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Old Dec 31, 2006, 7:18 PM   #1
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I've done some more testing with the K10D and it seems as if the viewfinder image doesn't agree with the sensor's position - ie when the image is focused manually, the captured image is slightly blurred. Much better results are obtained wit the auto focusing but infinity still can't be reliably acquired. (maybe once every 6 shots, will give a sharp infinity). If the camera is set to infinity manually, this gives a very, very unfocused image for objects at infinity.

Having sad all this, I went to a rock pool yesterda and took pics of people jumping into the water. The fact that the camera has such minimal delay, allowed me to capture (and freeze) the jumpers really well. This camera has the potential to be really good. I suspect that the fresnel screen is fractionally tilted or the bayonet isn't shimmed correctly. I'll keep this group posted of my experiences. In the meanwhile, here's a sample pic
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Old Dec 31, 2006, 8:23 PM   #2
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irivlin wrote:
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I've done some more testing with the K10D and it seems as if the viewfinder image doesn't agree with the sensor's position - ie when the image is focused manually, the captured image is slightly blurred. Much better results are obtained wit the auto focusing but infinity still can't be reliably acquired. (maybe once every 6 shots, will give a sharp infinity). If the camera is set to infinity manually, this gives a very, very unfocused image for objects at infinity.
Have you adjusted the diopter setting on the viewfinder? Having that set correctly is important for manually focusing the camera.

I'm not actually able to produce good manually focused shots every time with the K10D either, but I believe that has to do with being used to the split image focusing aid on my old Ricoh... I may just invest in one of the Katz-eye focusing screens when they become available. Of course, I haven't actually produced any manually focused images that were so out of focus I decided they had to go, so I guess I'm producing results I'm happy with.

There are other factors that can lead to slightly blurred images when you're manually focusing, camera shake being a prime candidate. If you didn't have SR on or have the camera on a tripod or monopod, check and see how long the shutter was open for.

Also, IMO, focusing on objects at infinity is a poor test for focusing acuracy. There is always some limit as to the distance at which a lens can accurately focus on an object, i.e. even though the focusing ring says infinity, it really just means the maximum distance the lens can focus at. Also, the aperature setting may be set too low to provide good depth of field (remember, you get more depth of field with higher aperature settings).

Paul
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Old Dec 31, 2006, 8:56 PM   #3
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The camera you have sounds very suspicious. I'd say check the dioper if something looks in focus when the picture isn't, but am at a loss as to why the camera wouldn't autofocus to infinity. Actually, I DO have a thought about the infinity problem, but don't understand why it would be a hit-or-miss thing. Having played with extension tubes, and after reading about some screw mount adaptors, if the lens isn't set correctly, you lose infinity focus. Your idea that the bayonet isn't shimmed right makes sense - if it were out a bit it would be acting like an extension tube. But wouldn't it always be OOF at infinity, not hit-or-miss?

I can say that I don't have any of these problems with my K10, so I'd be talking to Pentax about repair/new camera - it doesn't sound like normal behaviour to me at all.
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Old Dec 31, 2006, 9:26 PM   #4
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irivlin wrote:
Quote:
I've done some more testing with the K10D and it seems as if the viewfinder image doesn't agree with the sensor's position - ie when the image is focused manually, the captured image is slightly blurred. Much better results are obtained wit the auto focusing but infinity still can't be reliably acquired. (maybe once every 6 shots, will give a sharp infinity). If the camera is set to infinity manually, this gives a very, very unfocused image for objects at infinity.

Having sad all this, I went to a rock pool yesterda and took pics of people jumping into the water. The fact that the camera has such minimal delay, allowed me to capture (and freeze) the jumpers really well. This camera has the potential to be really good. I suspect that the fresnel screen is fractionally tilted or the bayonet isn't shimmed correctly. I'll keep this group posted of my experiences. In the meanwhile, here's a sample pic
Hmm if I can take that sort of pict, I will be happy. Irivlin, great shot whatever focusing issue you have. Ok you guys/gals can continue whatever you have been doing.

Daniel
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Old Dec 31, 2006, 9:27 PM   #5
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this is easily resolved. if the cam has the problem you state, return it or send it to pentax repair explaining your problem.. it's in warranty!! if i remember right , it's not even your cam..

roy
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Old Dec 31, 2006, 10:05 PM   #6
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sorry i posted to this thread!!
i realize that it's best not to respond to trolls...

roy
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Old Jan 1, 2007, 4:56 AM   #7
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robar wrote:
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sorry i posted to this thread!!
i realize that it's best not to respond to trolls...

roy

Troll or no troll?

Does not matter to me. What matters is the pict.

irivlin, keep posting pict . You have another pict of the vintage MG?

I envy your friend who must be a lucky fellow owning a sought after K10D. And a photographer as well

Daniel

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Old Jan 1, 2007, 10:45 AM   #8
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I dunno, picture seems fine to me. Good depth of field of everything from Citroen (?), next car (Renault ?) and building in the background.

If you focused on the Citroen sedan's grille I could see that being a problem as that grille is one complicated bit of parts, some just a little further away than the rest. I could see that confusing the focus sensors.

Nice pix the way it is.
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