[Sigmund]

I wonder if old hands can advise on this. The lens just arrived and I'm not sure the manual focus is what it should be regarding feel. Rotating it to infinity there are about eight points at which the ring feels rough and there's slightly increased resistance - almost as if there was a poor indent machining job. There's nothing but smoothness focussing down.

[foto guy]

Sounds like you may have got a lemon.
Or maybe it needs a little "breaking in."

[Sigmund]

Hmm. Autofocus works fine.

[tram57]

I have had one for several years - smooth as silk through out the focus throw either from macro to infinity or visa-vera -- from the outset. I think you must have a defective lens. T

[jatrax]

Mine is smooth all the way. I would send it back as defective unless the stiffness works out quickly.

[Sigmund]

Thanks folks.

Glad I bought it in-country.

[jddwoods]

I wonder if old hands can advise on this. The lens just arrived and I'm not sure the manual focus is what it should be regarding feel. Rotating it to infinity there are about eight points at which the ring feels rough and there's slightly increased resistance - almost as if there was a poor indent machining job. There's nothing but smoothness focussing down.

I noticed that my DFA 100 mm macro makes a slight noise when manually focusing. It is like it is turning a gear mechanism inside the lens, not any kind of binding or stiffness at all. The manual focus is smooth and well damped end to end. I never saw this as a problem. Now I also have DA 35 mm Macro limited and it also makes the same slight gear noise. Hopefully this is all you are observing. Both lenses work perfectly on the camera, autofocus or manual focus and I rate both or them as a 10. If you have unevenness in the feel of the focus ring, you may have a defective lens and should return it. Good Luck.

[Jens Lyn IV]

Mine also grinds very slightly, but with perfect consistency. If there are distinct 'chops' then you could have a crunched-up cog in there. I'd return it.

[Sigmund]

Thanks folks.
There are six other Pentax and one Sigma lenses in the kit and all are smooth. I'll talk with the distributor's technician on Tuesday.

[Sigmund]

To close the loop: I took it in for the tech to look at but he wasn't interested really. Just gave me a new one to have a feel of. Chalk and cheese, so they were swapped. There was probably no functional difference but selling a clunky one wouldn't be straightforward if it comes to that.