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05-12-2015, 10:04 AM   #646
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QuoteOriginally posted by derekkite Quote
With all this stuff you have to start with the realization that 75% of the photos ever taken can be captured with almost any camera ever made. What makes technological improvements important are the 25%. It was possible to get stunning wildlife shots with film, but it took a container full of film, a couple helpers loading bodies, and a staffed lab somewhere to process them all. A huge pile of money helped. That is what National Geographic did, and did well. Now with a $1k or less body and that much again on a lens you can get stunning shots.

That canon with the low DR and small number of points are good for 95% of the photos taken.

So this is what I face to get a decent wildlife shot. This is an uncropped unprocessed shot of an osprey nest yesterday morning. I am unusually close to the nest, very seldom am I able to get that close, and the male will land on a post half the distance away. If I told you where it is I would have to shoot you. 500mm sigma 4.5 lens on a k3

On the K3 the focus point is about the size of the head of the bird. I am able to get good reliable focus. The K5 would span the shoulders and part of the other bird, and there were lots of throwaways as a result. The canon would have the same problem.

At twice the distance, the point is too big. I would like a point half the size, I miss shots on things further away. But, and a large but, a smaller focus point means that the slightest movement changes focus, either me handheld trying to keep the thing steady, or the subject moving. So it is necessary to add points and logic to help the photographer get good shots. In my shooting yesterday morning with these birds flying around I had maybe 25% keeper rate. There will never be 100%, but every marginal improvement in hardware capabilities gives me more keepers. I shot manual focus 400mm for a year and got birds in flight. About 1 in 600 shots. The K5 with 150-500 sigma was quite a bit better, but maybe 10% or slightly less were ok.

For a smaller point to give me more keepers requires that there be points surrounding it. Right now on the K3 a flying osprey can disappear between points, which I think causes loss of focus. So smaller points, tightly spaced gives enough to the logic to keep focus. Yes we are talking tracking, but with small focus points tracking is a necessity in a busy dynamic scene.

In all these discussions it is easy think that what we have works. What I have found is that I limit my shots to scenes and situations where I know I can get results. If you have a lens that flares, do you take shots into the sun? No way, it is a waste. But if you have a nice 15mm limited, that is all you end up doing because the results are amazing. Same with focus. A fast moving subject in a busy scene usually means I don't lift the camera because I won't get a shot anyways. If my body and lens were quick enough, had a very large number of points and a fast processing engine to implement very good logic, I would take those shots.

The K3 is pretty good with focus, it has rudimentary tracking ability. Some improvements with faster lenses and some optimizations of the logic are possible, and I think the K3II will maximize it's capability. To improve requires more points more logic capability, more speed. That will be in the next major update of the aps-c.
derekkite, thanks for your thoughtful analysis of the various focus issues that challenge your needs, whether they be additional focus points, larger or smaller and the necessity of improved tracking speed with the smaller points. For the first time I finally understand the issues from a logical perspective.

05-13-2015, 01:00 AM   #647
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QuoteOriginally posted by monochrome Quote
You have no basis to make that statement. In a few months there will have been enough new lenses and enough K-3II's tested in the wild by both biased and disinterested parties to begin to make qualified statements. Until then anything such as this is at best ill-advised speculation or at worst intentional spreading of FUD.

It is also a straw man argument, since Pentax makes no claims to be a sports/action camera brand. The claim is to be a field camera, with emerging attempts to break into the professional wedding space - but you probably know that.

These statements get indexed quite high on Google searches because of the clicks received on PF - as I suspect you fully understand.
As I said again I don't care for my practice, a body like K3 is good enough AF I think. Now as if Pentax has Canikon performance for AF I remember AF test where Nikon D7100 as 97% in focus pictures, K5 arround 50% and K3 arround 60-70%... You can also quote Kenspo that said several time that Pentax AF is behind, that Pentax is aware and they improve.

It is the realitly. If ultimate AF is critical, Pentax is not the same level. It will work sure, but you'll pay more or the same for less. As if Pentax is after this or not, please explain then the 150-450 and all the guys after wildlife photography, birds and with super high expectation on AF?

I'am for Pentax, I like their historical compromize of small/light and high quality lenses, I like the WR and in body SR. I like the fact they extend to more professionnal lenses and a FF body and there lot of enthousiasm.

If somebody is after action/sport/wildife and ask himself what brand to choose and does a search on google, I have the impression it is more fair he see some people showing concern on AF and speak of more reasonnable expectations on this topic for Pentax brand than to say it is perfect based on 2 future lenses (one being said hit and miss for AF by 1 reviewer) and a body that is not even sold neither.

