bit of a beef with k3

stevebrot · 04-04-2015, 04:28 PM

Originally posted by kjpino

So if that is the case then what exactly is the rear AF button for?

Focusing...The intent is to separate the focus function from the shutter function. Focus and recompose is the intended use case.

Steve

Last edited by stevebrot; 04-04-2015 at 05:19 PM.

stevebrot · 04-04-2015, 05:31 PM

Originally posted by kjpino

Okay - maybe I am misunderstanding your post... Are you saying that a 'bug in the code' caused previous Pentax cameras to fire the shutter at the exact moment focus was achieved when using the button labeled AF? So that 'bug in the code' now being fixed has resolved the 'problem' of amazingly well focused photos when shooting moving targets by 'fixing' the AF button to no longer cause it to communicate focus lock with the shutter release?

Having the back button AF emulate a type of CIF is not in the manual. It is sort of a bonus feature based on the fall-back behavior for corner cases outside the intended usage. In my line of work (software development) that is called graceful degradation. In the case of cameras other than the K-3 it resulted in happy coincidence for some users. CIF itself is sort of a similar situation and was discovered by accident by users not too long after I bought my K10D. CIF is now a supported feature and is included as such in the user manuals for new Pentax dSLRs.

Steve

stevebrot · 04-04-2015, 05:58 PM

Originally posted by jatrax

Can that be set in a user mode?

Yes, that is the work-around.

I can understand some of the frustration. This hidden feature of back-button focus has been popular for some users since the set-up and sequence was first described on this site some years ago. It allows the user to effectively toggle between the equivalents of AF-1 and AF-2 by simply changing the sequence of how two buttons are used with CIF being leveraged to trigger the shutter. The technique is hinted at in the user manuals, but not explicitly spelled out.

Why it went away is a bit of a mystery, but then again so are other things like requiring conductive base on the lens to do CIF.

Steve

stevebrot · 04-04-2015, 06:44 PM

Originally posted by kjpino

Exactly! Why would they have BB Focus in the K3 suddenly ignore focus priority?

Originally posted by stevebrot

Perhaps because it is not that important to many users?

OK...I just spent a half hour or so researching the K-5 features and playing the various settings of the K-3 and FINALLY caught the gist of the beef. It is the magical override of the focus priority to "off" if the AF button is set to AF-2. Yes, this is inconsistent. I would prefer that focus priority be retained for this case regardless of whether CIF is provided. For the "Cancel AF" setting, it would be nice if CIF was provided. After all, the viewfinder says "MF" and CIF is a feature of manual focus, but the current behavior is acceptable.

Steve

jayman_1975 · 04-04-2015, 10:22 PM

I just noticed my new k5IIs will Fire the shutter regardless of focus status when focus priority is set to "only release shutter when focus is achieved". So maybe it's a firmware thing cause my old k5II wouldn't fire when not in focus. I wish I knew what firmware version that one had but I sold it awhile ago. I wonder if there's a way to find out what firmware version it had by using one of its pictures like the way you can check shutter count by uploading it to a website

stevebrot · 04-04-2015, 11:42 PM

Originally posted by jayman_1975

I wonder if there's a way to find out what firmware version it had by using one of its pictures like the way you can check shutter count by uploading it to a website

The makernotes portion of the exif has the firmware version, though the file must be an in-camera JPEG or RAW from camera.

Steve

**bobbotron** · 04-12-2015, 05:12 PM

I've been caught by this a few times in action situations where I thought the focus was spot on, interesting to see BBAF is a possible solution to this. What does CIF stand for?

kjpino · 04-12-2015, 05:59 PM

Originally posted by bobbotron

I've been caught by this a few times in action situations where I thought the focus was spot on, interesting to see BBAF is a possible solution to this. What does CIF stand for?

ON the previous cameras BBAF would allow for this as BBAF could be used for CIF (Catch in Focus) - on the K3 it cannot - and that seems odd... Why would they take this option of that feature away? It means that if you use BBAF you can count on it for anything involving movement (kids, sports, wildlife, etc.)...

**monochrome** · 04-12-2015, 07:24 PM

I wonder if it has anything to do with the improved tracking AF?

kjpino · 04-13-2015, 05:08 AM

It just makes me constantly have to switch auto focus settings in the menu - which is kind of a pain... especially after being so used to it on previous Pentax cameras and now having to retrain myself - and jumping from y K3 to my K7 and back is confusing since the BBAF works differently on each...

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04-04-2015, 04:28 PM	#31
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by kjpino So if that is the case then what exactly is the rear AF button for? Focusing...The intent is to separate the focus function from the shutter function. Focus and recompose is the intended use case. Steve Last edited by stevebrot; 04-04-2015 at 05:19 PM.

