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10-07-2010, 11:09 AM   #76
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I've just watched the series of images from Ogl's post, showing the ball being "tracked" by this camera AF toward the photographer ... that is what I had been describing in some posts on this forum: ability to follow, track and keep up with a moving subject toward the camera.

I don't care if they call it tracking, predictive whatever AF, etc ... all that counts is this uncanny ability to stay on course with the moving subject TOWARD the camera.

Soon enough, I hope, PF will have put the K5 through some thourough AF tests and we will be able to determine if the AF has improved, and if so, to what degree.
Let's be patient, again.

JP

10-07-2010, 11:18 AM   #77
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QuoteOriginally posted by falconeye Quote
tigeraction as in "Tiger runs straight towards you"? Maybe, I shouldn't be near you when you're doing wildlife photography

Here's mine - captured on a K10D with FA Limited 43mm/1.9:


Flying condor (so who was it that said you couldn't capture running animals or flying birds unless you have 3D AF or whatever the latest fad is ):
10-07-2010, 11:21 AM   #78
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It should be common knowledge, but anyway:
The ability to track fast moving objects depends on a fast focussing body as well as really fast focussing lenses. I don't see any of the current Pentax lenses being that fast. Maybe the new 18-135, but who knows...
10-07-2010, 11:25 AM   #79
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QuoteOriginally posted by Xatnep_CJ Quote
It should be common knowledge, but anyway:
The ability to track fast moving objects depends on a fast focussing body as well as really fast focussing lenses. I don't see any of the current Pentax lenses being that fast. Maybe the new 18-135, but who knows...
Try the DA40 Limited. It can't get any faster than that... Always choose screwdriven lenses for tracking, SDM is way too slow.

10-07-2010, 11:32 AM   #80
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QuoteOriginally posted by jpzk Quote
I've just watched the series of images from Ogl's post, showing the ball being "tracked" by this camera AF toward the photographer ... that is what I had been describing in some posts on this forum: ability to follow, track and keep up with a moving subject toward the camera.

I don't care if they call it tracking, predictive whatever AF, etc ... all that counts is this uncanny ability to stay on course with the moving subject TOWARD the camera.

Soon enough, I hope, PF will have put the K5 through some thourough AF tests and we will be able to determine if the AF has improved, and if so, to what degree.
Let's be patient, again.

JP
so,the k-7 prediction af is fast enough for cars with good contrast with 80 km/h.but the problem is,in closer distance it will be not in focusrange correctly.
i think,10-15 meters are the stopline for fast prediction.
bigger problem is the lensdrive and the small af point.
the k-5 af processor will be work with the double speed than the old one in k-7.
so my information.
hope the prediction is also much faster.

best regards,andy
10-07-2010, 11:37 AM   #81
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QuoteOriginally posted by zackspeed Quote
the k-5 af processor will be work with the double speed than the old one in k-7.
so my information.
hope the prediction is also much faster.

best regards,andy
Is it only the processor working with double speed or is it the entire AF unit?
I guess doing the calculations is only the smallest fraction of the total focusing time. Any mechanic action might be much much more time consuming.
10-07-2010, 11:38 AM   #82
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QuoteOriginally posted by falconeye Quote
Does anybody have ideas how to seriously test the K-5 new AF system?

I thought of something like this:

D300/1D2 AF test - FM Forums

It looks like a serious test (where the D300 seemed to outperform some Canons). And delivers some stunning photos too.

Any idea how to standardize the setup? Are there any ISO dogs around?
Falk, I have found a few pointers relating to your question but, unfortunately, they are in French.
Here is one anyway, just in case you'd want to have some idea how it's done:

http://www.chassimages.com/forum/index.php?topic=66536.0

and of course, I have still not found the magazine where a series of DLSR's wete tested for AF reliability. But it's there somewhere ... still searching.

JP
10-07-2010, 11:44 AM   #83
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@ Zackspeed:

Haven't you done your private K-5 hands-on-preview today at Hamburg?
Any information or impression you would like to share with us?