With all our enthousiasm for Pentax the safe bet on ultimate AF is still not Pentax... This might change in 3-4 years when several body and more than 2 lenses are said to have fast AF in the echosystem. In term of price too this is not still the same, a D7100 with a sigma perform very well. Many Canon L even at f/4 perform also very well for AF. Pentax has just 2 very expensive lenses not fully tested.

This improve, this is necessary for some practices and for Pentax to be fully recognized and I think we are all aware of that too. We can like it or not, it is not 27AF system we have today that will solve all issues.
05-13-2015, 02:52 AM - 2 Likes   #648
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QuoteOriginally posted by Nicolas06 Quote
As I said again I don't care for my practice, a body like K3 is good enough AF I think. Now as if Pentax has Canikon performance for AF I remember AF test where Nikon D7100 as 97% in focus pictures, K5 arround 50% and K3 arround 60-70%... You can also quote Kenspo that said several time that Pentax AF is behind, that Pentax is aware and they improve.

It is the realitly. If ultimate AF is critical, Pentax is not the same level. It will work sure, but you'll pay more or the same for less. As if Pentax is after this or not, please explain then the 150-450 and all the guys after wildlife photography, birds and with super high expectation on AF?

I'am for Pentax, I like their historical compromize of small/light and high quality lenses, I like the WR and in body SR. I like the fact they extend to more professionnal lenses and a FF body and there lot of enthousiasm.

If somebody is after action/sport/wildife and ask himself what brand to choose and does a search on google, I have the impression it is more fair he see some people showing concern on AF and speak of more reasonnable expectations on this topic for Pentax brand than to say it is perfect based on 2 future lenses (one being said hit and miss for AF by 1 reviewer) and a body that is not even sold neither.

With all our enthousiasm for Pentax the safe bet on ultimate AF is still not Pentax... This might change in 3-4 years when several body and more than 2 lenses are said to have fast AF in the echosystem. In term of price too this is not still the same, a D7100 with a sigma perform very well. Many Canon L even at f/4 perform also very well for AF. Pentax has just 2 very expensive lenses not fully tested.

This improve, this is necessary for some practices and for Pentax to be fully recognized and I think we are all aware of that too. We can like it or not, it is not 27AF system we have today that will solve all issues.
Nicolas, whatever, still it seems that you are just perpetuating hearsay and cementing prejudices. There are almost no reliable tests for the AF, be it CAF or SAF and if there are any the results come to a surprise. Here one of the K-5 from 2011 in a German photomagazine: http://www.colorfoto.de/testbericht/7/7/6/2/0/2/Test_Autofokus_ColorFoto_2011-09.pdf
The K-5 seems to have the highest rate of sharp images amongst its peers, as you can see by the graphics, even if you can't read German.
Now, I am sure there might be differences and different experiences in different envbironments but you definitely are close to just spreading FUD and I think you are aware that such postings just get high rankings in search engines and contribute to the myth which again will be used in another posting without proper backing of the claims. It's the internet - who do I try to explain that, you all know how this works.
05-13-2015, 03:12 AM   #649
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QuoteOriginally posted by monochrome Quote
The Canon EOS 6D is a full-frame 20.2MP DSLR
What? No built-in flash? Who would buy it?

05-13-2015, 03:45 AM   #650
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QuoteOriginally posted by Not a Number Quote
What? No built-in flash? Who would buy it?
I won't buy the 6D. I'm buying a K-3II as soon as the money gets in. (And still no built-in flash ssshhhhhhh).
05-13-2015, 03:50 AM - 1 Like   #651
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Maybe, if K-5 is used with a manual focus lens, and the user it's not seeing well, the keeper rate could be 50% or less. But I had K-5, and with AF lenses, the keeper rate is much higher, nowhere near 50%. With all due respect Nicolas06, I am curious , where did you find that 50% data? Anyway, this number is totally wrong. Or, maybe with a broken camera.
05-13-2015, 04:45 AM   #652
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Available to pre-order in Australia from the Pentax webstore.

https://www.pentax.com.au/product/k-3-ii-pre-order Body Only $1,349.00
https://www.pentax.com.au/product/k-3ii-16-85-kit-pre-order $2,099.00
https://www.pentax.com.au/product/pentax-k-3-ii-da-18-135mm-wr-pre-order $1,799.00
05-13-2015, 05:00 AM   #653
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QuoteOriginally posted by JimmyDranox Quote
Maybe, if K-5 is used with a manual focus lens, and the user it's not seeing well, the keeper rate could be 50% or less. But I had K-5, and with AF lenses, the keeper rate is much higher, nowhere near 50%. With all due respect Nicolas06, I am curious , where did you find that 50% data? Anyway, this number is totally wrong. Or, maybe with a broken camera.
I guess it's from here:
Pentax K-3 Review - Autofocus | PentaxForums.com Reviews
But I'm not surprised that you can get significantly better results. That's what usually happens when you are using, instead of testing a camera

05-13-2015, 06:23 AM   #654
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QuoteOriginally posted by Kunzite Quote
I guess it's from here:
Pentax K-3 Review - Autofocus | PentaxForums.com Reviews
But I'm not surprised that you can get significantly better results. That's what usually happens when you are using, instead of testing a camera
Not just there, but numerous other sites on the net and threads here especially concerning the K5. My K5 got a Katzeye screen and does duty exclusively for longer manual lenses. The K5 for more recent comments and the K10d seem to be the source of a lot of the reputation.

