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09-22-2008, 01:06 AM   #1
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AF-A mode ? I can't find any information

What's thisnew mode?
Please, I HAVE to know

Read at
http://www.pentax.jp/english/news/2008/200819.html

'SAFOX VIII'

and

'Thanks to a thorough review of the AF algorithm, this AF system also offers improved autofocusing speed under poor-lighting conditions, in which conventional AF systems take longer to focus on the subject.'

09-22-2008, 01:16 AM   #2
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In AF-A mode, the camera decides whether it's supposed to use continuous or single/static AF.
09-22-2008, 01:19 AM   #3
ibk
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QuoteOriginally posted by thibs Quote

'SAFOX VIII'

and

'Thanks to a thorough review of the AF algorithm, this AF system also offers improved autofocusing speed under poor-lighting conditions, in which conventional AF systems take longer to focus on the subject.'
That's the reason why I think it's SAFOX VIII and a half. Something like a teaser for the upcoming SAFOX IX?
09-22-2008, 04:05 AM   #4
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QuoteOriginally posted by ftpaddict Quote
In AF-A mode, the camera decides whether it's supposed to use continuous or single/static AF.
Wow, that sounds horribly annoying. You think you've got focus locked, and it starts hunting?

09-22-2008, 04:33 AM   #5
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QuoteOriginally posted by mattdm Quote
Wow, that sounds horribly annoying. You think you've got focus locked, and it starts hunting?
Yes, it could be annoying, unless they actually have improved the AF enough to make it work smooth. But remember it's for the first time DSLR buyers, old Pentaxians like us can go to the menu and change so that the AF positions equals single or static autofocus.
09-22-2008, 07:59 AM   #6
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Anyone here that ever had a PZ10, PZ20 will remember "focus tracking". The camera detected in subject was moving and switched autofocus to continous mode.... at least it was what they did in specs, but in real world situations, was a bit annoying.

RB
09-22-2008, 08:36 AM   #7
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QuoteOriginally posted by rburgoss Quote
Anyone here that ever had a PZ10, PZ20 will remember "focus tracking". The camera detected in subject was moving and switched autofocus to continous mode.... at least it was what they did in specs, but in real world situations, was a bit annoying.

RB
Yep, exactly that!

My zx-30 supposedly switched between modes automatically. In practice, though, I couldn't make it switch to AF.C, no matter what I aimed it at.
09-22-2008, 04:44 PM   #8
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If you read the dpreview preview of the K-M it's actually simpler than all that you have three AF modes:

AF-S (Auto Focus Single): The center AF point is selected and only active when you half-press the shutter.

AF-C (Auto Focus Continuous): The center point is selected and on continuous focus mode.

AF-A (Auto Focus Automatic): The camera selects either the center AF point or one of the four alternate AF points based on what it thinks should be the correct focus point.

(IMHO AF-A is the least useful AF option ... though I'm sure many point-and-shoot users will like it because it means they don't have to use their brains and can just blame the camera if the image is poorly focused.)

09-23-2008, 12:05 AM   #9
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Thank you !
09-23-2008, 01:08 AM   #10
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QuoteOriginally posted by ftpaddict Quote
My zx-30 supposedly switched between modes automatically. In practice, though, I couldn't make it switch to AF.C, no matter what I aimed it at.
None of the MZ/ZX-bodies had AF-C.
All of them had AF-S with predictive AF, not AF-C but predictive AF-S.
09-23-2008, 01:43 AM   #11
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QuoteOriginally posted by JJJPhoto Quote
If you read the dpreview preview of the K-M it's actually simpler than all that you have three AF modes:

AF-S (Auto Focus Single): The center AF point is selected and only active when you half-press the shutter.

AF-C (Auto Focus Continuous): The center point is selected and on continuous focus mode.

AF-A (Auto Focus Automatic): The camera selects either the center AF point or one of the four alternate AF points based on what it thinks should be the correct focus point.
Where do you read that? I reviewed dpreview preview of K-m and haven't found anything like that.

BTW, your description of AF-A sounds like description ow "Wide mode" of AF point selection setting.
09-23-2008, 03:23 AM   #12
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If allowed I am going to trow my 2 cents in this matter:

AF.A does essentialy only one thing: tries to react to whatever it thinks the user will want. Case in point: you're in AF.S and lock focus than change (no matter if only a slight recomposition or across the room). The focus point will remain locked unless you lift the finger and re-press half way.
With AF.A enabled wherever you end up the camera will refocus on that point.
This will probably encourage people to use all focus points rather than lock and recompose with the center one only. Again this is the default setting for AF one can easily select from the menu one of the other "classic" 2. And in my informal usage (v 0.2 firmware remember) the camera felt snappy and fast in focusing.

One last thing the beta cameras had no possibility of selecting manually the AF points (hence ogl's nervous breakdown related to this subject). And also related to this firmware thing the samples published are light years away from what the beta camera could do especially in exposure and colors.

Regards,
Radu
09-23-2008, 12:51 PM   #13
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QuoteOriginally posted by RaduA Quote
If allowed I am going to trow my 2 cents in this matter:

AF.A does essentialy only one thing: tries to react to whatever it thinks the user will want. Case in point: you're in AF.S and lock focus than change (no matter if only a slight recomposition or across the room). The focus point will remain locked unless you lift the finger and re-press half way.
With AF.A enabled wherever you end up the camera will refocus on that point.
Hmm, your description sounds like AF-C
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