10-07-2010, 11:49 AM   #84
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Hamburg is Monday,maybe i get one,maybe not.
iam there for my lenses
the module is better,the sensors are improved and new.the biggest stopper is the af prozessorthe module and the lensdrive.
with the 3 prototypes i couldnt figure out how fast the af was.because they had 0.2 and 0.3 firmware and the bodys were not good adjusted.
but my 1,4 85 worked verry good with open aperture.
little more in focuspoint than my k-7.
live view is a booster,fastest ever.
wait till we have the firmware 1.0.
maybe i can take a new look at monday.

best regards,andy
10-07-2010, 12:20 PM   #85
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QuoteOriginally posted by zackspeed Quote
so,the k-7 prediction af is fast enough for cars with good contrast with 80 km/h.but the problem is,in closer distance it will be not in focusrange correctly.
i think,10-15 meters are the stopline for fast prediction.
bigger problem is the lensdrive and the small af point.
the k-5 af processor will be work with the double speed than the old one in k-7.
so my information.
hope the prediction is also much faster.

best regards,andy
The problem seems to reside in the ability of the AF system to accurately stay on course with smaller objects as well. I usually don't have much trouble with larger subjects moving laterally, however, even a large bird for instance (a heron, which is large enough) coming toward you will likely cause some AF faults at keeping on the subject.
The closer the subject is, the more difficult it is for the AF to follow it, up to a critical point where it becomes an impossibility, at least for the K7.

Hopefully, some of that has been taken care of with the K5 ... I hope so.

JP
10-07-2010, 04:54 PM   #86
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QuoteOriginally posted by jpzk Quote
Falk, I have found a few pointers relating to your question but, unfortunately, they are in French.
Here is one anyway, just in case you'd want to have some idea how it's done:

[ TESTS images Canon 7D vs Nikon D300s ] : un combat de petits géants !
The link is great, et le Francais est genial aussi

Their AF test is similiar to the test I did in my blog which was inpired by a German photo magazine.

Of course, better than none. But I am still unsatisfied by the subjective nature. I believe every AF has a sort of characteristic performance if you would plot accuracy over dM/M/s (relative magnification change speed). Of course, it would still depend on lens, contrast, lighting, background etc. But the characteristics of the curve may not. So, it would be great to have those curves for various AF systems. I fear, it has never been done though.
10-07-2010, 10:45 PM   #87
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QuoteOriginally posted by Xatnep_CJ Quote
It should be common knowledge, but anyway:
The ability to track fast moving objects depends on a fast focussing body as well as really fast focussing lenses. I don't see any of the current Pentax lenses being that fast. Maybe the new 18-135, but who knows...





K-7 with AFC + the fastest AF lens I've ever used (F 135mm)

Last edited by yeatzee; 10-08-2010 at 12:01 PM.
10-08-2010, 11:36 AM   #88
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QuoteOriginally posted by falconeye Quote
The link is great, et le Francais est genial aussi

Their AF test is similiar to the test I did in my blog which was inpired by a German photo magazine.

Of course, better than none. But I am still unsatisfied by the subjective nature. I believe every AF has a sort of characteristic performance if you would plot accuracy over dM/M/s (relative magnification change speed). Of course, it would still depend on lens, contrast, lighting, background etc. But the characteristics of the curve may not. So, it would be great to have those curves for various AF systems. I fear, it has never been done though.
From what I recall from those tests, they plot how many sharp (focused) images are resulting from taken successive shots at high frame rate -burst rate - (for each different camera), in AF-C, while the subject is moving LATERALLY and then TOWARD the camera(s).
So, for instance, a Nikon D3 would have resulted in X-number of focused images during a Y-number of frames, both in laterally moving and oncoming subjects.
The "total number of focused shots" was then compared with other cameras.
Not to my surprise, all Nikon cam's tested were way ahead of the game vs. the other brands. Mind you, they used the likes of D3's, D300 for the tests while, if again I recall properly, a Pentax Kx faced hard competition, to say the least.

Your suggestion seems to go beyond this rather simple test, so I would encourage you to "invent" something in that line of thought!

Cheers.

JP
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