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07-27-2021, 07:54 PM   #31
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QuoteOriginally posted by Kobie Quote
I tried something today regarding AF.C. I was doing some deep thoughts as to why the AF seems to act erratically and I started thinking about other functions that seemingly didn't work correctly on previous Pentax cameras. Namely Catch in focus and how it doesn't work when using back button focus. So I changed from back button focus to shutter button focus and WOAH!!! The accuracy of AF drastically improved! It no longer picked things way off in the background or to the side. I did this with full auto AF to see if either bbf or sbf would make a difference and it did. I'm a back button shooter, but for now I'm going to stick with shutter button only and see if it remains more accurate.
https://youtu.be/1lncsu_c6So
I just did a quick test sitting on my couch shooting various subjects around the living room in low light and my Mk III never waivered it locked exactly where the camera was focused, every single time! The only way I could throw it off was to move the focus point and then focus where the center focus area is in the viewfinder. Even when moving the focus array to the extreme corners the focus was still spot on. You've got something else going on with your camera. So I'm staying with BBF.


Last edited by Larrymc; 07-27-2021 at 08:00 PM.
07-27-2021, 08:47 PM   #32
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QuoteOriginally posted by Larrymc Quote
I just did a quick test sitting on my couch shooting various subjects around the living room in low light and my Mk III never waivered it locked exactly where the camera was focused, every single time! The only way I could throw it off was to move the focus point and then focus where the center focus area is in the viewfinder. Even when moving the focus array to the extreme corners the focus was still spot on. You've got something else going on with your camera. So I'm staying with BBF.
Full auto AF. You can't move the focus points around in that mode. SEL works well. I'm talking about the auto AF system which is the jumpy one.
07-28-2021, 06:17 AM - 3 Likes   #33
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QuoteOriginally posted by Kobie Quote
Full auto AF. You can't move the focus points around in that mode. SEL works well. I'm talking about the auto AF system which is the jumpy one.
What you are saying is that you are letting the camera chose the focus point, is that correct? Why ever use that feature?
07-28-2021, 06:53 AM - 1 Like   #34
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Eaxatly this was my question in the parallel topic "AF.C Auto weirdness when using back-button AF?"

Who uses full Auto when he defently know what to focus...

07-28-2021, 07:15 AM - 1 Like   #35
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Subject recognition only works in the auto area modes, and it’s generally quite good. I use my smart function to toggle away from auto area if it’s not working properly, but it generally works right and allows for quicker reactions since you don’t need to relocate the selected focus point.
07-28-2021, 08:21 AM   #36
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QuoteOriginally posted by mtkeller Quote
Subject recognition only works in the auto area modes, and it’s generally quite good. I use my smart function to toggle away from auto area if it’s not working properly, but it generally works right and allows for quicker reactions since you don’t need to relocate the selected focus point.
Exactly
07-28-2021, 09:04 AM - 2 Likes   #37
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QuoteOriginally posted by mtkeller Quote
Subject recognition only works in the auto area modes, and it’s generally quite good. I use my smart function to toggle away from auto area if it’s not working properly, but it generally works right and allows for quicker reactions since you don’t need to relocate the selected focus point.
Subject recognition didn't work in Kobie's video, because no subject which the camera was trained to recognize was in the frame. Unless it "worked" through false positives... is that part of the tree a "bird"? Maybe it was.
Instead, the camera relied on contrast. I do not believe that Auto Area would prioritize the center point, so this expectation should be revised, too.

L.E. By the way, I appreciate Kobie's efforts, and I'm sorry for not being able to help him (since I didn't buy the K-3iii).


Last edited by Kunzite; 07-28-2021 at 10:13 AM.
07-28-2021, 10:35 AM - 1 Like   #38
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QuoteOriginally posted by Kunzite Quote
Subject recognition didn't work in Kobie's video, because no subject which the camera was trained to recognize was in the frame. Unless it "worked" through false positives... is that part of the tree a "bird"? Maybe it was.
Instead, the camera relied on contrast. I do not believe that Auto Area would prioritize the center point, so this expectation should be revised, too.

