Opteka 3.2 Telephoto lens on a G5.....?

I got a camera kit for Christmas and it included an Opteka 3.2x High Definition² Professional Telephoto Lens. I have a G5 and when I have this lens installed, I get black areas around the edge of my pics.....vignetting I suppose. Also their is some distortion around the edges.

Is this normal?

Anyway to help the problem?

Camera Kit
http://cgi.ebay.com …ame=STRK%3AMEWN​%3AIT&rd=1

i dont know if its relavent, but i have dslr and i found a good deal on a opteka 500mm lens with a 2x multiplyer, so i got it, ya its the worst think i have got yet, i would be better off shooting at 300mm and blowing up the image than shooting at 1000mm with that lens. like i said i dont know if its at all the same, but my experance with their product was not good at all

are you zooming all the way to maximum zoom when you are using it? if not, you might get vignetting, like you describe. Opteka isn't known for it's quality, but experiments are fun!

Yeah, zoomed all the way and still get the vignetting. I guess ya get what you pay for??