Originally posted by reivax Can someone explain how to tell how "fish-eye" a lens is? I'm hoping to get one soon (next 6 months) and want to know what to save for. I took a look at the DA 10-17 zoom and noticed that Field of View is 180-100. Is that what I'm supposed to be looking for? Or is there something else to check for? Thanks.
from what is listed here, nothing at all.
what would be interesting, but I am not sure each software maker is consistent in the use of controls, is the barrel distortion correction required to "defish" a fisheye.
that would tell you something.
as for the question of FOV, 180 degrees is corner to corner at 10 mm, and 100 degrees is corner to corner at 17 mm, both on APS-C sensors.
if you compare, for example, a sigma 10-20 mm rectalinear zoom, the FOV at 10 mm is 109 degrees.
what you can see from this is that the 10-17 has almost the same FOV at 17 mm as a rectalinear lens at 10mm. so even at 17 mm this lens would be quite "fishy"
maybe, without a distortion indication, taking a comparison of the fisheye FOV compared to a rectalinear lens is the best way to judge the amount of distortion.