On the forum I see many posts about DeNoise AI not producing expected results. And these can range from inconsistent noise reduction across an image to no apparent noise reduction or even different results using different processing methods such as GPU or CPU/OpenVINO.
As a general rule of thumb I would recommend using manual settings or the AI Clear model if you don’t have access to the original RAW file of the image.
But the optimum way to to remove noise using DeNoise AI is using the DeNoise Model with a RAW file of the image as input. But there are many cases where our workflow does not allow this because, for example, the first step in our process may be using a non-destructive RAW editor such as Lightroom, Capture One, ACD See etc., etc. Or we may prefer the RAW processing in products such as Photoshop (ACR) or Affinity Photo etc.
If your workflow doesn’t allow you to use DeNoise as the first step in processing the RAW files there are some things that will help in getting the best possible noise reduction results consistently. These are:
Do not apply Noise Reduction or Sharpening before exporting the image to process in DeNoise AI. For example, in ACR, Lightroom, Capture One, Affinity Photo turn off the Noise Reduction & Sharpening before developing or exporting the RAW image.
If you are exporting from say Lightroom or Capture One etc., please make sure you choose a lossless format to export. By that I mean a TIF/TIFF, PNG or JPG/JPEG of 100% quality.
To give you an example of the differences here is the same image exported from Capture One and processed in DeNoise AI. The first is a JPG with Noise reduction and Sharpening applied to a file of 50% quality whereas the second is a JPG of 100% quality with Noise Reduction and Sharpening turned off before export. And, as you can see there is a big difference in the result using Auto settings in DeNoise AI (note disregard the Color Noise in the 100% quality image):
JPG exported at 50% quality, with Noise Reduction and Sharpening applied
JPG exported at 100% quality, NO Noise Reduction or Sharpening applied
Note FYI I did not apply manual Chroma noise reduction in this example just to see the difference.