Thanks. Understanding that it's a non-linear process make a lot of
things much clearer. But I never venture away from sRGB.
Chuck Norcutt
Ken Norton wrote:
>> Then colorspace interpretation/translation is a non-linear process?
>>
>
>
> Absolutely. That's the entire purpose behind a colorspace. In an 8-bit per
> color (24-bit) file, each color has a maximum of 256 values. As Moose so
> accurately pointed out, as a general rule in the A-D process, the top stop
> worth of light values take up half of the potential bits. This doesn't bode
> well for editing of anything in the other stops. Therefore, what happens is
> we rob bits from the top stop and spread them out for the rest of the stops.
>
> How the bits are spread out is the magic. The aRGB colorspace assigns a
> different number of bits to each stop as sRGB does.
>
> Again, this is different than the original RAW file, which really has a
> non-usable "colorspace" as it is essentially just voltage measurements. It's
> meaningless to edit a RAW file as there is no standard there at all and each
> and every camera stores the data with different meanings. Inotherwords, a
> green channel measurement of 647 might be one color/brightness in one
> camera, but the exact same color/brightness in another might be 989.
>
> aRGB and sRGB are "working" colorspaces. sRGB does have the added benefit of
> being the colorspace used by most electronic displays, though. Whenever a
> printed output is involved, there is a conversion of the working colorspace
> into the colorspace used by the output device itself.
>
> If your output colorspace is sRGB and you have little serious color/contrast
> adjustments to make, it is always best to work in sRGB and avoid
> conversions. There are a few exceptions to this rule, but...
>
> AG
--
_________________________________________________________________
Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
Archives: http://lists.thomasclausen.net/mailman/private/olympus/
Themed Olympus Photo Exhibition: http://www.tope.nl/
|