L.E. By the way, I appreciate Kobie's efforts, and I'm sorry for not being able to help him (since I didn't buy the K-3iii).
Pretty sure the issue with Kobie’s test case is what was pointed out above: this is not an AF.C subject. I find that my results using AF.C on static subjects are really bad, and so if I’m set up for shooting action, my smart function dial is 100% giving me a way to toggle between AF.S and one of my two AF.C setups. Then if I catch something static that I want to capture, I will quickly switch over to AF.S since AF.C definitely seems to be looking for anything that it can call motion as part of its way to locate a subject.
07-28-2021, 10:55 AM - 1 Like   #39
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QuoteOriginally posted by mtkeller Quote
Pretty sure the issue with Kobie’s test case is what was pointed out above: this is not an AF.C subject. I find that my results using AF.C on static subjects are really bad, and so if I’m set up for shooting action, my smart function dial is 100% giving me a way to toggle between AF.S and one of my two AF.C setups. Then if I catch something static that I want to capture, I will quickly switch over to AF.S since AF.C definitely seems to be looking for anything that it can call motion as part of its way to locate a subject.
Directly taken from Ricoh's site....
"High-precision continuous shooting in AF.C mode
The camera’s continuous autofocus (AF.C) mode allows you to maintain sharp focus on a subject, regardless of direction of motion. An improved motion prediction algorism accurately detects the subject’s complex movement, which was rather difficult to predict with previous models. It also reduces the effect of the unstable motion speed and irregular stops and restarts, as well as the effect of obstacles." Click here for the site

Obviously using AF.C on a static object, say, a flower, will have the AF jumping everywhere since there's a zillion similar points for the camera to focus on (flower petals, leaves etc) but a sign that takes up most of the frame is a different story. I also didn't sit there with the AF.C going while waiting for "a shot". It was a quick acquisition to test the initial target when AF.C is activated. This is a new territory for us all as Pentax Shooters, I'm just sharing my findings. Ricoh themselves even state that the new system is better at detecting "unstable motion speed and irregular stops" So even if the subject is static, it will still work within a reasonable acquisition timeframe.

Again, just sharing the things I find, that's all.
07-28-2021, 11:54 AM - 2 Likes   #40
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Thank you again, Kobie. As another user already said: big effort, thank you for this. I've always the fear, that people who invest a lot doing things like you, stop doing this, when someone critical ask something in between.
So don't be offended for example for my critical questions :-)
I like your videos.
07-28-2021, 12:32 PM   #41
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QuoteOriginally posted by licht96 Quote
Thank you again, Kobie. As another user already said: big effort, thank you for this. I've always the fear, that people who invest a lot doing things like you, stop doing this, when someone critical ask something in between.
So don't be offended for example for my critical questions :-)
I like your videos.
No offense taken at all, don't worry.
Many of these elements are hard to explain in a way that everyone can understand since well, let's face it... Not everyone is technical. With that said, there's also the possibility of an issue with my camera or the batch mine came from which wouldn't affect all K-3 III users. So, I just share what I find as I use the gear. Just because it doesn't happen to everyone, doesn't mean it just flat out doesn't happen at all.

Last edited by Kobie; 07-28-2021 at 12:44 PM.
07-29-2021, 01:42 PM   #42
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QuoteOriginally posted by Kobie Quote
Namely Catch in focus and how it doesn't work when using back button focus.
Just to be clear, by this you mean that holding the rear AF button with catch in focus enabled does nothing? This is not surprising, since the AF button is not the shutter button. For anyone had questions after reading the bit I quoted, I have just tested and can confirm that with the camera set for back button focus (no AF via the shutter button), if I hold down the shutter button and focus a manual focus lens, the camera trips the shutter when it detects focus. To me this is not any difference in behavior between shutter button and back button for focus.
07-29-2021, 03:01 PM   #43
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QuoteOriginally posted by mtkeller Quote
Just to be clear, by this you mean that holding the rear AF button with catch in focus enabled does nothing? This is not surprising, since the AF button is not the shutter button. For anyone had questions after reading the bit I quoted, I have just tested and can confirm that with the camera set for back button focus (no AF via the shutter button), if I hold down the shutter button and focus a manual focus lens, the camera trips the shutter when it detects focus. To me this is not any difference in behavior between shutter button and back button for focus.
On my K-30 and K-3 with back button focus and catch in focus enabled, holding down the back button while pressing the shutter button and manually focusing will trip the shutter immediately regardless of focus confirmation. Putting either of the cameras back into shutter button focus will not trip the shutter until focus is confirmed while using catch in focus. And yes, they are set to focus priority.
07-29-2021, 03:20 PM - 1 Like   #44
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I don't have the III yet just my I. However in my experience catch-in-focus seems to slow down the whole AF-exposure sequence and often leads to missed shots. Since I set C 15, 16, 17 to focus priority, and C 18 to High, I get many more keepers than I ever did before. And I always use the rear AF button. Just my ¢¢.

Last edited by wtlwdwgn; 07-29-2021 at 04:02 PM.
08-05-2021, 05:46 AM - 4 Likes   #45
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Minor advantage discovered, important to me as a distractive photographer. Many times I shoot and .... BIP BIP BIP BIP everything's dark. DAMN!!! The self timer, I forgot it. Well there is a "!" sign in the viewfinder that inform you.
That sign is present for other reasons also, but to relevant one to be is this.

Maybe could help someone else as well
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