DA 70mm f2.4 - play in barrel

I recently purchased a DA 70mm ltd lens and have noticed that there is play in the barrel ever though it only extends a short distance it is noticeable both side to side and forward and back. Much more than my 50mm lens. Is this normal. As this lens is supposed to be of a high build quality I think not. If some of you owners of this lens could tell how your lens is it would be much appreciated.

Mike

I don't have this lens, but I used to have the excellent 24-90 zoom. It is normal for that lens to exhibit alarming wobbliness and yet the pictures were always fine.

Perhaps both had the same lens designer.

G

Thanks for your comments. i am concerned because I have had my camera lens checked by Pentax and after backfucusing adjustments and the second time front focusing adjustments and thirdly told it's ok. The focusing is inconsistant - sometimes it's incredibly sharp and others soft and not centered. Settings the same of course. f2.4,iso 100 ,good day light, center point. Could excessive play cause this inconsistency?

Mike

I get this all the time with my DS, inconsistent focusing with various lenses. I think it's the camera. What camera do you have.

I'm sure it's the camera. We had two *istDS bodies and both were spot on with all lenses.

Are you using centre-spot only focus? Multi-point can be a bit annoying.

I have the same lens George (24-90). Great pictures from it, though it can be a bit disconcerting when you point the camera at the ground and the lens "auto-zooms" by itself at alarming speed !!

i get more consistent focussing with my old DS than with the K10.

What do people mean when they say "consistent focusing"?

Is it:

- speed of AF lock
- focus accuracy in final image
- lack of hunting in low light
- something else?

I never had an AF SLR prior to the K10D, so I have nothing to compare it with.

What I have noticed in the 18 months I've had it, is that my ability to get the AF to do what I want (whatever that happens to be) seems to have improved enormously, and I'm not entirely sure what I'm doing differently.

Good question. I would say it means the system locks on instantly to the correct point of focus. And then the shutter releases with a continuing press of the shutter release.

In this case it could also be explained as more reliable focusing !

Martin.

One of the reasons I thought that I was getting inconsistent focusing was because of what I read in the link below. Even though its is a different lens it could still be relevant.

link

In good conditions my 50mm lens in centre point focusing is much more consistent than this 70mm lens. My point is that when I read the Pentax bumph about how these ltd lenses are built to a higher standard with specially selected materials I do not expect the barrel to have a sloppy fit. It's poorly made and should be replaced. I took it back to Pentax and even though the technician agreed that it had too much play. They would not replace it because it is a month old. So now they have it and will try to fix it.

So while they have that lens I've reverted to using my 50mm lens which love using anyway.

Mike