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07-10-2016, 05:26 AM   #46
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In FF Mod, set AF.C to 9 Auto and keep your subject in the crop frame where the AF points are concentrated. If you let your subject move out of the focus frame AF goes to infinity, then has to reacquired focus when the subject comes back into the frame.

At least for me using this tiny bit of t chinquapin to work with the hardware I am given solves most of my tracking AF failures.

07-10-2016, 06:07 AM   #47
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QuoteOriginally posted by monochrome Quote
In FF Mod, set AF.C to 9 Auto and keep your subject in the crop frame where the AF points are concentrated. If you let your subject move out of the focus frame AF goes to infinity, then has to reacquired focus when the subject comes back into the frame.
.
This is where the Hold setting becomes important. If your technique is shaky and you let the subject stray repeatedly outside the points, this needs to be cranked up.

Again - perhaps DPR were guilty of this - you need to keep the subject within the focus point area.

That's traditionally easier to do on an APS-C DSLR because that proportion is usually bigger.

PS A problem with Auto 9 or whatever is that the bike's handlebars will be closer to you than the cyclist's face.
07-10-2016, 06:48 AM   #48
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Just curious. From the Pentax website: -
PENTAX Real-time Scene Analysis System

This RICOH-original technology is available during viewfinder shooting when the exposure mode is set to Scene Analyze Auto and the Custom Image mode is set to Auto Select.

Has anyone used continuous autofocus with above settings.

Jeff
07-10-2016, 06:59 AM   #49
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Clackers, thank you for your real world explanation of the hold function. Quite frankly I still find the whole area of auto focus options bewildering to say the least. For me personally all the uproar on this site over the DPR review of the K1 has provided me with a gold mine of knowledge about how exactly autofocus works on a Pentax DSLR. When I went digital in 2012 it was also my first experience with auto focus and it has bewildered me ever since. Before that all my lenses were manual focus so even on my PZ-1p I never used it.

07-10-2016, 07:13 AM - 1 Like   #50
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QuoteOriginally posted by clackers Quote
This is where the Hold setting becomes important. If your technique is shaky and you let the subject stray repeatedly outside the points, this needs to be cranked up.

Again - perhaps DPR were guilty of this - you need to keep the subject within the focus point area.

That's traditionally easier to do on an APS-C DSLR because that proportion is usually bigger.

PS A problem with Auto 9 or whatever is that the bike's handlebars will be closer to you than the cyclist's face.
When the camera is mounted on a tripod you have no control to keep the points on the subject. At f/2.8 nothing can keep the handlebars and the face simultaneously sharp. They re-ran the test with AF.C (M) 9-S and put the S point on the cyclists head for the first shot - still got bad tracking AF.

I exchanged a number of civil messages and posts with Rishi and Chris. I don't think they're out to 'get' Pentax. I do believe they have an inflated sense of their position as a source of information and guidance to consumers, and they're convinced they are right, but they both respond politely to civil questions and suggestions. I disagree with their conclusions, as is my right [above added after some further thought 01/24pm Sunday]

This is what I think happened in the test.

The test was designed to rate predictive tracking autofocus across the entire image area. The Pentax autofocus sensor was designed for APSc cameras; the focus points are concentrated in the center of the image area (within the crop frame) leaving wide areas of the image area without AF points.


The bicycle weaved in and out of the focus frame (the crop frame). When the bicycle left the focus frame the camera went to infinity. When the bicycle came back in it took the camera time to reacquire focus - and then the bicycle went out the other side . . . .

There are too few (3) f/2.8 cross-type focus points (of 25 total cross-type) so at f/2.8 the only time focus acquisition is quick is when the bicycle is in the exact center of the viewfinder. If you use Hold 3 the bicycle moves itself out of focus when it is out of the focus frame. Ergo, DPR says only 15-20% of the captures were in focus - they actually may be correct, even though Falk Lumo says there has to be a problem with the gear. Falk says no modern dSLR achieves a tracking AF.C 85% failure rate.

The problem for K-1 on that test - and it's a real, actual fault of the Pentax AF.C system and physical properties - is there is no possible technique to compensate when the camera is on a tripod. K-1 was destined to perform poorly on that test. The test actually, correctly demonstrates a shortcoming of the Pentax tracking AF.C system.

My point is, so what? That test is not meaningful as an indicator of real-world competence of the camera. Failing that test does not mean the entire AF system is Poor (their rating). Further, to then conclude the K-1 is not suitable for burst-photographing small, active children is not a supportable conclusion. In the real world, who takes action photographs of small active children at f/2.8 from a tripod?

