Device profile quality - around what level should it typically be when doing things right and using a high-end monitor?

questions about practical use of Neat Image
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Shy
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Joined: Mon Dec 31, 2012 10:43 pm

Device profile quality - around what level should it typically be when doing things right and using a high-end monitor?

Post by Shy »

I've made many attempts to surpass quality level 96% when creating a profile for a Sigma sd Quattro, but it's apparently impossible. Using version 8.5.2.
I consistently get either 96% or 95%, Fine Tuning Completeness 93%, and Very Low frequency value of 0.54, which gives the warning "The noise level seems to be somewhat higher than expected". I've tried with two high-end monitors. No details are present in the image area.
The maximum luminance uniformity I get is 96%. Cr and Cb are always 100%.

I don't have any complaint, I managed to get excellent results after all the filter settings tuning. I'm just wondering if the "extra 4%" could make any significant difference (but I suppose most probably not), and whether this is typical or not.
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NITeam
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Re: Device profile quality - around what level should it typically be when doing things right and using a high-end monit

Post by NITeam »

It is normal I believe. Neat Image may be detecting some traces of compression artifacts that generally look more like details than like noise, which decreases the uniformity. That is no problem for profiling though and there is no need to strive for 100% just for the sake of a higher number. The most important is to make sure you use the right area for profiling. In this case, the area is right and presence of compression artifacts is no problem either. By using this area you in fact tell Neat Image to consider those artifacts (that may look somewhat non-uniform) to be noise as well and so to reduce them.

So the profile generally looks very good and I would not bother with re-doing it or tweaking it any further unless you see any actual issues in the results of noise reduction.

Vlad

Shy
Posts: 5
Joined: Mon Dec 31, 2012 10:43 pm

Re: Device profile quality - around what level should it typically be when doing things right and using a high-end monit

Post by Shy »

I see, thanks.

There's actually no lossy compression, but maybe it's something in Sigma's raw processing that's causing this lack of uniformity. I set all of their lousy processes to minimum - "Sharpness" at "-2.0" which actually equals 0 / disabled, "Detail" at minimum which also disables this process. I've verified that they are actually disabled, not set to some low value.

One thing I can't verify is whether their Chroma and Luminance "Noise Reduction" settings at minimum actually totally disable the noise reduction, or do still apply some minimal noise reduction. It seems like it's actually disabled, but I can't verify.

Who knows. This whole Foveon raw processing is very cryptic and proprietary, especially with the Quattro series, so there may be something else in one of the internal raw decoding processes that's creating some unusual patterns.

Bottom line: I'm very satisfied with the results :) Thanks.

Edit: I posted the profile and preset here.

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