M57 Ring Nebula

Thank you! And where is this version of M57? I don't see it on the page.

I haven't even posted it on my page yet. You can take a look at it via this link: https://astronomy.ru/forum/MGalleryItem.php?id=18391

It looks like more details could be extracted, for example through deconvolution with BlurXTerminator.

I tried BlurX - it works quite well where there is some detail, but where there is little detail, there's just not much to pull out, so to speak.
Contrary to popular belief, this tool doesn't invent anything out of thin air; it merely shapes what is already present in the original data.