I was pleasantly surprised with the K5II and am even more pleased with the K3. Even so, when I go birding, I do notice that my Canon friends have a lot higher AF success rate with BIF than I do on the K3. A good part of that is on me, but it seems pretty consistent.
05-13-2015, 02:21 PM   #655
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AF and Sensor Pixel Performance

Hi,

Below are statements that are found at the web address below them (one someone was referring to before me). It states that the K3 in a test focuses in 1.4 seconds as opposed to the K5 IIs that focuses at 2.1 seconds in the test. I have a K5 IIs and have never had a K-3 series camera. The K5 IIs performs very well for me with my Sigma 150-500 when shooting birds in flight and with stills. In reference to the K-3 I have seen reviews that find the K5 IIs with a slightly better rating (example, DXOMark). Also, the K-3 seems to use more power per reviews that I have seen, which may not be a bad thing since maybe the focus activity is where some of that is going if it is in fact faster. An important feature to me that would be significant would be an AF faster than the K3, in the K3II or its successor (aps-c). That would be one of the key features I would look for in weighing a possible upgrade. Effective AF during tracking and for stills is what I would be looking for. Also a sensor that utilizes its pixels in a way that creates an excellent IQ without any more noise than its predecessors.


Camera
Time to Focus
K-3 1.4s
K-5 IIs 2.1s


Read more at: Pentax K-3 Review - Autofocus | PentaxForums.com Reviews
05-13-2015, 02:51 PM - 1 Like   #656
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QuoteOriginally posted by Nicolas06 Quote
As I said again I don't care for my practice, a body like K3 is good enough AF I think. Now as if Pentax has Canikon performance for AF I remember AF test where Nikon D7100 as 97% in focus pictures, K5 arround 50% and K3 arround 60-70%... You can also quote Kenspo that said several time that Pentax AF is behind, that Pentax is aware and they improve.
You are refering to the PF review of the K3, you forget to mention that the K3 AF was tested with the DA* 60-240 f4 (a lens not known for its AF speed) against the Nikon D7100 and 70-200 f2.8. I'm no engineer but as tested these two systems are far from equal. Wait for the D-FA* 70-200 and we'll see how well the K3 (and K3ii) AF really performs. (we can then compare it to Nikon and Canon at will)
I gave my K3 + -F 135 f2.8 (a lens which you own) to a photographer friend of mine, a Canon users who shoots with 135/f2 L glass and he was dumbfounded by the AF performance of the combo, (and IQ of the little guy).
05-14-2015, 12:00 PM   #657
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QuoteOriginally posted by Stavri Quote
You are refering to the PF review of the K3, you forget to mention that the K3 AF was tested with the DA* 60-240 f4 (a lens not known for its AF speed) against the Nikon D7100 and 70-200 f2.8. I'm no engineer but as tested these two systems are far from equal. Wait for the D-FA* 70-200 and we'll see how well the K3 (and K3ii) AF really performs. (we can then compare it to Nikon and Canon at will)
I gave my K3 + -F 135 f2.8 (a lens which you own) to a photographer friend of mine, a Canon users who shoots with 135/f2 L glass and he was dumbfounded by the AF performance of the combo, (and IQ of the little guy).
The kind of test done by PF doesn't need a particular fast lense, it require predictive AF. This is what apparently they started to add in K3-II. K3 added the necessary hardware and some color tracking. K3-II add the software for improving predictive AF when the subject come toward the photographer (as explained by Pentax themselve). But as this is the first iteration while it should improve, it would be strange if it performed at well on first try as Nikon's own implementation that has been refined for many years and bodies iterations.

I think really Pentax/Ricoh is in the process of fixing AF. For many (me included) something like the K3 is enough. For thoses not doing shallow deph of field or relying on manual focus, K5 is enough. For thoses after action/sport that need more, we start to see the first lenses and first bodies to use the necessary technology. It will require a few models/years/iteration through to be as refined as it is on Canikon. This is common sence. So yes the new lenses on K3-II will improve. What? Maybe 80 or 85% success rate on the same test?

