[schnur07]

Sorry for the stupid question, but I'm trying to understand the autofocus settings in the menu (AF Active Area) vs the settings that can be changed by the AF Mode button.

For example, what's the difference if I have the AF Active Area set on "auto 27" and the AF Mode on "Spot" vs AF Active Area set on "Spot" (single dot icon) and AF Mode on "Spot"?

I have read the menu and I can't figure it out. Maybe because it's too late in the evening after a long work day...

[Adam]

There are two general sets of settings- the active area, which is the AF points used (27, spot/select, or somewhere in between) and the AF mode (either single, continuous, or auto). Spot only refers to the former. Usually you'll be in single AF (AF.S) unless you're shooting something that's moving.

[microlight]

The AF systems are very similar between the KP and the K-3II (same SAFOX 11 system) except that the AF button does double duty on the KP where there’s a dedicated button on the K-3II.

I tend to use AF.C pretty much exclusively on the K-3II because using back-button focus (disabling the shutter button AF activation), as well as AF.C it’s possible to focus with a dab on the AF button and then release, mimicking AF.S. (Never used AF.A.)

Another benefit of AF.C is linked to the AF points themselves. You can use just the centre point as in AF.S: many people do. However there’s additional functionality using the 27 points. In the auto mode, the camera selects what it wants to focus on - this was true right back to my *istDS. But in the select mode in AF.C (I use the centre square of 25 cross-type points), if you activate AF with the subject under the centre red square and continue to hold the AF button then the AF will track the subject across the focus points. Not perfect, not predictive but better than many think.

[timb64]

The AF systems are very similar between the KP and the K-3II (same SAFOX 11 system) except that the AF button does double duty on the KP where there’s a dedicated button on the K-3II.

I tend to use AF.C pretty much exclusively on the K-3II because using back-button focus (disabling the shutter button AF activation), as well as AF.C it’s possible to focus with a dab on the AF button and then release, mimicking AF.S. (Never used AF.A.)

Another benefit of AF.C is linked to the AF points themselves. You can use just the centre point as in AF.S: many people do. However there’s additional functionality using the 27 points. In the auto mode, the camera selects what it wants to focus on - this was true right back to my *istDS. But in the select mode in AF.C (I use the centre square of 25 cross-type points), if you activate AF with the subject under the centre red square and continue to hold the AF button then the AF will track the subject across the focus points. Not perfect, not predictive but better than many think.

The problem I’ve found with that method is that sometimes the camera will pick the wrong item to focus on, particularly if it is a small bird in a tree,the camera will choose a nearby twig.I find myself switching between 25 points and Centre Spot to overcome this but neither is “perfect”.

I’ve only had my KP for about four months so I’ll admit I’m still very much in the learning/experimentation stage.

[microlight]

Hi Tim,

Yup, not perfect, doesn’t do well in all circumstances. With teles, some of it is down to getting the right object under the centre point when AF is initiated - difficult with lenses that can tend to waggle about.

Edit: I forgot to mention the 'hold AF status' in the custom menus (no. 18 in the K-3II). If it's off, which is my default, then it will re-focus immediately if your object goes behind another object, for example a bird going behind a branch. Setting this to low, medium or high will tell the camera to delay re-focusing, the length of which depending on the setting. I don't bird much, so mine's off, but you might want to experiment with the other settings - might help.

My biggest problem with AF on the KP is that I sometimes hit the switch on the side of the camera's front by accident, physically commanding the camera to go into MF mode. And, not realizing I've done it, it takes me a few minutes of frustration to figure out why AF doesn't work.

[kypfer]

A source of a/f frustration to me is trying to convince the camera which subject to focus on when trying to picture a flying bird against a background of rippling water, looking down on the sea or reservoir, for example. With so many flickering highlights to choose from the camera seems to "throw it's hand up" and focus down to minimum distance


The manual for my *ist DL2, on p.123 quotes "Wide - The camera targets the wide area in the centre of the screen (within the focussing area) and focusses on the nearest object". I'll admit to not having tried this camera for "birding" in these circumstances, but it'd be really nice if the newer models did this as well, unfortunately the manuals for my other cameras refer to "optimum" rather than "nearest"

[schnur07]

I figured out what was going on. When I push the AF Mode, the dial on the front of the camera changes the AF mode (AF S, AF C, AF A) and the dial on the back of the camera changes the focus points (27, 9, spot, etc). You can also change the focus points through the menu. Not sure if AF Mode using the dial is the default setup or if the person I bought this from recently had it set up that way. Anyway, I figured it out.

Now I just need to figure out which mode is best for my kids soccer and basketball games - when they are able to start playing again...

---------- Post added 03-26-20 at 06:50 PM ----------

Another benefit of AF.C is linked to the AF points themselves. You can use just the centre point as in AF.S: many people do. However there’s additional functionality using the 27 points. In the auto mode, the camera selects what it wants to focus on - this was true right back to my *istDS. But in the select mode in AF.C (I use the centre square of 25 cross-type points), if you activate AF with the subject under the centre red square and continue to hold the AF button then the AF will track the subject across the focus points. Not perfect, not predictive but better than many think.

So you're saying that if I have it in AF C mode and then SEL mode with the red dot in the center, if I focus on a moving object (e.g soccer player), it should maintain focus on that player?

[microlight]

So you're saying that if I have it in AF C mode and then SEL mode with the red dot in the center, if I focus on a moving object (e.g soccer player), it should maintain focus on that player?

Yes, if you place the centre red square on the subject as you activate the AF (recommend back-button-focus if you don't already do it) that's what should happen. I use SEL-3 on my K-3II, which is the 25-point setting, as I rarely shoot fast moving stuff like sports. I think that the 9-point setting (don't know which that is on the KP but the camera will show you on the info screen) reacts more quickly as there are fewer points to concentrate on, so that might be better in your situation. Also, don't forget the 'hold AF status' in the custom menu - if the player you're focusing on has someone running in front of them, you don't want the camera instantly re-focusing, so that might need turning on to maybe medium, or even higher depending on your situation.


Also, don't forget that speed of AF reaction depends a great deal on how quickly your lens focuses. This may be one reason why Pentax AF gets a bad rep. I use the PLM55-300 for long shots and it's lightning fast (although not a wide aperture) whereas the first version SMC55-300 that I had previously was slow, and a bear for hunting around.

[rogerstg]

So you're saying that if I have it in AF C mode and then SEL mode with the red dot in the center, if I focus on a moving object (e.g soccer player), it should maintain focus on that player?

You need to select selS, selM or selL on the KP to enable this. SEL mode only lets you select the focus point. It doesn't auto track or adjust focus during action. These modes let you select the initial focus point and track focus. The manual explains it more fully.