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07-06-2012, 07:14 AM   #16
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QuoteOriginally posted by JinDesu Quote
AF.A let's the camera decide between AF.C and AF.S. AF.C is continuous autofocus while shooting. AF.S is single shot autofocus.

He was moving his center point AF to other points on his grid - the camera will lock AF onto wherever he set that point to.

This feature says - if you lock onto a target with the center point, it will set an "area" around that point in pink. That area allows the camera to continue to focus on the subject IF that subject moves from the center point to any of those points in pink. Basically it's great for taking pictures of any subject that may move - the camera will make sure to keep them in focus as long as they don't exit the pink points.
OK, that seems like a useful feature for birding then.

I am hoping this will be similarly implemented in the next version of their flagship camera.

Thanks for the reply.

JP

07-06-2012, 07:45 AM   #17
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A large segment of Pentax users will find this useful feature alien to them because they have been too ingrained to shoot using the center AF point only.
07-06-2012, 07:52 AM   #18
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QuoteOriginally posted by creampuff Quote
A large segment of Pentax users will find this useful feature alien to them because they have been too ingrained to shoot using the center AF point only.
I'll have to see how well it is implemented. It sounds like something I would leave active on my camera all the time.
07-06-2012, 08:01 AM   #19
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Canon users have long appreciated AF point expansion. With Pentax now offering this option, and with significant general improvements in AF performance, Pentax may well be the budget choice for sports photographers. I hope to see this taken further in the next Pentax flagship...

--DragonLord

07-06-2012, 08:11 AM   #20
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This looks just GREAT. You can choose area where your af.s is working. Good for framing and shooting. This looks really good!
07-06-2012, 10:32 AM - 1 Like   #21
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OK, so let me see if I understand.

On my K-x if I am shooting BIF I use 5 point AF. As I track the bird on AF-C, if it moves from the centre point to one above or below or to the side, the camera uses that point for focus. If the BIF is isolated, besides faster AF, this may be the same thing?

The difference may shooting sports? In football, on my K-x, if I use 5 point AF, the camera will focus on what it chooses to. On the K-30, if I use centre point and expanded AF, if *I* choose it to focus on a player, it will continue to track THAT player as it moves outside the centre focus point?

What if the player moves slightly behind another player? I wonder if the K-30 will then focus on the closer player?
07-06-2012, 11:54 AM   #22
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QuoteOriginally posted by creampuff Quote
A large segment of Pentax users will find this useful feature alien to them because they have been too ingrained to shoot using the center AF point only.
I can relate to that !

JP
07-06-2012, 11:56 AM   #23
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QuoteOriginally posted by gebco Quote
OK, so let me see if I understand.

On my K-x if I am shooting BIF I use 5 point AF. As I track the bird on AF-C, if it moves from the centre point to one above or below or to the side, the camera uses that point for focus. If the BIF is isolated, besides faster AF, this may be the same thing?

The difference may shooting sports? In football, on my K-x, if I use 5 point AF, the camera will focus on what it chooses to. On the K-30, if I use centre point and expanded AF, if *I* choose it to focus on a player, it will continue to track THAT player as it moves outside the centre focus point?

What if the player moves slightly behind another player? I wonder if the K-30 will then focus on the closer player?
Good post ! +1

I am looking forward to some details on that.

JP

07-06-2012, 12:04 PM   #24
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Unless another user posts with results, I will be going to B&H on Sunday to play with the K-30, and I will let you guys know how this works in practice with the camera.
07-06-2012, 12:10 PM   #25
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QuoteOriginally posted by rawr Quote
However if you are shooting a subject like a footballer running left to right across a big football field with movement across a wider plane plus variations in distance from the camera, or a footballer running towards the camera from far to near, then this new feature comes into it's element.
I think the big news is that Pentax is in the tracking ball game, no matter what the results at this point, they are working on it. And for it first to appear on an entry level or mid level camera shows their committment to it.

As to your interesting question, how does any camera track an object moving through the frame. I would think it would be by a unique pattern of pixels at the focus point. So if one's camera focused on the arm of a person, the camera would continue to track that pattern until it disappeared or changed - at which point the camera will freeze . And this tracking might occur while the camera is snapping off 7 fps. Boggles my mind. I suppose that Pentax had to really upgrade the processing power in the K30.
07-06-2012, 12:31 PM   #26
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QuoteOriginally posted by gebco Quote
What if the player moves slightly behind another player? I wonder if the K-30 will then focus on the closer player?
In that case, the K-30 temporarily converts its focus lamp into a stun ray, dropping the player in front to his knees, and then resumes focusing on the target player.
07-06-2012, 12:41 PM   #27
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QuoteOriginally posted by gebco Quote
What if the player moves slightly behind another player? I wonder if the K-30 will then focus on the closer player?
It's possible that the K-30's AF algorithms have been tuned to be less likely to be distracted by obstructions. My K-5 would immediately refocus on the closer player in such a situation, but let's hope the K-30 is smart enough not to be distracted by this situation.

The flagship Canon and Nikon DSLR cameras can be set to ignore obstructions or refocus immediately, with an adjustable level of sensitivity to obstructions. Accurately detecting such a situation needs highly intelligent AF algorithms as well as many more AF points than 11. Pentax has certainly made at least some level of progress with the AF algorithms, but let's hope the next flagship has more AF points...

--DragonLord

Last edited by bwDraco; 07-06-2012 at 12:47 PM.
07-06-2012, 03:14 PM   #28
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QuoteOriginally posted by DragonLord Quote
Accurately detecting such a situation needs highly intelligent AF algorithms as well as many more AF points than 11.
When you get into predictive tracking, you probably need more than just additional AF points and smart algorithms.

If you look at (for example Nikon) they also throw in a RGB colour sensor in the AF system to (theoretically) provide the AF with more information to help it make decisions about moving target objects and background or non-target objects - eg the white jersey of a football player against the green grass in the background or the red jerseys of the opposing team. The hardware starts to get complicated the smarter you want the AF to be. It can also start to eat up a lot more CPU cycles, which is why you see the big sports shooter DSLRs like the Canon 1D X feature a CPU dedicated just to the AF.
07-06-2012, 05:37 PM   #29
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I have upped some sample shots using this feature, set for central focus point.

https://www.pentaxforums.com/forums/pentax-k-30/191668-k-30-expanded-auto-foc...ng-magpie.html
07-06-2012, 09:30 PM   #30
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Anyone tried this with a MACRO lens? might be handy tracking insects that move slightly...
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