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03-23-2008, 07:59 AM   #1
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do you have focus problems with 16-45???

here are some photos...
i rarely get some pictures like the uploaded ones.
i still could not understand from what problem my lens suffers.
i don't think it is focus problem because of low light because i rarely get problematic pictures under the sun light...
is my 16-45 a bad copy???

thanks
halil

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03-23-2008, 08:01 AM   #2
hll
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1 photo: our guests from texas, they have turkish hats..
2 photo: my family and our american guests...
i think i won't share these photos with them....
03-23-2008, 09:50 AM   #3
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Looks unfocused.
Do you have your Shake reduction off? I usually forget to switch it back to SR sometimes and I get some out of focus shots this way.
03-23-2008, 10:37 AM   #4
hll
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no, sr was on...

03-23-2008, 10:38 AM   #5
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I have had the 16-45 for about 2 months and had no problems at all. The only time it had a hard time focusing was at a car show about a week ago, but that was understandable.
03-23-2008, 10:50 AM   #6
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Looks like the focus were right in the middle on both shots. Did you let the camera choose the AF point?
03-23-2008, 11:38 AM   #7
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what iso, what f-stop, and how far are you from them? Multi point or single point focus?

My 16-45 has been a great lens. I always use single point AF, center what I want to focus on, then move the camera to frame the shot. I also go up to 1600 indoors and SR is always on.
03-24-2008, 01:10 AM   #8
hll
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the photos above were taken at higher than 1000 iso, 16mm, sr on and single point.
sr is always on when i take photos.
i really can't find a common points (exif) of my problematic pictures...
the other issue is i really have problems with my circular polarizer !!!!
rarely i have good photos when it is on the camera. (focus problem again)
i tested the same polarizer with my 50-135 and i got no focus problem or much less!!
halil

03-24-2008, 01:13 AM   #9
hll
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one more thing
(just a belief) if i wait a little (1-2 seconds) after the green light (focus indicator) is on, the pictures are ok.
03-24-2008, 03:26 AM   #10
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The exif data says that both photos were taken at f/4 and 1/30 sec. The first one at 19mm and the second one at 16mm.
03-24-2008, 04:31 AM   #11
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I had a 16-45. I still have buyers remorse for selling it. It was a great lens in daylight and with external flash, but a low light lens it was not.
03-24-2008, 07:21 AM   #12
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Wide open your DOF will be its narrowest, but then your shots were at a pretty wide angle. Perhaps what's causing this is a combination of factors - 1) your focus point is in the middle/towards the rear of the subjects and 2) your camera may have a bit of back focus. Put these together and you'll be out of focus towards the front.

While in most situations my 16-45 focused well enough, I've noted that on my K100d the focus point always was a bit behind what the camera indicated. Depending on how closely I looked and the aperture, I would notice the back focus with the 16-45. This was worse with manual focus lenses. Over the weekend I went into the dread menu to adjust the focus a tiny bit, which so far has improved things considerably.
03-24-2008, 08:09 AM   #13
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I am a newbie, so take it with a grain of salt.

In low light situation, autofocus does not come immediately, and when you let the shutter go before the AF is locked, you are asking the camera to take the picture anyway (even if it is not focused properly). By looking at the two pictures, you are making the camera work hard since you have it in AV mode combined with spot metering. Also, the AF point on the first picture is on the person's dark shirt on the left; while the AF point on the second picture is on the person's hat in the back rather than his face.

Try the same setting in manual mode 1/30 and F4 - let the flash adjust the output and give the camera a break. Also, in the first picture, I think it is a focus error; in the second picture choose the AF point closer (e.g. front row lady in the middle) and put the AF point on the face - something which is more contrasty and easy to get focus lock. With FLs at 16 and 24mm, the DOF is pretty wide, so everyone in the picture should be in focus. Again, without the focus confirmation from the camera, you should not expect sharp images at all (I think it is a reasonable assumption).

If it does not make sense to you, please ignore me.
03-24-2008, 08:19 AM   #14
hll
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as soon as possible i will upload some photos taken under strong light...
but i am glad nobody said it is a common issue...
03-24-2008, 09:59 AM   #15
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I have this lens and it is on my camera more then half the time. Specifically family events as you have here. I can't figure what happened here. What flash did you use?
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