Focus issues with K-7

jslifoaw · 08-20-2009, 08:07 PM

I posted this on DPR but will post here too just in case.

I'm on my second K-7 body and cannot get a lot of my lenses under 100mm to focus to infinity. In general, all of my lenses require focusing farther on my K-7 compared to my ist D and K100D. With telephoto AF lenses this is usually not a problem due to their ability to focus past infinity. The problem is that a lot of shorter lenses, especially manual focus ones, are not set to focus past infinity. They're fine on my older bodies, and jamming the focus at infinity works perfectly with said lenses. However my first K-7 had a hugely blurry top half, and my second K-7 has a slightly blurry top half. Inverting the camera inverts the blurriness, stopping down helps, though not fully. Keep in mind I've used manual focus using live view or the OVF with identical results.

It is almost as if the sensor is tilted backwards slightly, or the lens mount is tilting forwards--something that causes the sensor and lens to be farther apart than they should be.

Has anybody experienced this issue or cares to try? It is really obvious with good wide lenses (not so good with the K7).

I am also confident it is not a matter of poor lenses + high res sensor.

Would appreciate some feedback!

rawr · 08-20-2009, 08:35 PM

Pix to illustrate the problem?

There is another thread here about a broken sensor in a brand new K7 and there was also one about a loose focussing screen (or pentaprism) too, so it is not impossible that something has been physically mis-aligned in the guts of your cameras.

jslifoaw · 08-20-2009, 08:45 PM

http://www.strangepics.net/jeremy/IMGP6062.JPG

http://www.strangepics.net/jeremy/IMGP0151.JPG

These are from my balcony. First comes from a K100D, second from a K-7. Same lens, same focus, same aperture (ISO/shutter differ since K100D doesn't have ISO 100)

**jbinpg** · 08-20-2009, 09:15 PM

Does turning off the Auto-level compensation function improve this problem? There was an earlier thread implicating this function.

rawr · 08-20-2009, 10:06 PM

Originally posted by jslifoaw

These are from my balcony. First comes from a K100D, second from a K-7. Same lens, same focus, same aperture (ISO/shutter differ since K100D doesn't have ISO 100)

I don't mean to sound rude, but couldn't you at least shrink those JPG's down to something more manageable. I'm not going to download a 6+ MB JPG just for a 5 second glance.

Especially since my connection is being shaped at the moment...

oldskool · 08-21-2009, 02:08 AM

Originally posted by jslifoaw

These are from my balcony. First comes from a K100D, second from a K-7. Same lens, same focus, same aperture (ISO/shutter differ since K100D doesn't have ISO 100)

I've got the same problem with all my lenses, try to adjust the AF to -7 or -8, it works for me.

jslifoaw · 08-21-2009, 07:17 AM

Originally posted by rawr

I don't mean to sound rude, but couldn't you at least shrink those JPG's down to something more manageable. I'm not going to download a 6+ MB JPG just for a 5 second glance.

Especially since my connection is being shaped at the moment...

I understand, but there are those who insist on having everything be originals, or else people might start suggesting that my problem is that I'm using high compression or not shooting in RAW, etc.

jslifoaw · 08-21-2009, 07:18 AM

Originally posted by jbinpg

Does turning off the Auto-level compensation function improve this problem? There was an earlier thread implicating this function.

Thanks for the suggestion; I never had it turned on to begin with.

jslifoaw · 08-21-2009, 07:24 AM

Originally posted by oldskool

I've got the same problem with all my lenses, try to adjust the AF to -7 or -8, it works for me.

