[stevebrot]

Buffer clearing was quite slow, taking a glacial 48 seconds to clear a burst of 74 JPEGs, 31 seconds after a max-length burst of RAW files, and 34 seconds after a max-length RAW+JPEG burst, when tested with our 95MB/s SanDisk Extreme Pro UHS-I card. (Unfortunately, the Pentax K-1 is not UHS-II compliant.)

Oh, I thought you meant something related to AF.

Buffer clearing time has been discussed on other threads along with frame rates with various cards. A couple users are reporting lower than the 17 image buffer on burst. I don't remember the time to clear with production firmware. IIRC, Adam has done work characterizing the behavior with different cards and I expect that it will be covered in the PF detailed review.


Steve

[stevebrot]

Buffer clearing time has been discussed on other threads along with frame rates with various cards.

https://www.pentaxforums.com/forums/190-pentax-k-1/321368-k1-buffer-fills-up-quick-seems.html

https://www.pentaxforums.com/forums/190-pentax-k-1/321296-write-speed-sd-card-test.html


Steve

[RockvilleBob]

I look forward to the PF review - to me it is all related - if I focus on capturing wildlife action shots my experience has been AF tracking, frame rate and buffer throughput control how many good shots I get during a wildlife sequence. If the camera cannot track the sequence I miss shots, if the frames per second is slow I may miss a shot and if the buffer fills and I cannot shoot anymore I miss shots. Moving from the K5 to the K3 improved all three and improved my keeper rate and good shots per outing, but I feel the K3 is still not up to a competitive level. At 4 fps I would expect an extremely high keeper rate and a buffer that doesn't quickly fill. So to hear the buffer throughput is slow is concerning and it is good to hear that the Pentax Forum will look at this. So perhaps from your point of view it is not AF but from my point of view after getting myself in a position to capture an action sequence when I properly focus on the object but get a low yield it is an autofocus issue. The camera is not getting enough good shots - again assuming I did what I could correctly.

[monochrome]

I suspect your use case will be demanding for K-1.

[ogl]

I think that K-3's replacement with SAFOX 12 would be better in terms of AF than K-1...At least for dense covering of APS-C frame with 33 AF points.

[Barry Pearson]

I look forward to the PF review - to me it is all related - if I focus on capturing wildlife action shots my experience has been AF tracking, frame rate and buffer throughput control how many good shots I get during a wildlife sequence. If the camera cannot track the sequence I miss shots, if the frames per second is slow I may miss a shot and if the buffer fills and I cannot shoot anymore I miss shots. Moving from the K5 to the K3 improved all three and improved my keeper rate and good shots per outing, but I feel the K3 is still not up to a competitive level. At 4 fps I would expect an extremely high keeper rate and a buffer that doesn't quickly fill. So to hear the buffer throughput is slow is concerning and it is good to hear that the Pentax Forum will look at this. So perhaps from your point of view it is not AF but from my point of view after getting myself in a position to capture an action sequence when I properly focus on the object but get a low yield it is an autofocus issue. The camera is not getting enough good shots - again assuming I did what I could correctly.

I suspect your use case will be demanding for K-1.

Yes. The K-1 isn't the perfect camera for (say) birds in flight. But it isn't hopeless either.

I've just posted here with some links to where I've been recording my experiences elsewhere.

If that sort of photography were my main activity, I wouldn't use a K-1. But for someone like me who wants a good all-round camera that can also be used for "things in flight" as well, albeit with extra effort, it is worth considering.I certainly don't regret buying it, and I'm getting results, some of which are posted where they can be found via the above link.

But - I think there is a learning curve for how to get the best out of it, with the many AF settings, and there isn't yet a consensus. I think Ricoh are not helpful with their operating manual, and I don't know of anywhere to go where it says "for this sort of action photography, these are the settings to use". Some of my posts via the above link are my own attempt to build my own guidelines. I'm reasonably comfortable for airshows and motor sports, but I'm still searching for the best combinations for (say) "medium sized bird in flight".

[RockvilleBob]

Thanks for posting all your observations Barry. I find them very helpful and appreciate your effort.

