Probably what no one has ever told you is that aRGB is an *editing*
space and sRGB is a *display* space (and also a capture space). Just as
you can with 8 bits easily destroy smooth color gradients when editing
you can also go outside of the color space when editing with sRGB.
Conversion to aRGB was meant to be a temporary editing step. Once
through editing you would convert to an output profile just as you
convert 16 bits to 8 bits for output.
At least so says Bruce Fraser, Chris Murphy and Fred Bunting in Real
World Color Management (second edition) I quote page 278:
------------------------------------------------------------------
Device Independent RGB
One solution, embodied in Adobe Systems' applications but usable by
others, is to use a device-independent, gray-balanced, perceptually
uniform space such as Adobe RGB (1998) for editing. This approach has
proven sufficiently popular to spawn a plethora of editing spaces -
often named for their developers - and debating the merits of each is
decidedly outside the scope of this book. Instead, we'll simply say
that the main criterion in choosing an editing space is its gamut.
Bigger isn't necessarily better. The trade-off is between finding an
editing space that won't clip colors in either your capture or your
output, and finding an editing space that doesn't waste huge numbers of
bits describing colors that you can't capture, display, print or, in
some cases, even see. In practice, it's pretty much impossible to find
a space that contains all your colors yet doesn't waste bits, so you
simply have to pick the best trade-off for your particular purposes.
-------------------------------------------------------------------
Chuck Norcutt
Fernando Gonzalez Gentile wrote:
> If you're serious on this (I assume you are), then I must start
> thinking this whole thing over.
>
> I'm not suggesting it's a bad thing, I'm stating it's horrid.
>
> If I buy a pair of loudspeakers, I choose one which would represent
> input as accurately as where the musicians played.
>
> I avoid 'colored' or 'voiced' loudspeakers. I avoid 'laid back' or
> 'forward sounding' loudspeakers. Wide dispersion high-frequencies v.
> narrowly focused.
>
> Hope this comparison can be understood.
>
> sRGB ... nah!.
>
> Fortunately, I will never see the difference, as my monitor isn't up
> to show it to me.
>
> After I edit anything in aRGB, and then convert to sRGB, PS doesn't
> show differences to my eyes, no matter how many carrots I had eat
> during the former week. But the histogram may show some differences.
>
> Fernando.
>
> --- still learning.
>
> 2009/12/10 Ken Norton <ken@xxxxxxxxxxx>:
>>> Does it imply that we are _always_ dealing with a finite number of bits?
>>>
>> Yes.
>>
>> But I'm not suggesting that it's a bad thing. Each colorspace has distinct
>> advantages over another. One colorspace will represent the middle-tones with
>> more bits at the expense of the high/low tones.
>>
>> _____ Schnozz
>> --
--
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