In this case meaning painting, drawing, etching.
Quite rare case in my own habits actually. Something like Nicole 12 "Black Line", there was actually hired mr. Jukka Siikala to paint the cover according to my instructions. Besides that, when thinking art that would be done by lets say actual artists, not just original art by myself or some sound maker who can put together something neat... but kind of legitimate artists who does their work on visual arts.
I was thinking this when watching Merzbow "Psychorazer" original edition, with cover by Suehiro Maruo. You could list easy examples like Trevor Brown doing Whitehouse covers.
Of course reality is that many noise artists can do visual arts. I like something such as Prurient "The Baron's Chamber" CD graphics, that is just there weird rather primitive drawings of Fernow himself, as opposed to just picking up selection of found photos into collages.
Not saying the usage of found good photos is necessary bad. This is vast majority of my own work. Recontextualizing old photos, manipulating them a bit. Still it makes me wonder how little there seems to be drawings, paintings, and other hand made visual arts in power electronics and harder noise. Of course depending what is the "harder side". As example, you could check Tone Filth / Devillock or a lot more playful Ultra Eczema with Dennis Tyfus doing his goofy colorful stuff. Of course you always do not know what would be "original art" made for album, and what are something pulled out elsewhere. Like let's say Sleep Chamber tapes with great drawings. A lot of them are classics you will see elsewhere is investigating erotic art. Some may feel drawings may not be enough dark or brutal for specific things, but even somewhat comical works of Miguel Ángel Martín would be used by Whitehouse, Hydra and Maurizio Bianchi.
As much as I like good photo that makes impact, or neat collages or such thing.. It feel at the moment that perhaps it would display somewhat more darker and obsessed spirit, if instead of pulling out photo from magazine, also people who can't necessary paint or draw, feel necessity to do so to express themselves. Where clumsiness and the weird is not negative element. I can imagine what it could be if the stuff like Nate Young's Wolf Eyes style graphics would be depicting.... hmm.. darker topics! Of course, that is just my personal preference. Many could say that Nate's work is amazing as it is. Which is fair assessment!
Own experiences of using, asking, trying to get "original art" from illustrators?
Favorities of such covers?