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Thanks for the comments. I am just starting to get to grips with this HDR. It is actually capable of working with images with 96 bit depth.There is no way of displaying this dynamic range. This is then converted to an image of 8 or 16 bits using human visual perception algorithms which is logarithmic to show the full gamut of detail in the 96 bit image in the low dynamic range of 8 or 16 bits.
If you consider the Canon 5D has a 12 bit A to D converter and its actual dynamic range (signal to noise ) is 14.3 stops. Then producing an image from four exposures differing by one stop each (x2 exposure) you can potentially produce an image of 18+ stops dynamic range.
This is why the stars all have colour and the nebulae are not blown out in the bright regions but still show detail in the faint regions. This also explains why the dark regions are also almost noise free. There is actually more detail in the dark regions but it is starting to get noisy. More even longer exposures would minimise this noise. One could collect data all night!
I will keep exploring this method. Just bear with me if the colours get to much! This technique will show details and colour not possible with conventional methods. It would be interesting to see what could be done with a 16 bit chip such as the cooled B&W Astro CCD's.
This would also work for planetary images if the dynamic range of intensities of the planet was higher than the detector. One shot colour would be better
B&W would be a nightmare with the planet rotating.
One thing I would like to try it on is a crescent Moon to show in the one image the bright Sunlit crescent and the Earthlit part.
Bert
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