Seriously wrong blotting

I was using VEAI, Proteus 3, and got some very severe blotting in my Solaris movie I’m trying to upscale. At first I thought I had denoised too much, but even at default, minimal denoising, I get these very erroneous blots all over the place:

Those continue throughout the movie, making the process utterly useless.

N.B. This is curious: the bug does NOT occur with Proteus 2. (Sic!)

I got the matter escalated to a developer, via support, who acknowledged the issue, and has put it on the list for investigation/resolution.

During the feedback I gave support, I noticed this bug only occurs when scaling beyond 200% (with Proteus v3). Like the 270% I used to get a panned view, to get rid of black borders.

I was able to bypass this issue by preprocessing with an avisynth script command, like:

Crop (248, 140, -248, -140)

An exact pre-crop, so a 200% scale will yield a perfect 4K.

Support also said “In the meantime, please use v2, you should not find any advantage to using v3.” So, v2 it is then, for now. Even though I may keep using the avisynth pre-cropping, as it will likely go faster (less raw material to process for VEAI).

This blotting artifact only seems to happen with 4k video which I believe is almost always broken with this program, it just leaves those ugly black spots.