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02-18-2016, 12:08 PM - 1 Like   #1
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SAFOX 12 autofocus can indicate multiple points in focus!

Several years back, I wrote about how Pentax can improve their autofocus system. The most important factor I noted was to allow arbitrary combinations of AF points to work together and indicate focus at the same time:

QuoteOriginally posted by bwDraco Quote
Allow any number of AF points to work together, even if they are not connected to each other. This is the single most important thing Pentax can do to improve AF performance. It requires treating each point as a separate entity, yet allowing them to be used simultaneously in an arbitrary arrangement. Doing so eliminates many of the issues and limitations listed above and paves the way for much more advanced predictive tracking algorithms to be implemented. It may be possible to implement this for current cameras via a firmware update, but hardware limitations may prevent this from happening.
...and it appears that in the K-1, they've implemented just that. Notice that in the following video (starting from 0:26), arbitrary AF point combinations are indeed being shown:


This is a huge deal to me. With the overhauled AF and AE algorithms, this should mean a non-trivial improvement in tracking performance. Even though DPReview reports that the camera transitions to different points rather slowly, I suspect the keeper rate will be noticeably higher, even at the slower 4.4 fps full-frame (or 6.5 fps APS-C) continuous shooting rate.

Questions, thoughts, or comments? Is anyone with a pre-production K-1 able to confirm or deny this?

02-18-2016, 12:18 PM   #2
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QuoteOriginally posted by bwDraco Quote
Several years back, I wrote about how Pentax can improve their autofocus system. The most important factor I noted was to allow arbitrary combinations of AF points to work together and indicate focus at the same time:



...and it appears that in the K-1, they've implemented just that. Notice that in the following video (starting from 0:26), arbitrary AF point combinations are indeed being shown:

PENTAX K-1 SAFOX 12 - YouTube

This is a huge deal to me. With the overhauled AF and AE algorithms, this should mean a non-trivial improvement in tracking performance. Even though DPReview reports that the camera transitions to different points rather slowly, I suspect the keeper rate will be noticeably higher, even at the slower 4.4 fps full-frame (or 6.5 fps APS-C) continuous shooting rate.

Questions, thoughts, or comments? Is anyone with a pre-production K-1 able to confirm or deny this?
I think a bigger problem was the amount of time it took the camera to realize it was out of focus and to reacquire. A subject coming toward you would be in focus, but then as it approached, at some point it moved past the focal plane. The camera took a bit to realize it wasn't in focus anymore. It was reacquire the focus and repeat.

What needs to happen is a near constant focus and check system, almost always have the focus moving.
02-18-2016, 12:22 PM   #3
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Video looks nice, the video of the K-3 AF was also impressive , but when I got the K-3 at hand , I was less impression by the AF compared the AF performance of the marketing video.
02-18-2016, 12:25 PM   #4
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QuoteOriginally posted by enoeske Quote
I think a bigger problem was the amount of time it took the camera to realize it was out of focus and to reacquire. A subject coming toward you would be in focus, but then as it approached, at some point it moved past the focal plane. The camera took a bit to realize it wasn't in focus anymore. It was reacquire the focus and repeat.

What needs to happen is a near constant focus and check system, almost always have the focus moving.
You have the original K-3. The K-3 II addresses this issue: https://www.pentaxforums.com/forums/172-pentax-k-3/301750-japanese-blogger-te...provement.html

02-18-2016, 12:46 PM   #5
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QuoteOriginally posted by enoeske Quote
What needs to happen is a near constant focus and check system, almost always have the focus moving.
Yes, I think that is the single biggest problem with Pentax' AF system. It just doesn't reacquire focus quickly enough, even though I know the lens' AF drive would certainly be fast enough.
02-18-2016, 12:57 PM   #6
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Looks very promising!

Adam
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02-18-2016, 07:12 PM   #7
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QuoteOriginally posted by Adam Quote
Looks very promising!
Wow! I remember your comments about the K3 as being a bit of a disappointment. I thought you were a bit stingy at the time. If you are impressed I may have to preorder.

02-18-2016, 09:30 PM   #8
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QuoteOriginally posted by derekkite Quote
Wow! I remember your comments about the K3 as being a bit of a disappointment. I thought you were a bit stingy at the time. If you are impressed I may have to preorder.
Well, this reflects a fundamental change in the way the AF system operates, rather than the incremental tweaking that's been going on for years. It's commendable. I certainly wasn't expecting this kind of a development to be launched in the K-1, especially considering all the other new technologies that were needed to make the FF happen.

In my eyes, the only other truly impressive thing that Pentax accomplished in the AF department (prior to this) was the exceptional low-light AF sensitivity that came out on the K-5 II.

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02-18-2016, 10:30 PM   #9
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For reference, this video was published when the K-3 was released. Notice that this video depicts focus confirmation on only one AF point at a time:


If these videos are anything to go by, then SAFOX 12 represents a major step forward, providing focus confirmation on arbitrary combinations of AF points.

Canon, Nikon, and Sony phase-detection AF systems have always behaved in this fashion. It's about time Pentax caught up.

Once again, is anyone with a pre-production K-1 able to confirm or deny this?

