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07-24-2016, 09:14 PM - 9 Likes   #1
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Is it possible to autofocus correctly with a Pentax?

Not if you've got a PhD and work for DPR, apparently.


Others have shown cars, bicycles, birds, horses and dogs in action since that regrettable article was published. I posted shots of trail runners the other week with an old K-x and DA55-300 with single spot AF-C.


Now I got the chance to put my Sigma 150-500 onto the K-1, turned on AF-C with simple Auto-33, didn't even use SEL mode - no problems at all at a local flying display, with the planes either on the ground or in the air. I'm a back button focus kinda guy, by the way - just removes one source of user error. The in-flight crops are at 1/800s, f8 and ISO 400.














Last edited by clackers; 07-25-2016 at 03:05 AM.
07-24-2016, 09:43 PM   #2
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Great shots! Pentax equipment may not be the best at AF, but even by modern standards I'd say it gets the job done.

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07-24-2016, 09:58 PM - 7 Likes   #3
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If you were PhD in biology, you'd for sure be an expert in electro optical servo as well (PhD does it all), you'd know that in order to test a Pentax camera your test with aircrafts is not valid, you need to use a DFA70-200 @ f2.8 and a bike at near distance so that the DoF is razor thin (to make sure Pentax fails). Also, you'd have to zoom in your shots at 100% otherwise we can't judge if the shot is tack sharp or not. Now, if you were testing a D5, you'd not use a 70-200 f2.8, you'd use a 300 f4 on distant target (so that DoF is larger), would not zoom photos at 100% and conclude that Woooooooaaaaaaaaaaaaa the D5 AF is the best ever triple gold award you'd give. You'd for sure not consider that the D5 cost three times more than the K1 but evaluate the K1 relative to D5. Anyway, if the K1 would be evaluated as good for AF, it would be a scandal and Nikon would probably cancel their service contract with DPR. For Canon and Nikon, Pentax can't have a decent AF, it is simply not possible, not acceptable.

Best regards.
07-25-2016, 01:56 AM   #4
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@clackers - I reckon you posted pic #2 upside down!

Nice shots - no problems with AF there!

07-25-2016, 02:08 AM   #5
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Nice shots. The colours are outstanding. It's hard to say which I like best. I have no other DSLR to compare with, but I have never found Pentax AF a problem. Pentax makes up for it in other ways.
07-25-2016, 02:43 AM - 1 Like   #6
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Yesterday pictures taken at the local hobby club. No burst shooting !

I also have all my pictures in focus with a Pentax K3 and 60-250mm lens ( also in 100% crop)
Most Made with center focus point, and back button focus.

They do not fly as fast as real aircraft, but make unexpected moves.and are much smaller. Also a helicopter does not fly fast but busy background
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07-25-2016, 03:03 AM - 1 Like   #7
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Can I add that out of courtesy, I asked another shooter who was chimping his Nikon afterwards, "Got some keepers?"

"Unfortunately, no." he replied.

I didn't press him. I know what it's like to be disappointed.

07-25-2016, 03:48 AM - 1 Like   #8
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Excellent Photos Guys

Both of you guys got some great photos here......of course you both know that they are just lucky captures and not the norm for the K1 and K3......!
07-25-2016, 05:07 AM   #9
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QuoteOriginally posted by biz-engineer Quote
If you were PhD in biology, you'd for sure be an expert in electro optical servo as well (PhD does it all), you'd know that in order to test a Pentax camera your test with aircrafts is not valid, you need to use a DFA70-200 @ f2.8 and a bike at near distance so that the DoF is razor thin (to make sure Pentax fails). Also, you'd have to zoom in your shots at 100% otherwise we can't judge if the shot is tack sharp or not. Now, if you were testing a D5, you'd not use a 70-200 f2.8, you'd use a 300 f4 on distant target (so that DoF is larger), would not zoom photos at 100% and conclude that Woooooooaaaaaaaaaaaaa the D5 AF is the best ever triple gold award you'd give. You'd for sure not consider that the D5 cost three times more than the K1 but evaluate the K1 relative to D5. Anyway, if the K1 would be evaluated as good for AF, it would be a scandal and Nikon would probably cancel their service contract with DPR. For Canon and Nikon, Pentax can't have a decent AF, it is simply not possible, not acceptable.

