I use the AF 10.5mm f2.8 DX Fisheye in a circumcised version, which gives me a 220 degree view. Its almost a circular fisheye on full frame. Thus I dont get how a 8mm lens would possibly look this way as it does in this thread. It should be a perfectly circular fisheye on full frame. Thus I dont think this 8mm was actually used on full frame.
As a general rule of thumb, when I try to check out a lens in a flickr group or something, I look for critical subjects, such as:
- complex natural items, such as human skin, or wood, especially the bark, etc
- flowers, to check for strong colors
- black and white photographs; if a lens does great in this regard, its probably a great lens overall
Images from the night sky however tell me ZIP, or almost zip. Its mostly black with single dots of whats mostly white. Not much to see there, except specific lens errors such as Coma.
I also ideally want the camera run at base ISO, shot from a tripod, and the lens wide open.