---------- Post added 02-19-16 at 01:08 AM ----------

Some Tweets that may be worth quoting:

https://twitter.com/bwDraco/status/700559547774046208
https://twitter.com/bwDraco/status/700560645335285760
https://twitter.com/bwDraco/status/700561592421785600

---------- Post added 02-19-16 at 01:20 AM ----------

This full-size sample from DPReview might reveal more information. However, the latest version of ExifTool (10.11) does not currently understand the changes made to the "AF Points in Focus" field; it reports "Unknown (255)". 255 is the maximum value for a single unsigned byte, so there likely is a new field that holds the points-in-focus information. Because the camera would need to report that none, one, or many points are in focus in the Exif data, this likely confirms the change.

Last edited by bwDraco; 02-18-2016 at 11:43 PM.
02-19-2016, 12:16 AM   #10
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QuoteOriginally posted by bwDraco Quote
Several years back, I wrote about how Pentax can improve their autofocus system. The most important factor I noted was to allow arbitrary combinations of AF points to work together and indicate focus at the same time:



...and it appears that in the K-1, they've implemented just that. Notice that in the following video (starting from 0:26), arbitrary AF point combinations are indeed being shown:

PENTAX K-1 SAFOX 12 - YouTube

This is a huge deal to me. With the overhauled AF and AE algorithms, this should mean a non-trivial improvement in tracking performance. Even though DPReview reports that the camera transitions to different points rather slowly, I suspect the keeper rate will be noticeably higher, even at the slower 4.4 fps full-frame (or 6.5 fps APS-C) continuous shooting rate.

Questions, thoughts, or comments? Is anyone with a pre-production K-1 able to confirm or deny this?
I feel like the video is misleading because the frame is so heavily cropped. I was really hoping the AF points would cover more of the frame than in their other DSLRS, and by the looks of the video, one might get the impression that they do.
02-19-2016, 12:42 AM   #11
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QuoteOriginally posted by geomez Quote
I feel like the video is misleading because the frame is so heavily cropped. I was really hoping the AF points would cover more of the frame than in their other DSLRS, and by the looks of the video, one might get the impression that they do.
yeah I think the first video is in crop frame(APS-C)
and I wonder if they can illuminate the in-focus AF points with red square
instead of just black square in the production version
04-28-2016, 03:31 PM   #12
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QuoteOriginally posted by bwDraco Quote
Several years back, I wrote about how Pentax can improve their autofocus system. The most important factor I noted was to allow arbitrary combinations of AF points to work together and indicate focus at the same time:



...and it appears that in the K-1, they've implemented just that. Notice that in the following video (starting from 0:26), arbitrary AF point combinations are indeed being shown:

PENTAX K-1 SAFOX 12 - YouTube

This is a huge deal to me. With the overhauled AF and AE algorithms, this should mean a non-trivial improvement in tracking performance. Even though DPReview reports that the camera transitions to different points rather slowly, I suspect the keeper rate will be noticeably higher, even at the slower 4.4 fps full-frame (or 6.5 fps APS-C) continuous shooting rate.

Questions, thoughts, or comments? Is anyone with a pre-production K-1 able to confirm or deny this?
I am looking forward to the Forum review of the K-1 with regards to autofocus. I have the K3 and decided not to upgrade to the K3II because I got the impression while slightly improved the autofocus of the K3II was not that much better than the K3. I hope the review show the AF improvements you feel may be incorporated in the Pentax K1. The video is something I want to believe but then the K3 introductory autofocus video showed far better tracking than the K3 delivers in real world situations.
04-28-2016, 04:13 PM   #13
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QuoteOriginally posted by RockvilleBob Quote
I am looking forward to the Forum review of the K-1 with regards to autofocus. I have the K3 and decided not to upgrade to the K3II because I got the impression while slightly improved the autofocus of the K3II was not that much better than the K3. I hope the review show the AF improvements you feel may be incorporated in the Pentax K1. The video is something I want to believe but then the K3 introductory autofocus video showed far better tracking than the K3 delivers in real world situations.
On a related note, DPReview just published their full review of the Canon 80D and found that it shows the same issue as the K3 - in AF.C tracking it manages to correctly identify aa subject erratically moving towards the camera and activates the correct AF point, but fails to keep the focus on it, instead only refocusing when the subject has already left the focus plane.

At least we are not the only ones any more
04-28-2016, 04:53 PM   #14
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It's better for some things, annoying as hell for others. When you have a strong line passing through your shot, it's amazing (architecture, or street furniture). If however you're trying to focus on a pint glass, it's really annoying (it just focusses on the outer edges, and the centre is always out of focus). It does seems to offer some advantages with tracking, but try to keep your target at least 3m away! Overall i think it has improved the AF performance, and I do applaud pentax/ricoh, but i suspect some product photographers will end up preferring the old K-3 system.
04-28-2016, 05:30 PM   #15
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QuoteOriginally posted by robthebloke Quote
If however you're trying to focus on a pint glass, it's really annoying (it just focusses on the outer edges, and the centre is always out of focus).
How many pints had you had when you tried this? I know after a couple sometimes the edges are sharp and the center fuzzy. Or is it the centre sharp and the edges fuzzy.................... <joking>
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