicates this will not work with grossly overexposed images. This is one of the reasons that "shooting raw" can be beneficial.

For more detailed information see : https://en.wikipedia.org/wiki/Raw_image_format

And :https://en.wikipedia.org/wiki/Bayer_filter

Regards.
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