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11-20-2022, 01:01 PM   #1
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Still struggling with AF

I'm noticing a frustrating pattern with AF in both Live View and OVF.

Using AF-C, Zone Auto, the camera has a tendency to pick the water below the bird. This is a pretty high contrast bird, so one would think with the subject recognition it shouldn't have an issue.


This one was taken in Live View - AF - repeat attempts to re-focus kept resulting in the green boxes selecting the water just below the bird, to the right of his reflection in the water.




In this photo, Live View, AF-C, Zone Auto was selected. Zooming in on the back of the camera to the selected focus point shows it focused right on the high-contrast portion of the bird's head/neck. It clearly didn't do a good job.




Back in Live View, 9 point AF, it zooming in on the focus point on the back of the camera shows it supposedly selected the top dark feathers just above the tail feather. I don't see any part of the image that's in focus...




This one was the better of the Birds In Flight photos, oddly using center point select in AF-C





Anyway, lots of examples from this outing where the image just wasn't in focus where the focus point landed. Many were OK, but overall just a consistently inconsistent experience. Take 5 photos, hope one is in focus. These are the frustrations I had with the K5 and primarily the reason I bought the K3-3, but I see little has changed. It's frustrating - I feel like I have maybe 5 photos of the 240 I took that are facebook-worthy. None suitable for printing. What am I doing wrong? The only ones that were decent were the small blackbirds in the tree 3 meters away from me. All taken with the 55-300plm.

11-20-2022, 01:34 PM - 1 Like   #2
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I can't offer any advice but my experience recently in South Africa was much the same. No real problem with larger animals but anything smaller and with long grass behind the focus often missed.
11-20-2022, 02:33 PM   #3
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I have had issues getting AF to focus on subjects on water, and I think others have also commented on this.
I have no solution to offer.

Cheers,
Terry
11-20-2022, 02:57 PM - 3 Likes   #4
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Unless it is very still, water is hard because there are many many high contrast spots that continually move. Single spot through the viewfinder works better than anything else for me, but I've never used live view in this type of image, because I wouldn't use a tripod shooting birds, only for landscapes of non moving subjects.

11-20-2022, 03:13 PM - 3 Likes   #5
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Single spot AF is probably the go for these shots.
11-20-2022, 03:26 PM - 2 Likes   #6
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This is "normal" … the ripples on the water keep changing and they seem to "catch the attention" of the a/f system.
My solution is to use a single (central) a/f point through the OVF, preferably with AFS, unless it's a flying bird, in which case use AFC, but be prepared to practice your panning … you need to keep that central point on the subject
With the K-3iii the concept isn't too difficult if the lens is steady … you'll struggle a bit if the lens is blowing about!
Having "fine tuned" my birding with my K-70 and then my KP, achieving a reasonable success rate with the K-3iii isn't too difficult, but practice is the key word
Unfortunately multi-point a/f only seems practical against a clear sky or if the subject is really quite close … then it does work well
There's no mention of which lens was used, but I've had no luck trying to use a telephoto with LiveView unless it was mounted on a tripod.
Remember, with AFC the shutter will release even if the image is not in focus … you really do need to keep an eye on the green hexagon focus confirmation indicator in the viewfinder … the "beep" may help as well, but I don't use it myself.
Also note, birds with white in the plumage such as gulls will often over expose against the relatively dark background of water unless they're reasonably large in the viewfinder. I tend to use one stop under-exposure compensation in cases like this in bright sunlight.
Good luck
11-20-2022, 04:02 PM   #7
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QuoteOriginally posted by kypfer Quote
There's no mention of which lens was used
Yes, the lens in question is the 55-300 PLM. I know what the OP means by it wanting to choose focus points around the subject. It is an excellent lens by it can be frustrating.

11-20-2022, 04:09 PM - 4 Likes   #8
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Time to switch to manual focus.
11-20-2022, 04:19 PM   #9
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QuoteOriginally posted by luftfluss Quote
Time to switch to manual focus.
Thank you, Yoda. It should have been "To focus manual you should switch".

May the Force be with you!
11-20-2022, 04:55 PM - 2 Likes   #10
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I've noticed the same issues whether using my K3III, K-70, or Nikon D500. Rippling water makes AF far less reliable. Full-on waves are friendlier.
11-20-2022, 05:28 PM - 4 Likes   #11
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QuoteOriginally posted by sebberry Quote
I'm noticing a frustrating pattern with AF in both Live View and OVF.

Using AF-C, Zone Auto, the camera has a tendency to pick the water below the bird. This is a pretty high contrast bird, so one would think with the subject recognition it shouldn't have an issue.


This one was taken in Live View - AF - repeat attempts to re-focus kept resulting in the green boxes selecting the water just below the bird, to the right of his reflection in the water.




In this photo, Live View, AF-C, Zone Auto was selected. Zooming in on the back of the camera to the selected focus point shows it focused right on the high-contrast portion of the bird's head/neck. It clearly didn't do a good job.




