Quote - i define pornography as involving sexual acts. pornography can be artistic, but this is generally an afterthought and not the primary purpose.

Now that's way too broad.

If "involving sexual acts" is defined as pornography than you've just lumped in the majority of modern film and television, most novels, and the Bible.  All of which contain suggested or explicit "sexual acts".

Pornography isn't involving sexual acts, it's meant to cause a sexual action (sexual release through masturbation, or some form of excitement related to sex).  That's why porn is largely in the eyes of the beholder.

Meanwhile you have sexual acts that are portrayed for many other reasons, including those involving an erect penis.  The glowing condom "dueling penis" scene from the Blake Edwards film "Skin Deep" is utterly hysterical and clearly meant as comedy, not as pornography.

For the uninitiated, John Ritter is having sex with a woman in a completely dark room, but he's wearing a luminous condom.  You see it appear and disappear a few times with appropriate sounds...and then the door opens and in walks the woman's significant other, unaware that she was cheating on him.  And he's ready for action, hot to trot, ready and willing, pick your phrase.  And he's wearing a glowing condom as well.  And sees (because of the glowing condom Ritter is wearing) that he's being cheated on.  What follows is a physical scuffle the viewer hears but only sees throught the movement of these two glowing condoms like some demented lightsaber battle before Ritter flees the room and the ticked-off guy.

Let's see, there's the rape seen in "A Clockwork Orange".  Meant not for sexual titillation but to express how demented Roddy MacDowell's character was and provide justification for the revenge carried out on him later by the couple.

"American Beauty", where everyone is cheating with everyone else and the repercussions thereof.

And so on and so forth.

Now, when it comes to the galleries here there's not an issue with certain guidelines being set about what is allowable or not through some criteria.  But don't pretend that means you've clearly defined pornography because there are plenty of images, some with people not nude at all, that could be used to the same ends.