I tried revisiting one of my iconic (to me) photos using DxO PhotoLab 3. Their PRIME noise reduction engine is rather impressive. I know LR hasn't been well regarded in the NR department for a while, but I think this is an interesting comparison nevertheless.
The shot was taken 10 minutes after sunset. I had my 18-135 lens on (unusual for the circumstances), the aperture open to f/4.5, had pushed the K-5's ISO up to 4,000, and still the shutter was marginal at 1/160. In other words, there wasn't a whole lotta light and as I couldn't afford a slow shutter I had to push the other sides of the exposure triangle.
Anyway, here's the result I originally published, which was processed in Lightroom. I remember pushing the noise reduction slider too far and then pulling it back to get this. I told myself the noise in the sky added character.
You can see the full sized (3200px) version on the Flickr page.
Here's what I was able to do (without a lot of effort) in DxO. I reprocessed the photo with no reference to my original effort (until it came to cropping for this comparison). I just went with what felt right this time around, including using DxO's Smart Lighting and PRIME noise reduction. I'm not sure how to (or even if you can) view full sized attached images here, so I have also included a 100% cropped sample area of each side by side (I didn't perfectly match the crop of the full shot).