Subtlety Moose writes:
<<<I don't know if it's sensor limitations, lens (probably not) or imperfect
X-Trans sensor demosaicing, but there's a point in the finest feathery parts
where details just sort of mush away.
I agree with the Moose conjecture that much of the fault is the demosaicing
algorithm.
I know I harped on this before.
CFA's have trade offs by nature. Xtrans colored filter array is designed so
the "green" raw
channel has more coverage but less positional symmetry than in a Bayer sensor
and as a direct result there is less high-frequency luminance
"miscalculations" in the interpolation, giving lower noise in raw conversion.
The larger B to B and R to R distances necessitate a large chroma smoothing
radius resulting in "watercolor" effects or artifacts- some converters seem
to smudge detail in the process as well -balance
seems different with different converters. The ACR in PS and LR used to be
plain lousy with RAF files, but improved , if suboptimal now. Accuraw allows
one to adjust the balance of artifacts and more resolution vs watercolor
effects--though have never used it.
http://www.dmcgaughey.com/2012/12/31/fuji-x-trans-raw-conversion-accuraw-takes-a-swing/
Please see some of these early comparisons.
Is a more perfect solution theoretical possible? --- Probably yes. Someone
with less rusty math might suggest a POCS algorithm or using a more advanced
multi-pass interpolation algorithm with best fit iteration for a layout that is
inherently asymmetric.
The penalty is the very resource intensive nature of these techniques and not
sure if people would want to wait several minutes for one conversion. It
appears C1 and Iridient remain superior though I have not looked in awhile.
Also , one person's artifact may be another's "organic rendering." Does any
of this matter?--ALWAYS to pixel peepers but perhaps not a whole lot anymore
for web images or prints.
Mike
--
_________________________________________________________________
Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
Archives: http://lists.thomasclausen.net/mailman/private/olympus/
Themed Olympus Photo Exhibition: http://www.tope.nl/
|