New ACR AI denoise extremely demanding

AI Denoise isn’t new, what’s new is being able to apply it interactively. Previously, you had to generate a copy.

To do it the new way, you have to enable a Technology Preview option. That may be part of why it’s slow: It was put out there for user review, the code is not finished, and so performance optimizations might not be complete. For example, Lens Blur was much slower (painfully so) while it was an Early Access feature; now that it’s a regular feature it is much faster.

The fundamental hardware demands of AI Denoise are not new. It is extremely demanding, and has been since it was introduced a year and a half ago. There are many web pages comparing how fast AI Denoise is on various hardware. The general takeaway is that the number one factor in how fast AI Denoise is, is the speed of your graphics hardware. Your specs don’t mention the GPU at all. You certainly have enough CPU and memory, but for AI Denoise, as long as those are at a good level then the GPU is going to make all the difference. Regardless of CPU or memory, generally a good GPU will get the initial AI Denoise of a 46 megapixel file down to under 15-20 seconds. Older computers may take many minutes. 

If your computer gets the initial AI Denoise down into that time range, it’s probably OK there, and after that, the jerky interaction with the Xencelabs tablet is probably a separate issue related to the Tech Preview code not being fully optimized and maybe competing too much with the tablet driver for CPU cycles (that is a guess on my part, not an Adobe explanation). I have seen a similar problem using a Huion tablet driver a while back under unrelated conditions. I have not seen jerkiness with the Technology Preview on, but I am using a totally different configuration (Wacom tablet driver on a Mac).

Someone else in this forum posted that Camera Raw was generally running slower if this Technology Preview feature was on, so you’re not the only one. These types of problems should be reported in the Bugs section of the Camera Raw forum here so that Adobe sees them and can fix it for the code’s final release, since getting that feedback is part of the point of putting it out as a Technology Preview.

And of course if you need full performance, then you go back to the default, turning off the Technology Preview feature and using AI Denoise the stable way (through the dialog box and making a DNG copy).