Great lens for certain needs.
Got this lens for the extreme wide angle. It does what I need it to do. If on 10mm it almost surrounds you in wide angle, but distorted as fisheyes do. At 17mm inside there is still some distortion, so be aware of this. Landscape shots at 17mm wouldn't show this as much. I got it for fun more than anything else. Build is very good, nice weight, and very solid, Small lens as many Pentax lenses seem smaller than their counter parts in Tamron, or Sigma for instance. The only draw back is that there are no filter threads so you will need to figure out something else if you need filters, but it can be done. Cokin filters can be handheld, but in 10mm it's hard not to catch your fingers. The little permanent hood protects the lens and may help somewhat in cutting flare, but a bigger hood would get in the picture, so you accept it, or rig something, I don't know what. Value?? I bought a Rokinon 8mm manual. I like that too, but mine is rectangular, where this is circular. Both are fun. The Pentax is twice the money, but you get a more consumer friendly lens, both seem well Glad I got it, that's about all I can say, except the pictures are acceptably to very sharp. The lens cap is a friction type, with a liner to hold it in place. I have had caps like this before without troubles, this is snug, may loosen with use, only time will tell that.
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