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07-05-2012, 07:30 PM   #1
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K-30 Expanded Area AF


Only a small clip of this new feature, none of it in use unfortunately - I will try later today if possible. Described as:

"A new expanded area AF function allows the sensor module to continue to track a moving subject in AF select mode, even when it moves out of a pre-assigned auto-tracking area, by assessing distance data collected by neighboring focus sensors. This greatly improves the accuracy and speed of detecting moving subjects during autofocus shooting, and autofocusing performance when using a telephoto lens."

And in the manual as:

When Expanded Area AF is enabled, if your subject briefly moves out from the focus point that was selected when the focus mode was set to AF.C (or when AF.A was enabled), the camera will continue to focus on your subject based on information from the focus points (back-up focus points) surrounding the selected focus point. The back-up focus points are displayed in pink on the status screen.

07-05-2012, 07:32 PM   #2
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Damn, that's good to know!
07-05-2012, 07:49 PM - 1 Like   #3
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...I feel hard to understand anyway......
07-05-2012, 07:49 PM   #4
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QuoteOriginally posted by FruitLooPs Quote
Pentax K-30 Expanded AF Fuction - YouTube

Only a small clip of this new feature, none of it in use unfortunately - I will try later today if possible. Described as:

"A new expanded area AF function allows the sensor module to continue to track a moving subject in AF select mode, even when it moves out of a pre-assigned auto-tracking area, by assessing distance data collected by neighboring focus sensors. This greatly improves the accuracy and speed of detecting moving subjects during autofocus shooting, and autofocusing performance when using a telephoto lens."

And in the manual as:

When Expanded Area AF is enabled, if your subject briefly moves out from the focus point that was selected when the focus mode was set to AF.C (or when AF.A was enabled), the camera will continue to focus on your subject based on information from the focus points (back-up focus points) surrounding the selected focus point. The back-up focus points are displayed in pink on the status screen.
I don't have a K30 but this is interesting and, sorry for the K30 newbie questions.
First, what is "AF.A" ?
Then, once you "select" the focus point, what exactly are you doing when pressing on the 4-way pad and thus changing the "look" of the focus points ( the grid) ?

Just curious how this thing works and hopefully will be a feature of the future K5 "replacement" ... perhaps a good thing?

Cheers.

JP

07-05-2012, 07:59 PM   #5
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QuoteOriginally posted by jpzk Quote
I don't have a K30 but this is interesting and, sorry for the K30 newbie questions.
First, what is "AF.A" ?
Then, once you "select" the focus point, what exactly are you doing when pressing on the 4-way pad and thus changing the "look" of the focus points ( the grid) ?

Just curious how this thing works and hopefully will be a feature of the future K5 "replacement" ... perhaps a good thing?

Cheers.

JP
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.
07-05-2012, 08:05 PM   #6
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I've tried this on a K30, It's a very useful feature when taking bird (on a branch) photos. If the bird is moving around but still inside the viewfinder, you don't need to shift focusing point, the camera would do that for you automatically.
07-05-2012, 08:24 PM   #7
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QuoteOriginally posted by JinDesu Quote
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.
I hope I'm simply misunderstanding this function (based on how the menu is being adjusted in the video), but I get the impression that you will be required to know in advance which direction your subject intends to move. What if you are predicting that the subject will move to the right, but then he/she/it "unexpectedly" moves to the left? Aside from automobiles and a few other things, we can very rarely predict which direction our subjects may move; yet this feature appears to expect us to know in advance.

Am I misunderstanding this?

Or is it possible to set more than one of the "focus areas" to work at the same time? And, if it is possible, then why not have a "one-click-sets-all" option?
07-05-2012, 08:27 PM   #8
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QuoteOriginally posted by Welfl Quote
I hope I'm simply misunderstanding this function (based on how the menu is being adjusted in the video), but I get the impression that you will be required to know in advance which direction your subject intends to move. What if you are predicting that the subject will move to the right, but then he/she/it "unexpectedly" moves to the left? Aside from automobiles and a few other things, we can very rarely predict which direction our subjects may move; yet this feature appears to expect us to know in advance.

Am I misunderstanding this?

Or is it possible to set more than one of "focus areas" to work at the same time? And, if it is possible, then why not have a "one-click-sets-all" option?
You set the AF point you want (let's say center).