The second generation of FF or the body after K3-II with the real wave of related innovation should be almost as good and the generation after should be as good (or better) than Canikon if Pentax continue on the topic.

Last edited by Nicolas06; 05-14-2015 at 12:10 PM.
05-14-2015, 12:07 PM   #658
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QuoteOriginally posted by JimmyDranox Quote
Maybe, if K-5 is used with a manual focus lens, and the user it's not seeing well, the keeper rate could be 50% or less. But I had K-5, and with AF lenses, the keeper rate is much higher, nowhere near 50%. With all due respect Nicolas06, I am curious , where did you find that 50% data? Anyway, this number is totally wrong. Or, maybe with a broken camera.
You have your response from other forumers. Of course such keeper rate is not from wide angle lenses set at hyperfocal distances but more an action/sport scenario.

But use your K5 AF with a 85mm f/1.4 in a pub wide open for a tight portrait without using MF to correct it and your keeper right might be well bellow 50%. The K5-II fixed the issue of focussing in dim light and the K3 fixed the issue of targetting a precise area of the image thanks to smaller AF points. So the issue is solved with K3.

K3 implemented a basic tracking through the metering sensor but not yet predictive AF. From Pentax description it seems they now added some predictive AF in K3-II... Let them the time to refine their algorithms and you'll have the issue entirely solved.
05-14-2015, 12:11 PM   #659
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I believe a Pentax executive stated they intend for Pentax to be THE BEST auto-focus, not merely competitive (understanding that will be a work-in-progress).

We all REALLY need to learn to think about each camera body as a step on a journey - an iteration, as you have correctly stated - and stop looking at each camera body as a bucket.
QuoteOriginally posted by Nicolas06 Quote
The kind of test done by PF doesn't need a particular fast lense, it require predictive AF. This is what apparently they started to add in K3-II. K3 added the necessary hardware and some color tracking. K3-II add the software for improving predictive AF when the subject come toward the photographer (as explained by Pentax themselve). But as this is the first iteration while it should improve, it would be strange if it performed at well on first try as Nikon's own implementation that has been refined for many years and bodies iterations.

I think really Pentax/Ricoh is in the process of fixing AF. For many (me included) something like the K3 is enough. For thoses not doing shallow deph of field or relying on manual focus, K5 is enough. For thoses after action/sport that need more, we start to see the first lenses and first bodies to use the necessary technology. It will require a few models/years/iteration through to be as refined as it is on Canikon. This is common sence. So yes the new lenses on K3-II will improve. What? Maybe 80 or 85% success rate on the same test?

The second generation of FF or the body after K3-II with the real wave of related innovation should be almost as good and the generation after should be as good (or better) if Pentax continue on the topic.
QuoteOriginally posted by Nicolas06 Quote
You have your response from other forumers. Of course such keeper rate is not from wide angle lenses set at hyperfocal distances but more an action/sport scenario.

But use your K5 AF with a 85mm f/1.4 in a pub wide open for a tight portrait without using MF to correct it and your keeper right might be well bellow 50%. The K5-II fixed the issue of focussing in dim light and the K3 fixed the issue of targetting a precise area of the image than to more and more importantly smaller AF points.

As I said in a previous post, K3 is in the process of fixing AF. They made huge progress, they continue but they'll need a bit more time to have it perfect.
05-14-2015, 12:42 PM   #660
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QuoteOriginally posted by Stavri Quote
You are refering to the PF review of the K3, you forget to mention that the K3 AF was tested with the DA* 60-240 f4 (a lens not known for its AF speed) against the Nikon D7100 and 70-200 f2.8. I'm no engineer but as tested these two systems are far from equal. Wait for the D-FA* 70-200 and we'll see how well the K3 (and K3ii) AF really performs. (we can then compare it to Nikon and Canon at will)
I gave my K3 + -F 135 f2.8 (a lens which you own) to a photographer friend of mine, a Canon users who shoots with 135/f2 L glass and he was dumbfounded by the AF performance of the combo, (and IQ of the little guy).
It is really fast, that's true but I tend to think that my (now sold) 50-135 that is slow to focus tend to be more precise and a bit sharper overall than my F135. It accept more crop for example. The 50-135 was unable to do any sport with the K5 through and I think the F135 could have handled it. It is better to not have the focus perfect than to be totally off because the lense is too slow.

The F135 can be quite sharp, maybe its me but with it I require a bit more shoots to be covered and also the lense has more optical issues (more CA, a bit less contrasty, you really benefit from closing at least to f/5.6).

But don't get me wrong, the rendering is really really nice and I quite enjoy the lense. I prefer the F135 overall but it may be more due to size than ultimate quality or ultimate AF.
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