Unfortunately my issue is independent on AF, but I tried it just in case (it didn't make a difference)

08-20-2009, 08:07 PM	#1
jslifoaw Pentaxian Join Date: Apr 2007 Location: Toronto/Victoria Posts: 460	Focus issues with K-7 I posted this on DPR but will post here too just in case. I'm on my second K-7 body and cannot get a lot of my lenses under 100mm to focus to infinity. In general, all of my lenses require focusing farther on my K-7 compared to my ist D and K100D. With telephoto AF lenses this is usually not a problem due to their ability to focus past infinity. The problem is that a lot of shorter lenses, especially manual focus ones, are not set to focus past infinity. They're fine on my older bodies, and jamming the focus at infinity works perfectly with said lenses. However my first K-7 had a hugely blurry top half, and my second K-7 has a slightly blurry top half. Inverting the camera inverts the blurriness, stopping down helps, though not fully. Keep in mind I've used manual focus using live view or the OVF with identical results. It is almost as if the sensor is tilted backwards slightly, or the lens mount is tilting forwards--something that causes the sensor and lens to be farther apart than they should be. Has anybody experienced this issue or cares to try? It is really obvious with good wide lenses (not so good with the K7). I am also confident it is not a matter of poor lenses + high res sensor. Would appreciate some feedback!

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08-20-2009, 08:35 PM	#2
rawr Veteran Member Join Date: Jun 2009 Posts: 11,913	Pix to illustrate the problem? There is another thread here about a broken sensor in a brand new K7 and there was also one about a loose focussing screen (or pentaprism) too, so it is not impossible that something has been physically mis-aligned in the guts of your cameras.

08-20-2009, 08:45 PM	#3
jslifoaw Pentaxian Join Date: Apr 2007 Location: Toronto/Victoria Posts: 460 Original Poster	http://www.strangepics.net/jeremy/IMGP6062.JPG http://www.strangepics.net/jeremy/IMGP0151.JPG These are from my balcony. First comes from a K100D, second from a K-7. Same lens, same focus, same aperture (ISO/shutter differ since K100D doesn't have ISO 100)

08-20-2009, 09:15 PM	#4
jbinpg Site Supporter Join Date: Mar 2008 Location: Prince George, BC Photos: Gallery \| Albums Posts: 3,546	Does turning off the Auto-level compensation function improve this problem? There was an earlier thread implicating this function.

08-20-2009, 10:06 PM	#5
rawr Veteran Member Join Date: Jun 2009 Posts: 11,913	Originally posted by jslifoaw These are from my balcony. First comes from a K100D, second from a K-7. Same lens, same focus, same aperture (ISO/shutter differ since K100D doesn't have ISO 100) I don't mean to sound rude, but couldn't you at least shrink those JPG's down to something more manageable. I'm not going to download a 6+ MB JPG just for a 5 second glance. Especially since my connection is being shaped at the moment...

08-21-2009, 02:08 AM	#6
oldskool Inactive Account Join Date: Aug 2008 Location: Poland Posts: 2	Originally posted by jslifoaw These are from my balcony. First comes from a K100D, second from a K-7. Same lens, same focus, same aperture (ISO/shutter differ since K100D doesn't have ISO 100) I've got the same problem with all my lenses, try to adjust the AF to -7 or -8, it works for me.

08-21-2009, 07:17 AM	#7
jslifoaw Pentaxian Join Date: Apr 2007 Location: Toronto/Victoria Posts: 460 Original Poster	Originally posted by rawr I don't mean to sound rude, but couldn't you at least shrink those JPG's down to something more manageable. I'm not going to download a 6+ MB JPG just for a 5 second glance. Especially since my connection is being shaped at the moment... I understand, but there are those who insist on having everything be originals, or else people might start suggesting that my problem is that I'm using high compression or not shooting in RAW, etc.

08-21-2009, 07:18 AM	#8
jslifoaw Pentaxian Join Date: Apr 2007 Location: Toronto/Victoria Posts: 460 Original Poster	Originally posted by jbinpg Does turning off the Auto-level compensation function improve this problem? There was an earlier thread implicating this function. Thanks for the suggestion; I never had it turned on to begin with.

08-21-2009, 07:24 AM	#9
jslifoaw Pentaxian Join Date: Apr 2007 Location: Toronto/Victoria Posts: 460 Original Poster	Originally posted by oldskool I've got the same problem with all my lenses, try to adjust the AF to -7 or -8, it works for me. Unfortunately my issue is independent on AF, but I tried it just in case (it didn't make a difference)