What we now know is, the K-1 was not designed to pass this kind of test. And that's all we know.

IMHO, since they have a Ph.D. writing camera reviews, they should have explained the cause of the failure and offered some suggestions to correct for it using technique if a buyer wants to, for instance, burst-photograph small, active children.

Last edited by monochrome; 07-10-2016 at 11:42 AM.
07-10-2016, 08:05 AM   #51
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I hope Pentax puts you on retainer monochrome. I am surprised that Pentax hasn't chimed in. It seems it would be worthwhile for Pentaxx to provide some on site assistance to help reviewers conduct tests and a repeat of the DPR autofocus test to present a fair evaluation relative to the camera's capability. The user manual is skethcy at best when it comes to explaining autofocus. The likelihood of a reviewer being knowledgeable about Pentax is probably low. In addition to the DPR methodology this review is also in part due to Pentax's poor marketing and an AF system that while OK needs to get a lot better for tracking relative to competition.
07-10-2016, 08:24 AM - 1 Like   #52
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QuoteOriginally posted by RockvilleBob Quote
I am surprised that Pentax hasn't chimed in.
I don't think they would dare to get involved in the snake pit of dpreview comments. What can they say about it if it is met with what I think is incompetence. I think the K-1 has an adequate tracking system for general use, but they are attacking it at it's Achilles heel and then generalise the result to the entire AF system of the camera. Same for testing low light with a Sigma (notorious for poor cooperation with camera's because of their backwards engineering) and then implying Pentax is lying about AF sensitivity. Pentaxians here and over there are confirming that with countless examples of sharp action shots. But still Dpreview thinks it is a camera best used in a studio or for landscapes. That is an oversimplification just because they need to put it in a box, when in fact it is a great all-rounder which strengths lie more towards those area's but which can just as easily be applied in other areas of photography if you just take into account certain limitations.
07-10-2016, 09:34 AM - 1 Like   #53
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QuoteOriginally posted by monochrome Quote
The test was designed to rate predictive tracking autofocus across the entire image area. The Pentax autofocus sensor was designed for APSc cameras; the focus points are concentrated in the center of the image area (within the crop frame) leaving wide areas of the image area without AF points.
Completely ignoring the dpreview review and only looking at the schema and your explanation, this AF design is a huge issue for me.

I don't care honestly of much tracking and predictive AF even if I would be happy to have something better.

But I use regularly off center AF point to focus on the eye for example. I don't want to do MF to take a simple portrait... And that funny but the AF point are too much in the center. On the K3, I can basically put the eye rougly near the rule of third. On that K1 I cant't in FF mode. The D750 is better on that aspect but not great.

Overall APSC bodies are much better for that as well as mirorless bodies.

That may sound stupid, but that a reason for me to not buy that K1.

07-10-2016, 10:18 AM   #54
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QuoteOriginally posted by jpzk Quote
... Blah !
Not really worth reading.
Thats not correct.
In my opinion there tenor is negativ in some points, but the facts - not their wording - are true. Overall the review was fair and complimentary.

And they have a big problem with their continuous tests, which is faulty - I think mainly because the have no one who is intimate with the pentax K- models.
And their are not honest about their pictures and the way they do it. (exchanging pictures without notice. They are not responding to concrete question, about distances and where they had the focus)

Insisting in their schooling and telling that their a right like a Rumpelstiltskin isn't the best way to communicate.

I think they lost a lot of reputation with this second curious test with pentax systems.
07-10-2016, 11:37 AM   #55
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QuoteOriginally posted by Nicolas06 Quote
Completely ignoring the dpreview review and only looking at the schema and your explanation, this AF design is a huge issue for me.

I don't care honestly of much tracking and predictive AF even if I would be happy to have something better.

But I use regularly off center AF point to focus on the eye for example. I don't want to do MF to take a simple portrait... And that funny but the AF point are too much in the center. On the K3, I can basically put the eye rougly near the rule of third. On that K1 I cant't in FF mode. The D750 is better on that aspect but not great.

Overall APSC bodies are much better for that as well as mirorless bodies.

