Thought this may be of interest . As I broke my Samyang 14mm although I taped it back together I wondered if I put my Sigma 10mm on the 6D with the Kenko 1.4 extender how it would go. So I now have a 14mm f4 fisheye. Here are some pics 30s ISO 6400 with a little light painting of my favourite tree. The last pic with the tunnel is uncropped and shows the vignetting at the extremities. Also in the first pics note the Zodiac light to the right which had dissappeared by the time I got to the tunnel.
that's unfortunate about the 14mm.
Lovely Zodiac light captured
I need to find myself a tree like that. The only ones i have found are on the other side of the fence.
Might have to go out in my worst pair of pants next time just in case