The 9 points AROUND that center point are now the pink points - and will allow the camera to focus on the subject if the subject moves into that area. The main use of this function is when you have the subject focused, and the subject decides to move as you are shooting.

I imagine for the camera to figure out the focus after more than 1 set of points away may be a bit hard.

07-05-2012, 08:35 PM   #9
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QuoteOriginally posted by JinDesu Quote
You set the AF point you want (let's say center).

The 9 points AROUND that center point are now the pink points - and will allow the camera to focus on the subject if the subject moves into that area.
Okay, I think that clarifies it for me. It depends on whether you actually mean "if the subject moves into any one of those areas." Right?

QuoteOriginally posted by JinDesu Quote
The main use of this function is when you have the subject focused, and the subject decides to move as you are shooting.
Yes, that I understood.

QuoteOriginally posted by JinDesu Quote
I imagine for the camera to figure out the focus after more than 1 set of points away may be a bit hard.
I don't really understand what you mean in that sentence, but that's probably mostly because my own confusion and very subjective wording may have misled you.

Thank you for your answer. I appreciate it.
07-05-2012, 08:40 PM   #10
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QuoteOriginally posted by Welfl Quote
Okay, I think that clarifies it for me. It depends on whether you actually mean "if the subject moves into any one of those areas." Right?
As Frank stated above - it's great for taking pictures of moving subjects like birds. You aim at the bird, lock focus, and if the bird moves around, the camera will continue to focus on it - until the bird leaves the pink points. But as long as the bird moves into any of the pink points, the AF works.


QuoteQuote:
I don't really understand what you mean in that sentence, but that's probably mostly because my own confusion and very subjective wording may have misled you.

Thank you for your answer. I appreciate it.
I assume the camera figures out what object it is focused on and tracks it up to one AF point away. For the camera to figure out if it moves more than one AF point away, it might need a lot of processing power (guessing here).

So that's probably why there isn't a "One click set's all" solution.
07-05-2012, 09:03 PM   #11
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QuoteOriginally posted by JinDesu Quote
You aim at the bird, lock focus, and if the bird moves around, the camera will continue to focus on it - until the bird leaves the pink points. But as long as the bird moves into any of the pink points, the AF works.
I promise I'm not trying to be intentionally obtuse or dense here, and I appreciate your patience with me: So if I click the shutter while the bird is in the frame but is between two of those pink points, it won't be in focus? In other words, does the bird actually have to be precisely on one of the pink points (or vice versa) for this type of focusing to work? Or is there no such thing as "between" the pink points? By that, I mean are they all contiguous? It's actually hard for me to tell as I watch the video (probably because I've never used any DSLR before; everything I've learned for the past year and a half as been by doing research on the internet).

QuoteOriginally posted by JinDesu Quote
I assume the camera figures out what object it is focused on and tracks it up to one AF point away. For the camera to figure out if it moves more than one AF point away, it might need a lot of processing power (guessing here).

So that's probably why there isn't a "One click set's all" solution.
Your answer confirms that my phraseology and lack of understanding was confusing you. When you answered with, "...as long as the bird moves into any of the pink points, the AF works," it tells me that they are all functioning at the same time. In essence, that's what I meant by "one-click-sets-all."

However, this leads me back my initial point of confusion: Why, then, is there a menu that lets you "move around" between the different areas of the frame separately (right, left, top, bottom, corners) -- as FruitLooPs is showing us in the video? What's the point of being able to move around from one to the other individually if they all function at the same time? That's what misled me to believe you could only set one "pink" area at a time.

Last edited by Welfl; 07-05-2012 at 09:23 PM.
07-05-2012, 09:35 PM - 1 Like   #12
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This sounds like a step in the right direction for Pentax AF.
07-05-2012, 11:48 PM   #13
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Yeah, but...but...but, it sounds like one has to be using the center focus point for the subject; for there to be a layer of pink focus points all around the subject point.

Its definitely a step in the right direction, but Pentax really needs more focus points than 11 to really impress. Perhaps we'll see more focus points in the K5 successor with this functionality from the K30.
07-06-2012, 03:37 AM   #14
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The 'bird on a branch' is possibly a bad example for this feature. If the bird is originally in focus and only moves left - to - right a small distance and stays the same distance from the camera it's likely to remain in focus no matter what. Especially if you provide adequate DOF.

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.
07-06-2012, 04:05 AM   #15
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Interesting future for sports maybe?
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