How did the images get to the low pixel resolution that you uploaded? That is where the artifacts happened, I think. The more pixels a camera/image has, the more damage you do by downsampling it to 1600 pixels or less wide with something like nearest neighbor. The sharper it is before you downsample, the more crazy-sharp it can be.
Could be. I use the JPEG export tool that's built into ON1. I was never crazy about it in the past, and they just came out with a new version in either version 2022 or 2022.5 but I'm not crazy about that either. But it could also be my settings. Looking at the settings, the only options for resizing method are bicubic (what I used) and resize AI. There's also a sharpening setting in the export dialog that's set to "screen low", presumably low resolution for screen viewing. I'll try screen high in the future. The other settings are high and low resolution for each of mat and glossy photo paper (total four other settings).