[carolina_sky]

Yes. The K-1 isn't the perfect camera for (say) birds in flight. But it isn't hopeless either.

I've just posted here with some links to where I've been recording my experiences elsewhere.

If that sort of photography were my main activity, I wouldn't use a K-1. But for someone like me who wants a good all-round camera that can also be used for "things in flight" as well, albeit with extra effort, it is worth considering.I certainly don't regret buying it, and I'm getting results, some of which are posted where they can be found via the above link.

But - I think there is a learning curve for how to get the best out of it, with the many AF settings, and there isn't yet a consensus. I think Ricoh are not helpful with their operating manual, and I don't know of anywhere to go where it says "for this sort of action photography, these are the settings to use". Some of my posts via the above link are my own attempt to build my own guidelines. I'm reasonably comfortable for airshows and motor sports, but I'm still searching for the best combinations for (say) "medium sized bird in flight".

Barry, heartily agree. I think it's up to us forum denizens to document the right settings (and the limitations) for different situations. I also do photography at horse shows, though this is not my primary use case. The better low light, higher pixel count and overall image q of K1 are highly appealing there. My experience from a weekend at a show is that the K-1 is better than K-3 there, but there seem to be still some significant AF limitations. My keeper rate is better, but I'm definitely losing some shots when the camera doesn't respond quickly enough, and I can't figure out any good reason for this. And I'm not doing tracking or burst shooting. I'm going to have to go through various settings and tests to see. At the moment, low light (or deep shadows) seems to be a factor.

[stevebarnes]

I'm sorry to hear of your bad experience. I've had Pentax K100D, K100D, K3 and now K1. The K1 worked fine when my Tamron 70-200 f/2.8 DI LD IF whatever else (2 years old now ). But when I bought the new Pentax 24-70 f/2.8 or just wouldn't focus properly. Manual mode for beautiful results, like yours. I rang CR Kennedy, Australian importer, and they asked me to visit. They spent an hour recalibrating my new lens to my K1. It is now just fantastic. Maybe you're having a parallel experience.

Using the 15-30 lens.

I am at the Mont St Michele Abbey on the west coast of France now, tried to focus on a large stone tower at infinity and every time it lands somewhere different. I have tested it in manual focus and found the perfect point of sharpness, but then move over to AF and its clearly not going to the same spot, it will do it 1 in 5 maybe.

Also latest firmware 1.10

[Sweets]

I think almost everyone else with the k-1 has been ecstatic over the great auto-focus, so your experience is clearly an exception. Whether that is due to a faulty camera, camera settings or your not being used to small DSLRs remains to be seen.

The obvious thing to check is what focus mode your are in. If you have it in AF.S and spot then your focus should be repeatable, mine certainly is. If however you are using Auto multi-point or Select multi-point then the camera has a number of focus points to use and will select the one it thinks best, which in many situations will not be the same one as the last time due to changing lighting, very slight movement of the camera and so on.

So to see if the camera is faulty, put it in AF.S and spot (single point) mode. Put it on a tripod and test the focus, it should always give the same result. If it is still giving inconsistent results I would suggest returning it as defective as this is not normal behavior.

+1 here.
I did send mine to repair and while I also had to adjust my Pentax glass for front/back focusing before that, after receiving from repair all Pentax glass I own are spot on without focus adjustment in-camera settings.

[wanderer2]

I don't have a 15-30 but for shooting landscapes with four other lenses I've had no focusing problems using BBF, AF-S, and movable single focus point. Focusing is quick and accurate and BBF holds the focus setting until it's changed, thus no difficulty holding infinity as the OP described, (or any other focus distance). The only time there's any problem is if the focus point is on a totally homogeneous area of the image such as a cloudless sky and then it's usually easy to move the focus point to another area. BBF with the shutter release button focusing, or whatever it's properly called, disabled might solve at least part of the OP's problem but, as mentioned above, I'm not using a 15-30 (wish I had one) so I can't be certain. But I would suggest giving this method a try if you haven't already.

[stevebarnes]

Which lens(es) are you using? My experience is completely contrary to yours.

