Hi there. Possibly helpful info for you regarding slowness of noise sliders
If I attempt to use the noise sliders on an unadjusted file I get a ~.5 second lag which I can live with. I can make many adjustments and some brushing without significant impact on the noise sliders.
HOWEVER, If I activate the Shadow or Highlight or Clarity sliders by as little as 1 point the noise sliders (luminance and detail) become very slow to respond ~2 seconds.
This is essentially unusable to me as I do all of my noise work at the end.
I also noticed that thread utilisation isnt great when I use the noise sliders, never going higher than about 41% net with only 4 out of 8 cores being used to any degree and two being completely unused.
4.5 GHz 17 2600K on GA-Z68X-UD3H-B3 (tried stock clocks too)
16GB low latency high speed RAM.
SSD & WD Caviar Black.
Catalogue on SSD
5DIII, 1DIV, 5Dc
Also MBPro i5 2.5 Ghz, 8MB.
Hope this helps, unfortunately I can not continue with 4.2 or 4.3 as high ISO is a big part of my work. I will be retreating to 3.6 until this is corrected.
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