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12-28-2009, 09:09 PM   #16
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QuoteOriginally posted by LightBug Quote
I hope selectable focus points for manual lenses become available for K-x via firmware upgrade.
Not likely. Every single Pentax DSLR for the last five years has had this same limitation when using manual focus lenses. If you want to focus on something off center and it's one of those rare times focus-recompose introduces a noticeable error, you just have to focus by eye.

12-29-2009, 03:59 AM   #17
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The example in that link is rather very extreme. It shows a head and shoulders portrait (recompose would be about 5-8", which would be still ok) but then calculates for an entire model. But the working distance would be quite large then.
In fact, if you recompose by such a large amount (about 20" for 72" distance), you might very likely introduce another problem, of not getting the object into the plane of focus.
A good alternative can be to center-focus and crop instead.

In fact, if you work out the math, as you cram more and more object into the FOV, your DOF necessarily becomes larger (because you are further away or have a wider lens), thereby reducing the criticality of focus recompose.

The big mistake of the linked article is that it throughs out numbers (2" longer distance) that have nothing to do with taking a picture shown (100mm F2, head and shoulders distance).

So, the issue is much smaller than generally regarded - although it does exist. But a much larger issue can be to not align the optical focal plane with the object. Similar problem, but has nothing to do with center-focus recompose.
12-30-2009, 01:07 PM   #18
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QuoteOriginally posted by LeoTaylor Quote
Seriously, I switched to spot focus when I discovered I could not focus on a bird in a tree. The camera tried to grab a foreground or background branch. I have never enabled multi-point focus since. But, other people use that feature so I'm glad they have the option.
That's the reason why I eventually bought a dSLR. Took an Olympus UZ500 on holiday as my only camera; this is a camera with quite some features including spot focus (hidden away in the menus). Unfortunately it forgets that setting when it goes into sleep mode so a quick shot of wildlife after that is doomed
01-01-2010, 04:00 AM   #19
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QuoteOriginally posted by tkelly Quote
I had the same problem with my K10D, but my K7 allows selection of focus point for manual focus confirmation. This is one of the improvements I really appreciate. I am surprised this has not received more attention.
so maybe tkelly can confirm us once more again, about whether K-7 have capability to select focus point when we using manual lenses..



or maybe im the one who read it wrong..?

01-01-2010, 04:33 AM   #20
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QuoteOriginally posted by LightBug Quote
Is there a technical reason why is this the case?
I speculated about it a long time ago in a thread concerning lens limitations. This thread also contains a report about a K200D using all AF points with a manual lens. Perhaps some manual lenses somehow enable multiple AF points but most do not?
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