That may sound stupid, but that a reason for me to not buy that K1.
If you look at the points diagram of the K-1 with the K-3 and compare them in a relative fashion, while the two lone edge points are slightly farther out on the K-3 (one more AF column over -- the leftmost point on the K-3 looks to be at the 25% position, and about 30% on the K-1), the center points are all equivalently placed and the K-1 has an extra mini-column (3 point column) between the center points and the edge points that the K-3 doesn't have. So the K-1 has the same points in the center, and a few extra points connecting the center to the edges. But the edges are slightly closer in.
07-10-2016, 01:17 PM - 1 Like   #56
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I think I have read as much as I could find about this subject over the last 3 days that my eyeballs are bleeding! I don't think Dr. Sanyal did anything nefarious in the test/editing of the K1. I am a technical professional with a graduate degree in Radiography/Radiation Physics(NOT a PHD) so I can understand his point of view and the scientific method. I think being consistent in DPR's testing with out snarky quips and with a bit more disclosure of lenses used/methodology would go a long way for many of us and help us to understand what was happening. I used a Nikon D3X for three years which had Nikon's 1st generation of the 51 point AF system that many are referring to here in the Nikon D750. I just went into about 5000 images exif files to see what it was doing with tracking, especially with moving people both fast and slow. Even with the old 51 point AF it's hit rate was/is remarkable without much intervention from me. The K1 will track, but I have to keep the AF point on the target( I rented the thing with the 24-70 lens; we own the K3 and K3II), where the D3X did most of that itself. It appears that the K3, K3II, K1 do not have much of an ability to lock on and track BY ITSELF, but it works much better if you track and keep the AF point where you want it to focus. One thing that the Nikon 51 point system is superb at is locking onto a face and tracking that face with the optical view finder, and for weddings this can really lessen the workload on the photographer. Yes the most modern Pentaxes do wedding shoots very well, but it will take more effort. The Pentax AF may simply need a more powerful processor, or even two processors to really excel, but I don't know that for sure. I switched because my wife has small hands and needed a rugged weather resistant camera that did not weigh a ton for the lenses. I MAY need to switch back to the Nikon(D750) as my need for a faster AF with facial recognition is starting to outweigh my need for more MP(24 vs 36) and the other goodies that the K1 offers. Karen will stay with APSc Pentax and will probably never switch. Ymmv but this is how I see this now, and time to move on.

David
07-10-2016, 01:45 PM   #57
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The more I see report here the more in the end I understand that even the old 51point AF that appeared 8 years ago on Nikon bodies is still superior. The K3 an K1 are able to track but everybody with an actual experience explain that it is just easier on a Nikon.

Experimented Pentax users get good results, but this doesn't comes from the Camera feature but rather their technique. Because theses experiences guy get good result they think their camera of choice is perfect and there no much difference.

What I really grab here is that if somebody ask for great AF, in particular if he has issue on his current hardware, you should still advice Nikon, not Pentax. Because the Nikon are more intuitive to use on that aspect.
07-10-2016, 02:04 PM   #58
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QuoteOriginally posted by Nicolas06 Quote
The more I see report here the more in the end I understand that even the old 51point AF that appeared 8 years ago on Nikon bodies is still superior. The K3 an K1 are able to track but everybody with an actual experience explain that it is just easier on a Nikon.

Experimented Pentax users get good results, but this doesn't comes from the Camera feature but rather their technique. Because theses experiences guy get good result they think their camera of choice is perfect and there no much difference.

What I really grab here is that if somebody ask for great AF, in particular if he has issue on his current hardware, you should still advice Nikon, not Pentax. Because the Nikon are more intuitive to use on that aspect.
you opinion based what? Don't be such a negative factor!
07-10-2016, 02:21 PM   #59
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QuoteOriginally posted by Nicolas06 Quote
it is just easier on a Nikon
I don't know where people get the impression that Nikon's are some sort of magic camera. Good AF tracking performance is not easy with any camera, even Nikon. It's never 'point-and-shoot'.

For proof, have a look at the AF-C shooting guides from Nikon (eg using the D500 for sports events or similar for Canon - eg the Canon 1Dx AF settings guide - 12MB PDF).

Good AF tracking performance requires good camera driving, no matter the brand.
07-10-2016, 02:56 PM   #60
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QuoteOriginally posted by rawr Quote
I don't know where people get the impression that Nikon's are some sort of magic camera. Good AF tracking performance is not easy with any camera, even Nikon. It's never 'point-and-shoot'.

For proof, have a look at the AF-C shooting guides from Nikon (eg using the D500 for sports events or similar for Canon - eg the Canon 1Dx AF settings guide - 12MB PDF).

Good AF tracking performance requires good camera driving, no matter the brand.
Indeed but you need a car that can track on curves and race on strait aways. I think Pentax missed an opportunity to provide that type of engine with a new generation of cameras.
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