Well... I wouldn't go so far as to call yourself an idiot.
Life's complicated, there's too many numbers and acronyms to keep straight, and conversational shorthand is often good enough for functioning, so...
May all your errors be so slight!
Okey doke, yeah, homework indicates that camera has a 62mm filter mount.
Digital Concepts is a Chinese lens manufatured by Sakar.
They may have discontinued in 62mm mount 2x tele products and you have an older product or I'm looking at their product pages in the wrong places and don't see any tele's up to 62mm.
http://sakar.com/thumbnails.aspx?categoryid=142
On ebay I see there's this product:
http://cgi.ebay.com/Digital-Concept...17566340?pt=Camera_Lenses&hash=item2c5bbb5b84
But frankly, that description of features is rather lacking in details - like if it's a 62mm mount or if it has a stepdown ring or whatever. "(Includes Rings)" doesn't tell me sh!t.
I've seen all sorts of "marketing work arounds".
You have two issues: blurriness and vignetting.
The bad news is that if you do a google video search for Digital Concepts or Sakar lenses you'll find that blurriness you're seeing is common, especially at full zoom.
There's not a [expletive] thing in the world you can do about that.
If I had to take a wild guess, I'll guess you have a step-down ring adapter, the product is just made by idiots, or there's some sort of tube that's putting the lens elements too far out in front to escape vignetting like looking through a toilet paper tube.
Short sweet: return the product ASAP.
What you're experiencing is the first product issue I posed to this forum not so long ago.
http://www.indietalk.com/showthread.php?t=29818
Like Wheatgrinder says, Raynox makes some nice products and you're gonna get what you pay for.
http://raynox.co.jp/english/video/hdrfx7/index.htm
There's a big ol' list of tele's for your camera.
Wheatgrinder has (a lot) more experience than I do about lenses, but look for something that AT LEAST has a 62mm mount with larger filter lens - or - something that requires a step-up ring to a larger mount and hopefully that will diminish any vignetting potential.
GL & GB
Ray