Back in Live View, 9 point AF, it zooming in on the focus point on the back of the camera shows it supposedly selected the top dark feathers just above the tail feather. I don't see any part of the image that's in focus...




This one was the better of the Birds In Flight photos, oddly using center point select in AF-C





Anyway, lots of examples from this outing where the image just wasn't in focus where the focus point landed. Many were OK, but overall just a consistently inconsistent experience. Take 5 photos, hope one is in focus. These are the frustrations I had with the K5 and primarily the reason I bought the K3-3, but I see little has changed. It's frustrating - I feel like I have maybe 5 photos of the 240 I took that are facebook-worthy. None suitable for printing. What am I doing wrong? The only ones that were decent were the small blackbirds in the tree 3 meters away from me. All taken with the 55-300plm.

Hi Sebbles,

There are so far at least two of my articles that may be relevant to your situation:

Clackers' Beginners Tip 14: Focusing on a subject - PentaxForums.com

Clackers' Beginners Tip 29: Focus Point Size - PentaxForums.com

I think the main thing is to be the photographer, emulate the pros by taking control from the camera, choosing in these instances single point AF focus (there are additional advantages to BBF when taking a series of shots).

When using a 'high tech' Sony A1 to shoot surfers, I was told by the instructor to make the zone fields as small as possible because algorithm driven autofocus ended up concentrating on nearby waves.

Cheers,
Ian
11-20-2022, 07:09 PM - 4 Likes   #12
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QuoteOriginally posted by Paul the Sunman Quote
Single spot AF is probably the go for these shots.
QuoteOriginally posted by clackers Quote
hoosing in these instances single point AF focus
Yea, verily.

I almost never deviate from having my cameras have focus on the single, central spot - that's almost always where the action you want is.

If everybody had their camera set up this way, I think we would see a lot fewer complaints about focus! (imnsho!) Of course, you still need contrasty object(s) in the middle of the frame (that are not dominated by sparkly waves off to the side).
11-20-2022, 08:17 PM - 3 Likes   #13
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QuoteOriginally posted by PJ1 Quote
Thank you, Yoda. It should have been "To focus manual you should switch".

May the Force be with you!
11-20-2022, 08:55 PM - 2 Likes   #14
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QuoteOriginally posted by sebberry Quote
I'm noticing a frustrating pattern with AF in both Live View and OVF.

Using AF-C, Zone Auto, the camera has a tendency to pick the water below the bird. This is a pretty high contrast bird, so one would think with the subject recognition it shouldn't have an issue.


This one was taken in Live View - AF - repeat attempts to re-focus kept resulting in the green boxes selecting the water just below the bird, to the right of his reflection in the water.




In this photo, Live View, AF-C, Zone Auto was selected. Zooming in on the back of the camera to the selected focus point shows it focused right on the high-contrast portion of the bird's head/neck. It clearly didn't do a good job.




Back in Live View, 9 point AF, it zooming in on the focus point on the back of the camera shows it supposedly selected the top dark feathers just above the tail feather. I don't see any part of the image that's in focus...




This one was the better of the Birds In Flight photos, oddly using center point select in AF-C





Anyway, lots of examples from this outing where the image just wasn't in focus where the focus point landed. Many were OK, but overall just a consistently inconsistent experience. Take 5 photos, hope one is in focus. These are the frustrations I had with the K5 and primarily the reason I bought the K3-3, but I see little has changed. It's frustrating - I feel like I have maybe 5 photos of the 240 I took that are facebook-worthy. None suitable for printing. What am I doing wrong? The only ones that were decent were the small blackbirds in the tree 3 meters away from me. All taken with the 55-300plm.
There are a bunch more contrast edges in the water than the back of the duck the camera is obviously going to chose the water. Just curious, why are you using Live View in this situation? Are you shooting tripod mounted? You are giving the camera too many choices you need to limit the AF area.
11-21-2022, 12:22 AM - 4 Likes   #15
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As guys above said - use center AF. Anything else and camera will get confused more often then not. I am not a birder, but even with something as big as Airbus 330 or B737 it tends to get interested in weird things when plane is close to ground. I was using auto for some time, then various SEL options and ended on center point cause I was often getting focus on yellow runway signs instead of plane.


If subject is easily defined for software to recognize then there is no problems. Eyes are one of such thing. They look more or less same on everyone and what is left is computing speed and fast AF drive. With animals it is not so obvious and with just "moving" subject it is guessing what the meatbag behind camera wants. And when everything moves you get the results you got.


AUTO/Zone AF is like a puppy. It tries to do what you want, but there are soooo many interesting things in the world to sniff

And there is also issue that focus point coverage on AF sensor is really limited. You have only so many points and if you want focus somewhere in between it will miss. Harsh realities of DSLR.

Last edited by jersey; 11-21-2022 at 02:30 AM.
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