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next PZ lens test report: Carl-Zeiss Vario-Tessar T* 24-70mm f/4 OSS ZA
#45
Quote:No, we are not. Our eye's DR is pretty low. Just when we look around, the brightness gets regulated by closing and opening the aperture. DR of RAW far outperforms our vision's DR. We have pretty contrasty vision. High DR has low contrast.

What you are saying is clashing. HDR is high dynamic range tone mapped into a low dynamic range. That is why it looks unnatural. We can't see a high DR because our vision is contrasty with a low DR. We either perceive a high DR capture as totally bland and not contrasty, or when we adjust the tonal curve, we just see a part of the high DR in a contrasty way and the rest of the DR is lost in perceived white and perceived black.

 

[Image: D8D7184DCEBE40CA83096FFEEF55BE40.jpg]

 

This is an example I made to show what increased DR actually looks like. On the left, a normal contrasty DR quite natural (similar to how our vision "works"), of 8 or so stops. On the right what 14 stops look like. The only two ways to make high DR not bland is to put a steep tonal curve in (doing so limits the DR to 8 or so stops again) or by tonal mapping the high DR into low DR (8 stops again).
 

Wait brightcolors.

(I have a professional interest in human vision)

 

You are right that the DR of the eye is low.

But the DR of the visual system is huge! 

 

What happens is that we scan different parts of the visual field (the eye only getting high rez information about a tiny area at any one time) and the brain does something a bit like tone mapping (except it can't really be thought of mapping high DR into low for various reasons) so that we get an overall impression of detail in the deepest shadows and brightest highlights. And part of the neural magic is that it still seems like the shadows are much darker than the mid tones or highlights.

 

This is the problem with HDR photography: it doesn't always trigger than neural effect, so it is obvious that the shadows in one area are no darker than what ought to be mid tones elsewhere.

 

Nonetheless very high DR capture can be very useful, if edited by had selectively, and can seem quite natural.
  


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next PZ lens test report: Carl-Zeiss Vario-Tessar T* 24-70mm f/4 OSS ZA - by Guest - 04-03-2014, 09:29 AM

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