Anyone else having issues with this lens at f/8 or so?
My copy of the lens has a weird issue. It looks great at f/1.8 until at least f/4. Around f/5.6, the center starts falling apart, getting soft and low contrast. It's very obvious at f/8. I see this for both near objects like my cubical wall at 2 ft as well as for infinity scenes. Outside this soft center area, it sharpens up again toward the edges. A donut of sharpness.
I first noticed in some landscape photos which I focused at f/1.8-f/2.8 and then stopped down to f/8. Checking focus after, the center seemed quite soft. I assumed it was due to focus shift and started focusing at f/8, but noticed that the poor performance at f/8 when reviewing images later.
This one is going back. I'm wondering if anyone else has seen this. If not, I'll try another copy and hope for the best.
Anyone else tried this lens at f/5.6 to f/11 for landscapes? Considering trying another copy... The weird donut of softness is the only reason I got rid of it, really curious if it's an issue shared by all copies of this lens or if I just had a dud.
arduluth wrote:
Anyone else tried this lens at f/5.6 to f/11 for landscapes? Considering trying another copy... The weird donut of softness is the only reason I got rid of it, really curious if it's an issue shared by all copies of this lens or if I just had a dud.
Yes I have the same. From f/2 to f/4 it is perfect. From f/5.6 at little bit unsharp in the center. From f/8, a big "ghost" unsharpness in the center. A shame. Otherwise it is great lens for the money...
jjespdk wrote:
Yes I have the same. From f/2 to f/4 it is perfect. From f/5.6 at little bit unsharp in the center. From f/8, a big "ghost" unsharpness in the center. A shame. Otherwise it is great lens for the money...
It's just so strange, I've never seen anything like that in any lens.
I moved on from the Zonlai 25mm f/1.8 and have tried the Meike 28mm f/2.8. I've been very pleasantly surprised! Unlike the Zonlai, it's capable of edge to edge sharpness for landscapes, basically from wide open. Sharpens up a little at f/4, but the edges are usable right from f/2.8. I've been using it a lot lately.
