Warp wrote:
> Alain <ele### [at] netscapenet> wrote:
> 
>>Think of 48bpp png as "extended dynamic range".
> 
> 
>   I thought that the "dynamic" part referred to the fact that the
> format uses floating point numbers (which can scale dynamically to
> bigger ranges by changing the exponent part of the number). PNG only
> uses integers which are mapped linearly, so there's no dynamicity
> there.
> 
I think precisely that what Alain meant was that while 48bpp offers a 
greater dynamic range than 24bpp (namely 511:1 instead of 255:1), it is 
far from being truely "high dynamic range" (the dynamic is 10e38:10e-38 
for .hdr, 65000:0.0000012 for .exr)...

-- 
Vincent

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