Best fisheye lens for a Nikon D3100 (DSLR Camera)?

I want to get a fisheye to film with on my DSLR. I've been looking into a Rokinon 8mm and an Opteka 6.5mm. I'm not trying to sound cheap, but i'm not in a good financial position to pay alot of money for a Sigma. So if there's any other fisheye lens I can put on my DSLR, that are 250 or less, Id appreciate it if you told me about it.
-Thanks

The 6.5 mm lens will give you better coverage.

But when a Nikkor and Sigma costs nearly $1, 000, the Rokinon or Opteka are about as low a price as you will find

Just save your pennies just wait until you can budget for one of them. Unless there's an assignment that requires you to use a fisheye, you will have to wait

Well, try the Bower 8mm f3.5 it's priced the same with the Rokinon around $289 which fits your budget. I don't think you will be able to find a brand new lens for the price of $250

Just remember; a cheap lens produces a cheap result. In my view, you are wasting a hundred bucks on one of those lenses which will give you marginal results. It would be better to save that $100 for the future purchase of a decent lens.

There's an 8mm f3.5 fish being sold under various names which is as cheap as you can get and still get acceptable quality. Be aware that it will function in M mode only.another option is tokina10-17 which can sometimesbe found used for less thqn 500. The best lens would be Nikon and they are expensive.

I think going with Opteka 6.5mm is a nice choice. The Opteka 6.5mm Manual Fisheye lens may be the best master of disguise I have ever found. It is actually produced by Samyang, who market it as an 8mm lens, Bower, Falcon Polar, Rokinon and Walimex also have their name stamped on some of them coming out of the Samyang assembly line. Despite all of this confusion, I can see why everyone wants to claim this lens, Its AWESOME!