Alrighty, peeps, it would appear that things are going to hell here, so let me try to clear up some of the confusion a.k.a. notice me jumping on the bandwagon and trying to explain the clustermess that's going on with TheO/Pixiv.
First of all, I'm going to try and explain how I see fan art. In my mind, all fan art is divided in two:
1. Official fan art (I refer to it as doujinshi)
I think of it as artwork done by artist B that represents artist A's ideas (characters, scenes etc.). In this case, the original artist (A) allows the doujin-ka (B) to use their idea to make profit, legally. Artist B claims the work process and their interpretation of artist A's ideas but cannot claim full ownership of them, as they are still the intellectual property of artist A until they officially give up copyrights.
Example, Miwa Shirow isn't the creator of Vocaloid but has done doujinshi of it (examples: 1, 2, 3).
Tl;dr: official" fan art is what I call doujinshi: it is usually made to be sold, which means the doujin-ka (B) makes money off the original artist (A)'s idea, with their permission.
2. Unofficial fan art (fan art per se)
The basis of unofficial fan art is that the fan artist (B) agrees to use the original artist (A)'s idea as long as they don't make money from it or claim it as their own. And while a fan artist can't claim copyrights on their images (since the ideas aren't theirs to begin with), they can claim possession of the work involved in making them; whenever someone reposts/uses fan art without the fan artist's permission, they are breaking this rule. Think of it as artist B being merely a fan of artist A's work and wanting to bring a tribute to it. B is not allowed to profit financially from A's work or use it in any way that would damage A's public image while improving B's. B is not allowed to use A's work without their explicit permission.
Tl;dr: This type of fan art is just a tribute or, if you'd prefer, a pretty picture to look at.
(some parts quoted from my own comment on MikuBerry's post)
Again, these are my interpretations. I'm not a lawyer or law-savvy, so I do not know all the implications of the doujinshi vs. fan art debate, but this is what I've used to guide me all these years since I've discovered that, hey, I can save images to my computer!
Some of my tips:
- Check your sources religiously.
- Don't use images you suspect are fan art.
- If you're unsure of an image, ask people if they know where it's from or who made it.
- Credit your resources to avoid suspicion of plagiarism.
- Don't play innocent and don't claim ignorance. If you didn't know up to this point, you must surely know that DeviantArt and Pixiv, as well as any other fan art site, are off limits for image grabbing and using.
- Don't use stuff from image dumps like e-ShuuShuu, Photobucket, Imageshack etc. without going through the steps mentioned above.
- Never claim images you didn't draw/create yourself. Avoid plagiarism.
- Name your files properly. Try to include the names of the artist and the person who uploaded the image or at least the site you got it from. (when I download scans from Minitokyo, this is the file name I save them under: SERIES NAME scan name [uploaded by UPLOADER NAME])
- If the site is in a foreign language, use Google Translate, Babelfish or another online translator to read the FAQ/TOS.
Some other helpful posts that you should take your time to read:
Oh, and I do believe the Pixiv drama level is about to beat the paysite drama level in the Sims community. Woe. I usually love seeing drama but the case here is too serious to crack jokes, so I guess I'll be watching from the side? And expecting a proper FAQ/TOS section, just like we all are (I hope).
EDIT: replaced Kelsey's link as per her request.