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04-04-2010, 06:28 AM   #16
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How sturdy is your tripod?
Was there a breeze?
Does the floor have even the slightest give as so many modern structures do?
What is a FAT tree?

One last try. One step at a time.

Set the focal length to 18mm.

Open your aperture to f3.5. (That is as wide as it will go.) O
Set the focus ring to infinity (∞).
Take a picture being certain that nothing moves the camera.

Now set your aperture to f8 (that is a smaller aperture than f3.5.) o
Make sure the focus ring is still at infinity (∞).
Take a picture being certain that nothing moves the camera.

Next set your aperture to f22 - The smallest aperture on your lens.
Make sure the focus ring is still at infinity (∞).
Take a picture being certain that nothing moves the camera.[/U]

To carry your test even further -----

Repeat the above steps exactly with the focal length set at 35mm and the again at 55mm.
You will find that as you increase the focal length the maximum aperture will decrease (get smaller) to f4.5 and to f5.6. That is the nature of most lenses. It will cause the exposure times to increase in order to maintain the correct exposure.

One other thing. Do not focus by looking through the viewfinder. Just set the ring at ∞ and forget about what the viewfinder shows.

Good luck.

Mickey

04-04-2010, 06:53 AM   #17
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Original Poster
here it is
full size zipped.
exif all inside.

http://www.4shared.com/file/25665442...70f/photo.html


on tripod
is off
timer 2sec
f3.5, f6.3, f13
iso 200
Manual focus (resulting in infinity focus) using live view 10x magnification.
How i do? i select widest aperture which is f3.5, use live view 10x to focus at the jumping board. then shoot n change to f6.3 and then f13.
Focus at the jumping board of the swimming pool(center of the pic)

the whole content of the photos are far enough to be in the hyperfocal zone of my kit lens at 18mm. so any F-stop produce almost no difference. juuuuuust a bit blur in the f13, could be diffraction like labert'd said. i tired RAW and same result.
04-04-2010, 07:03 AM   #18
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Photos look normal to me.
04-04-2010, 12:17 PM   #19
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learnphotography,

Could you please send your photos the normal way so that I can see them.

Mickey

04-04-2010, 04:59 PM   #20
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QuoteOriginally posted by learnphotography Quote
here it is
on tripod
is off
timer 2sec
f3.5, f6.3, f13
iso 200
Manual focus (resulting in infinity focus) using live view 10x magnification..
you might get better technical support from pentax customer service. send them the files and have them troubleshoot your gear. it sounds like you're still under warranty...
04-04-2010, 11:32 PM   #21
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Posts: 4,571
Is there a cheap UV filter involved here? Photos seem very blurry.
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