Luminance noise reduction in C1: increasing contrast?
The "Luminance" noise reduction slider is by default at 50, even for low ISO files. I noticed that, if I set it to 0, expecting the image to appear more sharpened, the image ended up less sharpened - or rather, upon further inspection, less contrasty (less local contrast).
Does C1 increase local contrast "under the hood" when the luminosity noise suppression is increased?
Anyway, I find that with luminosity noise reduction at 0 instead of 50, and the default sharpening settings, images look more natural: with luminosity noise reduction at 50, they are often exhibit too much local contrast to my taste.
Does anyone see the same thing (I use a D700)?
Does C1 increase local contrast "under the hood" when the luminosity noise suppression is increased?
Anyway, I find that with luminosity noise reduction at 0 instead of 50, and the default sharpening settings, images look more natural: with luminosity noise reduction at 50, they are often exhibit too much local contrast to my taste.
Does anyone see the same thing (I use a D700)?
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In this case, if you push the settings to 80 (for example) the contrast is still up, this is not the case with me anyway.
If the contrast with the rising noise reduction, histogram would be affected, this is not the case. 😕0 -
Well, it's true that the histogram doesn't appear to change.
But I do see a difference in the picture... The contrast, or local contrast, increases most when one goes from luminance reduction 0 to 50, then there is little if any difference.
I could post an example if I knew how...0 -
[quote="bernardf" wrote:
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I could post an example if I knew how...
Bernard,
You can post a link to an image file here. Post the image file on your own or one of the many 3rd party file services (like Dropbox) or image websites (like tinypic.com).0 -
Thanks Paul.
So here it is: this image has Luminance noise reduction at 0.
<a href="http://tinypic.com?ref=2dmb19l" target="_blank"><img src="http://i61.tinypic.com/2dmb19l.jpg" border="0" alt="Image and video hosting by TinyPic"></a>
This second image has Luminance noise reduction at 50 (default value) - and it shows more contrast (or local contrast?).
<a href="http://tinypic.com?ref=dc8mt3" target="_blank"><img src="http://i57.tinypic.com/dc8mt3.jpg" border="0" alt="Image and video hosting by TinyPic"></a>
Not very visible on screen, but if you download the pics and switch from one to the other, it's obvious.
An interpretation I was given is that removing L noise is most visible in the shadows -- and since noise grays up shadows, removing it will darken them. This in turn could lead to your impression of less contrast since with noise present, the blacks are possibly not as deep.
Actually we are at ISO 200 in this pic, from a D700, not much luminance noise to be seen. But the algorithm is still operative I guess. It is less easy to see the effect at ISO 1600 for instance, because then the noise is visible, and removing it makes the contours less clear cut, thus diminishing the apparent contrast.
Anyway... I found this effect interesting because i often feel that the default rendering of C1 is too "sketchy", as if the edges were underlined. Decreasing the luminance noise reduction to 0 (when possible) reduces or eliminates this effect.0 -
I can see the difference - not huge, but it's there.
Could you try running the non Capture One NRd version through some other NR, to see whether it's "just" an NR thing, or a Capture One NR thing?
Just a small point to add to the discussion: Capture One applies some Luma NR even when the slider is set to zero.0 -
Hi Bernard, I repost a part of your message as the images did not show up in my browser. Hope this helps.
I see the difference as you described. Interesting observation.[quote="bernardf" wrote:
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So here it is: this image has Luminance noise reduction at 0.
http://i61.tinypic.com/2dmb19l.jpg
This second image has Luminance noise reduction at 50 (default value) - and it shows more contrast (or local contrast?).
http://i57.tinypic.com/dc8mt3.jpg
Not very visible on screen, but if you download the pics and switch from one to the other, it's obvious.0 -
Thanks Paul. 0 -
[quote="Keith Reeder" wrote:
Could you try running the non Capture One NRd version through some other NR, to see whether it's "just" an NR thing, or a Capture One NR thing?
I tried running the Capture One "luminance noise reduction=0" version through Lightroom 5 with luminance noise reduction, or through PS with Nik Define or Topaz DeNoise. And in fact, in all cases, the contrast was reduced when luminosity noise reduction was applied.
Thus, perhaps the interpretation that removing L noise removes grays and thus deepens shadows is perhaps not the right one. Perhaps in fact C1 does increase contrast as a way of counterbalancing the loss of contrast due to noise reduction?
Could someone from Phase One give some clue as to what is happening there?0 -
No comment from someone from Phase One? 0 -
I return on what I said, I did not succeed has to download your images I thus resumed an image in mind of the one that I have just seen.
And indeed I noticed the same thing(matter) as you!
https://dl.dropbox.com/s/45gzq6tgi2id5fi/Capture%20d%E2%80%99%C3%A9cran%202014-08-24%20%C3%A0%2018.07.09.png?dl=0
On the left image the regulation is has 50 luminance and colour, has luminance left-handler(left) 0.
Different histogram and different colour data.
Désolé pour mon Anglais 😕0 -
[quote="bernardf" wrote:
No comment from someone from Phase One?
This is a "user to user" forum that occasionally gets a response from P1 personal....
Perhaps you would get further in your quest for knowledge by asking via a support case? 😉0 -
I tjought the discussion would benefit the community, not only me...
But I will try a support case.0 -
[quote="bernardf" wrote:
I thought the discussion would benefit the community, not only me...
I imagine that for most of us it's just a little quirk that warrants brief acknowledgement but no more, Bernard - it's not a "problem".0 -
[quote="bernardf" wrote:
I tjought the discussion would benefit the community, not only me...
But I will try a support case.
Yes it does to some extent offer something interesting to the community discussion although may not be of great importance to many - just interesting.
However you seemed to be asking for a Phase representative to respond. They may but it's not guaranteed that anyone will feel able to do so. Creating a Support Case should be a better way to obtain the response you seek.
Out of interest I played with a few randomly selected images from my files.
Some showed hardly any effect at all - especially at 100%. Others showed more significant colour and luminosity value variations in some of the spot samplers but not as great the changes you saw and visually it was very difficult to see any real difference.
I suspect that the effect may be more evident in some areas of colour than others. In fact "greys", given how they are constructed in a colour array, may be more susceptible to numeric value changes in the pins than areas of single colour. At least that is my theory. I'll see if I can build a collection of samples to support it!
Grant0 -
I have created a support case. I'll keep you informed... 0
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