RichIsDoomed???

[Winder]

That's what I am doing and it's working fine.

I am also seeing a little shot to shot inconsistency with sharpness once correctly focused so will also be testing the SR on and off as well.

Can anybody offer advice on what focus distance I should look to test for Fine Focus Adjustment on a 15mm lens? 5m, 10m, infinity?

Did you ever get the AF issue resolved? I have been pretty outspoken about the below average AF performance of the K-1, but it is significantly better than the AF in the 645z that you have. Outside of tracking moving subjects in mixed and low-light it performs very well. For travel and landscape photography its probably the best DSLR you can buy.

[Jeffvan]

I am a recent owner of a K-1 and find the Autofocus quite lacking. For still shots it is easy to use focus peaking in live view and get excellent results, but I found the following conditions to be too much for the K-1: dark color tones (in bright light), moving targets (with central spot auto focus in AFC).

K-1 firmware 1.41.
I use AF.C with back button focus and Central Spot and Focus Priority in the following examples (the red lines indicate the in focus plane). I placed the Central Spot on the Dog's faces (right between the eyes):

With dark color tones you just don't know what you will get. It most commonly is front focus or back focus but almost never on target.
Here is a nice high contrast subject, a white dog with a black snout running towards me. This was the only shot in focus of any of the dogs running towards me. The focus is right on target, maybe a bit front focus..


Here is a brown dog as the subject, running towards me. With the light conditions there should be enough contrast, especially with the Frisbee. But instead we get back focus. This is an example of most of the shots.


With 240 shots I got 4 in focus shots. One with a dog running towards me (the one above) and 1 of them running at 90 degrees to me. Two of the shots was with the dogs moving around each other and having high contrast between the two dogs.

With the brown dog as a moving target, here is some focus jumping sequences:




I find with the dogs, setting the spot on their heads, that I generally get back focus as they run towards me. It made me think that the auto focus is slow. The one in focus shot I got, might be a fortunate focus jump that just happens to get the right spot.

You can review some of the images yourself:
https://www.flickr.com/gp/153388317@N08/3515LG

In summation I would say there is a good likely hood of slow autofocus, or at least a significant delay between autofocus and shutter time. And I find random autofocus jumps that just don't make sense.
If anyone has any insight, I would really appreciate it!

As a landscape camera it is great! Really awesome pictures!

[angerdan]

I am a recent owner of a K-1 and find the Autofocus quite lacking.
For still shots it is easy to use focus peaking in live view and get excellent results, but I found the following conditions to be too much for the K-1: dark color tones (in bright light), moving targets (with central spot auto focus in AFC).

I use AF.C with back button focus and Central Spot and Focus Priority in the following examples (the red lines indicate the in focus plane).

Why not take advantage of all 33 AF points, which will increase the time between AF confirmation and shutter release?

With dark color tones you just don't know what you will get.
It most commonly is front focus or back focus but almost never on target.

Color or Brightness of one subject only doen't matter for AF, only the overall contrast (brightness or color).

With 240 shots I got 4 in focus shots.
I find with the dogs, setting the spot on their heads, that I generally get back focus as they run towards me.
It made me think that the auto focus is slow.

For moving objects, your focusing method is not fast enough to keep up with the runners. AF is so fast, you can only recognize the short change in the viewfinder (or with screw-driven lenses by sound of the motor).

In summation I would say there is a good likely hood of slow autofocus, or at least a significant delay between autofocus and shutter time.
And I find random autofocus jumps that just don't make sense.
If anyone has any insight, I would really appreciate it!

Reading about your method and issues and regarding your D FA* 70-200mm DC lens, i'm sure there's room for improvement.
Try following settings:

Menu 📷 Tab 1
Group Phase Detection AF
AF Mode: AF.C
AF Active Area: Expanded Area AF (L) or as alternative AUTO (33 AF Points)
1st Frame Action In AF.C: Focus Priority
Action In AF.C Cont.: Auto
Hold AF Status: Medium

Menu 📷 Tab 5
Group Viewfinder Overlay
Grid Display: Off