Best regards.
Dude. The test has evolved.
07-25-2016, 05:50 AM   #10
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QuoteOriginally posted by biz-engineer Quote
If you were PhD in biology,
.. you would show your poorly hidden agenda only when confronted with a really objective and scientifc test: You would then simply dismiss all the serious test's results, because it simply did not support your own prejudices.

First: Define the test result. Second: Design clown approach to get to desired results and avoid direct comparisons to more preferred/liked/promoted peer products. Third: call it a "test". Fourth: attack anyone who raises an eyebrow.

QuoteOriginally posted by non relevant PhD:
A fantastic example of how carefully vetted models need to be re-evaluated to make sure they're relevant.
Any photographer actually shooting in the real-world will immediately appreciate how far more accurate Nikon object tracking is vs. Canon.
So, no test is "relevant" if it doesn't prove the writer's personal prejudice/claim of Nikon's superiority. Not Pentax, not Canon.

Remember that is the same PhD owner, who went to any length to call any well reasoned incoming criticism "confirmation bias" and while claiming to have repeated the same poor test over and over again deliberately would not want to quickly run the same test with peer group cameras, even though this would have been logical and easy to do. But now it is clear why this was avoided: It would have shown unwanted results, which are by definition "not relevant".
I thought this approach was only taught in North Korea and some backward kingdoms these days.
Credibility? Professionalism? Robustness? Scientific approaches? Ah, get away with that. Evolve it until it fits.

Did somebody ever wonder if there is a correlation between the actual qualification of people with PhDs and them working as paid lowly marketing/writers/bloggers versus working in an actual scientific job in their home topic?
I bet it is only the very best medical doctors who drive taxi cabs / write blogs and all the failed low quality ones end up paid very well in hospitals/university/large pharma companies etc. Or, wait? Hm. Maybe something got mixed up here.
07-25-2016, 06:13 AM - 1 Like   #11
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No offense meant to anyone on this thread, but aren't we kinda dragging this autofocus review anger out just a tad? If others using different brand came to this site (and i am sure they do) is this what we would want them to find? Especially if these folks are looking to switch to pentax?

Of course showing the capabilities of the camera is great, especially when there are detractors who say it can't or won't do something, but perhaps we may want to tone down some of the verbiage. Bashing other sites makes us just as bad as them.

If we did tone it down just a bit, we may just be able to avoid being the butt of people's jokes, i.e. the camera stores playful (and pretty funny) warning preceding their review of the K-1.
07-25-2016, 06:18 AM   #12
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What's a DPR?
07-25-2016, 06:56 AM - 3 Likes   #13
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Not too shabby, but propeller planes aren't terribly fast.

I performed my own AF test this weekend, k5iis, DA*300, AF-C, Centre Point, Back button. My target was an experimental high-speed Dutch watercraft. Its speed is written on the side, but I think they were being modest. It was closer to Mach III in reality.

I propose all future AF tests use this watercraft as a test subject if they have any hope of remaining objective.

07-25-2016, 07:29 AM   #14
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Interesting conversation so far. But having owned the K-X and the 55-300 for quite a while now (including K-5ii and s) I can say that K-X and 55-300 DA L that came with it is indeed a faster focusing system. Has anybody every bothered noticing it?
And no K-5ii and 55-300 isn't faster. K-X and 55-300 is and is way more responsive than the K-5ii combination. Its like K-X and that 55-300 DA L are married to do the job well.
07-25-2016, 01:38 PM   #15
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I guarantee you , DRP are not pushing Nikon, no no no, this article https://www.dpreview.com/news/1419516967/nikon-d500-versus-d750-which-one-is-right-for-you was only a random idea. Could have been "K3 versus K1, which one is right for you", but no no no , it's only luck that decided to do an article for Nikon LoL . I'm just wondering if camera performance actually lies in the amount of money paid to magazines and online review sites.
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