Noise Reduction seems not to export at the same "rate" as in Develop
I have been working on some photos tonight and had been pretty unhappy with them whenever I exported. I eventually discovered that this is because the exported photos are noisier. This is true even when exporting in lossless formats at 300 ppi, and even when opening up in Photoshop.
I eventually realized that the luminance noise reduction did not appear to be applying to my exports - or at least not applying in the same way it did in the develop panel. I have spent a few hours viewing at 1:1 as well as other zoom levels as well as lining up my exported file to be the same size and in the same location on the screen as the LrC Develop version of the image and then using the taskbar to seemlessy swap back and forth and there has been a very noticable difference.
I also discovered that the library view does not appear to apply any noise reduction at all. I am not using Smart Preview. I have found quite a few older posts both here and on other online discussion pages reporting a similar problem, though some of these go back nearly 10 years to extremely different software versions.
Eventually I discovered that if I pump up the noise reduction level considerably before exporting, I can get the same image quality as I see in the develop panel. For example, see the following two images. The first was exported with a luminance noise reduction of 70, but this image (assuming the way it looks carries over throughthe upload to this site) is what I see when I look at the Develop page in Lightroom Classic with the level set to 30. The second image was exported with that luminance noise reduction of 30, but as you can see (assuming the upload doesn't compress it too badly) it is much noisier than the first.
To make sure I am very clear on this: yes, of course an image with NR of 70 will look smoother than one with a NR of 30, but my point is that the NR 70 export looks like the NR 30 Develop panel image, while the NR 30 export looks much noisier than that, more like an image with a lower level of NR.
Is this still considered a known problem? Is there some way to fix this or to workaround it other than to pump the NR level up extremely high before exporting?

