Trouble with color noise in RAW scans, image noise disappears when hiding the Lightroom detail module

Image Editing Help
1

Hi all, I’m having a lot of trouble with color noise when editing my negative scans with Lightroom v13.0.2 and was hoping someone might know something I don’t that could help me fix this.

I am using NLP v2.4.2, and scanning with a Nikon Coolscan V using Vuescan 9. I scan all negatives as 48-bit raw files and don’t touch them further in Vuescan. After scanning, I take my raw files and import them into lightroom, update the metadata for a Silverfast/Vuescan raw file, and then convert the images one by one with NLP.

Here is where the issue begins. Conversion with NLP is completely successful. I usually leave sharpening in NLP’s window to “off” (please correct me if I should not be doing this). However, the inverted negative is often filled with color noise. Historically, I have used the manual noise reduction in Lightroom’s “Detail” panel, which has the unfortunate side effect of removing a lot of sharpness and detail.

However today I discovered something odd: if I toggle off the Detail panel with the small eye icon, all the noise disappears completely and I am left only with the natural grain of the negative. See this gif for exactly what I am talking about: link to gif (too large to paste inline)

I’m not sure what is causing this nor how to fix it. As far as I know the little eye toggle is temporary and there is no way to make it stay “off” all the time.

Has anyone had a similar issue, or does anyone have any guesses as to how I might fix it? Now, seeing my photos with the noise toggled off, I’m keen to get rid of it in all of them as I can now see how big of an impact it has.

Thanks very much in advance for any help or insight you all may be able to provide. I greatly appreciate it.

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Welcome to the forum, @specialx

Wild guess:
Switching off the details tools will make Lightroom display image(s) with its default settings.

In your case, this means that “no noise reduction” is replaced by “default noise reduction” which is set to balance noise reduction vs. details. Do you get the same effect if you set detail sliders to their default values?

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Thank you for the welcome!

Your guess was absolutely spot on. I reset all the sliders to their default values by double clicking on them, and lo and behold not only did the image now look identical to the image “without noise” that I shared in the gif above, the eye actually disabled itself, so I no longer have a choice to “disable” the details panel. Thank you for demystifying this! I would never have guessed that the eye sets the panel to its default.

My question now is, why is there so much colour noise in the first place? If I am using a scanner, which to me is a controlled environment (which I may be misunderstanding, forgive me if I am), can’t it just increase its exposure time or lower the sensitivity of the CCD to reduce noise?

Thank you again!

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The eye does not set anything, it simply tells Lightroom to not apply what is set in the panel.

Can’t say, there are simply too many possibilities to add and amplify noise. You could do a few scans and combine them in Photoshop like so. If the image gets better, then it is noise indeed, if not, it’s part of the image.