Let's begin with how fractal art can be compared to photography. Great photography can be set up or staged a certain way to get the effect that the photographer wants or it can be by pure luck that such a fantastic opportunity that events that moved the photographer somehow presented itself. So too with fractal art. The artist can come up with some sort of plan as to how they want their piece to look or they can happen across something completely by surprise. However, with fractal art, we use programs that create certain files called parameters. These tell the program what formula we used, what colors, specific numbers, etc. Parameters would be like a photographer jotting down the exact measurement of how far from the ground his camera was when he took a picture of some grass or how wide his aperture setting was, what lens he used, what film, etc. They are also pretty much like the negatives or undeveloped film. The only difference between the negatives and the parameters is that it appears to me that negatives are copyrightable where as parameters are not. The parameters are just math formulas and as such can not be copyrighted. Kinda lame to me. However, the images those parameters make are copyrightable.
During the past two years, it would seem that is incredibly easy for parameters to fall into the wrong hands. Back in 09 when I was the fractal art GM, people had come to me with something that I found to be incredibly concerning. Someone had sent them a trojan program that they had developed to take their parameters and had disguised as a program that could improve render times. (when you render a fractal piece, the program you are using actually makes the image pixel by pixel.) This gave the parameter thief access to countless amounts of parameters from many artists. This person would have been able to reproduce any image that the artists had created. But nothing could be done for these people unless their exact images or ones that were pretty close were posted. In fact, nothing was done. Now it is happening again, only in a different manner from before. It would seem that the person who had fished out all of the parameters previously had sent out an email with all of them to various different recipients across the spectrum of sites from here to renderosity. Some people have taken these parameters and instead of using them as learning tools, have just deleted a layer here or changed a color there and have posted the altered works. It's rather upsetting.
The cold hard fact of the matter is, Fractal Art is a budding medium and idea. People really don't understand it or at worst, don't consider it important or art. There's only so much we can do as a community to help progress the medium and movement, but there is a lot more we can do as individual artists to help protect our work.
Firstly, do some exploring of the community. Getting to know the artists and the programmers and developers will help you come a long way in knowing who you can trust with your work. Don't download any programs from an unknown source. If it's too good to be true ("This program will help cut down your render times by 50%!") it's most likely a trap.
Second, know your rights. Once that image is rendered, you own it. You made that piece, it's yours to choose what you do with it. if someone posts the same exact image, it doesn't matter how they got it, it's a copy of yours and you made it first. Report the copy. Also, this is where I would like to point out that this is not theft. It's copying.
(Enjoy this brief little video: [link] as pleasant as it is, it will hopefully help address how we handle situations.) I realize that we all feel like something is stolen from us when we see the exact same picture posted that we put our hard work into. However, the only thing that is being taken away from you is your recognition for creating the work. Cool down and approach the situation calmly and much more is likely to be done for you.
Finally, I would just like to say this: Accidents happens, mistakes are made. There is no use crying over spilled milk. All you can do is clean it up the best you can and work harder at not spilling anymore. We need to learn as a community and as individuals that there will always be some kind of negative force trying to undermine us or exploit us. Kick in the balls, tell it to fuck off, and move on. Sometimes it takes a while to learn this lesson, but once it's under your belt, you're set. Hopefully, if you're new to this sort of thing, you can learn from other people's mistakes. If not, as I said, just try to do the best you can with what you've got.