04-04-2015, 05:31 PM	#32
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by kjpino Okay - maybe I am misunderstanding your post... Are you saying that a 'bug in the code' caused previous Pentax cameras to fire the shutter at the exact moment focus was achieved when using the button labeled AF? So that 'bug in the code' now being fixed has resolved the 'problem' of amazingly well focused photos when shooting moving targets by 'fixing' the AF button to no longer cause it to communicate focus lock with the shutter release? Having the back button AF emulate a type of CIF is not in the manual. It is sort of a bonus feature based on the fall-back behavior for corner cases outside the intended usage. In my line of work (software development) that is called graceful degradation. In the case of cameras other than the K-3 it resulted in happy coincidence for some users. CIF itself is sort of a similar situation and was discovered by accident by users not too long after I bought my K10D. CIF is now a supported feature and is included as such in the user manuals for new Pentax dSLRs. Steve

04-04-2015, 05:58 PM	#33
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by jatrax Can that be set in a user mode? Yes, that is the work-around. I can understand some of the frustration. This hidden feature of back-button focus has been popular for some users since the set-up and sequence was first described on this site some years ago. It allows the user to effectively toggle between the equivalents of AF-1 and AF-2 by simply changing the sequence of how two buttons are used with CIF being leveraged to trigger the shutter. The technique is hinted at in the user manuals, but not explicitly spelled out. Why it went away is a bit of a mystery, but then again so are other things like requiring conductive base on the lens to do CIF. Steve

04-04-2015, 06:44 PM	#34
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by kjpino Exactly! Why would they have BB Focus in the K3 suddenly ignore focus priority? Originally posted by stevebrot Perhaps because it is not that important to many users? OK...I just spent a half hour or so researching the K-5 features and playing the various settings of the K-3 and FINALLY caught the gist of the beef. It is the magical override of the focus priority to "off" if the AF button is set to AF-2. Yes, this is inconsistent. I would prefer that focus priority be retained for this case regardless of whether CIF is provided. For the "Cancel AF" setting, it would be nice if CIF was provided. After all, the viewfinder says "MF" and CIF is a feature of manual focus, but the current behavior is acceptable. Steve

04-04-2015, 10:22 PM	#35
jayman_1975 Veteran Member Join Date: Jun 2014 Posts: 385 Original Poster	I just noticed my new k5IIs will Fire the shutter regardless of focus status when focus priority is set to "only release shutter when focus is achieved". So maybe it's a firmware thing cause my old k5II wouldn't fire when not in focus. I wish I knew what firmware version that one had but I sold it awhile ago. I wonder if there's a way to find out what firmware version it had by using one of its pictures like the way you can check shutter count by uploading it to a website

04-04-2015, 11:42 PM	#36
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by jayman_1975 I wonder if there's a way to find out what firmware version it had by using one of its pictures like the way you can check shutter count by uploading it to a website The makernotes portion of the exif has the firmware version, though the file must be an in-camera JPEG or RAW from camera. Steve

04-12-2015, 05:12 PM	#37
bobbotron Site Supporter Join Date: Jan 2015 Location: Ottawa, ON Photos: Gallery Posts: 3,349	I've been caught by this a few times in action situations where I thought the focus was spot on, interesting to see BBAF is a possible solution to this. What does CIF stand for?

04-12-2015, 05:59 PM	#38
kjpino New Member Join Date: Nov 2010 Photos: Albums Posts: 18	Originally posted by bobbotron I've been caught by this a few times in action situations where I thought the focus was spot on, interesting to see BBAF is a possible solution to this. What does CIF stand for? ON the previous cameras BBAF would allow for this as BBAF could be used for CIF (Catch in Focus) - on the K3 it cannot - and that seems odd... Why would they take this option of that feature away? It means that if you use BBAF you can count on it for anything involving movement (kids, sports, wildlife, etc.)...

04-12-2015, 07:24 PM	#39
monochrome Loyal Site Supporter Join Date: Mar 2008 Location: Working From Home Photos: Gallery \| Albums Posts: 26,276	I wonder if it has anything to do with the improved tracking AF?

04-13-2015, 05:08 AM	#40
kjpino New Member Join Date: Nov 2010 Photos: Albums Posts: 18	It just makes me constantly have to switch auto focus settings in the menu - which is kind of a pain... especially after being so used to it on previous Pentax cameras and now having to retrain myself - and jumping from y K3 to my K7 and back is confusing since the BBAF works differently on each...