Here's a nice -$200 OFF discount on the Rokinon 8mm Cine Fisheye Lens (for Nikon mount while supplies last). There's a few reasons many of you may consider this lens deal. Let's start with the fact that it's one of Rokinon's Cine lens with built in focus and aperture gears to use with your follow focus and a de-clicked aperture ring.
Also don't be turned off that it's available in a Nikon mount, that's actually one of the best options out there if you're trying to adapt this lens. Basically you can easily adapt a Nikon lens to a Canon DSLR but not a Canon EF to a Nikon. Some people prefer to buy the Nikon mount for MFT cameras so that they can use a Speed Booster or Focal Reducer adapter instead of buying a dedicated MFT lens (though you may not need one for this fisheye).
Let's not forget that instead of buying an MFT lens, adapting this Nikon fisheye will let you use adapters like the FotoDiox ND Throttle with a built in Variable ND Filter that sits 'behind' the lens. As you know with a Fisheye lens you can't easily throw a filter on the front which helps to control the shutter speed of your video.
FotoDiox ND Throttle Variable ND Filter Lens Adapter
And yes it's a Fisheye lens, but on a BMPCC or GH4 camera at 4K it's no too much of a fisheye look and can be corrected back down to 1080p for that wide angle view (article here). While supplies last (find it here).
Rokinon 8mm t/3.8 Fisheye Cine VDSLR Lens for Nikon $199.00 (Regular $399) Free Shipping. Good while supplies last!