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10-03-2008, 02:50 PM   #1
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Stupid DA★50-135mm F2.8 ED question

So an unexpected errand took me this morning in range of B & H, always a dangerous thing, and I finally decided to pick up the DA 50-135 for portraiture. (An aside: the guy selling it to me was bored with showing me -- I asked to try it out, he brought me a sample, I said I'll take it, but sold me "brand new in the box" another one, all in the same "whatever" monotone, just clocking time).

Now this is my first real zoom (sold the kit a long time ago), and my first SDM lens, so I'm wondering, after playing with it a while, if the learning curve from primes to zooms really is steep. Focus seems to be erratic. I hear the motor whirr a bit, but not much "snapping" or "popping" into place.

Test shots are all over the place.

So I check the manual focus: the barrel just spins and spins, no "catch," the distance indicator doesn't move.

I've got a bum copy, right? Or am I just zoom-stupid? I don't have anything to compare it to.

10-03-2008, 03:10 PM   #2
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sounds like something is really really wrong. If the quick shift doesnt stick thats clearly not right.
Go back to the shop and try out a few different copies and make your mind up?
10-03-2008, 07:47 PM   #3
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Not accusing you of anything, but is the switch on the lens set to MF or AF? If it's on AF, the focus ring should just spin and spin without any effect on focus. I always forget to do this on my Tamron 90mm macro... I either get an ugly grinding sound if the body's set to AF and the lens is on MF (since I'm winding the focus mechanism as well as the lens) or I spin the ring and nothing happens (body is on MF and the lens is on AF).

Kind of embarrassing
10-03-2008, 08:16 PM   #4
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manual barrel keeps turning is normal, both my DA* lenses do this. also the sound you are describing sounds right. its real quiet. its weird at first if you are used to regular screw focus lenses. just listen for the focus beep

10-03-2008, 08:19 PM   #5
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QuoteOriginally posted by a a i b Quote
So an unexpected errand took me this morning in range of B & H, always a dangerous thing, and I finally decided to pick up the DA 50-135 for portraiture. (An aside: the guy selling it to me was bored with showing me -- I asked to try it out, he brought me a sample, I said I'll take it, but sold me "brand new in the box" another one, all in the same "whatever" monotone, just clocking time).

Now this is my first real zoom (sold the kit a long time ago), and my first SDM lens, so I'm wondering, after playing with it a while, if the learning curve from primes to zooms really is steep. Focus seems to be erratic. I hear the motor whirr a bit, but not much "snapping" or "popping" into place.

Test shots are all over the place.

So I check the manual focus: the barrel just spins and spins, no "catch," the distance indicator doesn't move.

I've got a bum copy, right? Or am I just zoom-stupid? I don't have anything to compare it to.
I have the 50-135 on my k10d at this very moment. To test out your lens:
  • Turn the focusing ring. You should be able to change the focus distance indicator on the lens by turning the ring in the appropriate direction.
  • The focus ring will NOT stop at the end, but keep on going. This is an effect of the MF touch up capability of the lens.
If the ring does not affect the focus distance, it is a dud.

  • Having passed the above test, make sure that both the lens and the camera are in AF.S and press the shutter release.
  • The lens should focus, or at least attempt to. It might range all the way out and then back again.
If the lens fails the above test, remove it and re-install it a few times, and try again.

If it still fails, use a microfiber cloth with a drop of denatured alcohol on it to clean all the contacts on the camera mount and on the lens mount. Try again, making sure that the lens is firmly in place - an attempt to remove it without pressing the lens release will do nothing.

If it flunks all the above, take it back.

When I first received my lens there must have been something on the contacts. AF was erratic. I cleaned the contacts on the camera lens mount, and the two power contacts for the SDM inside the mount, then cleaned the contacts on the lens. I used a microfiber cloth lightly dampened with alcohol. It has worked flawlessly since then.
10-03-2008, 09:44 PM   #6
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Also, I don't know your camera but there are some other things to see to first:

(1) If you have a K10D, make sure your firmware is 1.3 (or 1.03, or whatever).
(2) If you have a K100D Super, a K200D, a K20D, or a K2000D (or whatever), it should probably work.
(3) If you have an older camera, then SDM may not work on your model.

I think you can hold down the menu button when starting a K10D to determine the firmware revision. I don't have a camera in front of me.
10-03-2008, 10:08 PM   #7
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QuoteOriginally posted by Aegon Quote
Also, I don't know your camera but there are some other things to see to first:

(1) If you have a K10D, make sure your firmware is 1.3 (or 1.03, or whatever).
(2) If you have a K100D Super, a K200D, a K20D, or a K2000D (or whatever), it should probably work.
(3) If you have an older camera, then SDM may not work on your model.

I think you can hold down the menu button when starting a K10D to determine the firmware revision. I don't have a camera in front of me.
Thanks, Aegon! I completely forgot that you need the 1.30 firmware on the k10d to get SDM. However, it would just screw focus with earlier releases. Apparently the lens just was not focusing at all. And, yes, hold the menu button when turning on the camera to see the firmware level.
10-04-2008, 01:15 PM   #8
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I've got a K20D, I certainly played with the AF/MF switch on the lens, etc.

QuoteOriginally posted by Canada_Rockies Quote
If the ring does not affect the focus distance, it is a dud.
^This. Turning the focus ring seems to have no effect on the distance.

I left the lens at work. On Monday I'll make sure I'm not crazy and try and find time to trek back uptown.

10-06-2008, 08:25 PM   #9
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Cleaned the contacts, no go. Took it back to B&H for an exchange, and this time, tested the lens before I left the store.

The replacement lens seems to be good. Gotta say, though, the hood (threading) seems flimsy.
10-06-2008, 08:47 PM   #10
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Great feedback guys. This responses on this forum never cease to amaze me...
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