DFA 150-450 and 9 point AF failure on K3

RobG · 10-16-2017, 03:22 AM

I've had the DFA 150-450 for a while now, always using it with centre point AF. On the weekend, I decided to try 9 point auto AF on the K3. The lens almost immediately went to minimum focal distance and stayed there. I thought that using the focus limiter might have been the issue (in some contradictory way) but today I tried again with the lens set to full range rather than 6m-infinity and had the same result. Has anyone else experienced issues on the K3 with the DFA 150-450 and 9 point AF?

PS I have the latest firmware on the camera (1.30) which was kindly installed by the Ricoh attendant in Shinjuku, Tokyo.

audiobomber · 10-16-2017, 06:14 AM

Auto AF is garbage. Try Expanded Area AF.

RobG · 10-16-2017, 06:18 PM

Originally posted by audiobomber

Auto AF is garbage. Try Expanded Area AF.

OK, but any AF mode should work, rather than going to minimum focus and staying there refusing to move.

**Canada_Rockies** · 10-16-2017, 10:38 PM

If the AF is "auto" as in select the area, it will almost invariably select the closest point with any contrast to it. That option invariably gives me indigestion, not to mention out of focus images.

RobG · 10-16-2017, 11:23 PM

Originally posted by Canada_Rockies

If the AF is "auto" as in select the area, it will almost invariably select the closest point with any contrast to it. That option invariably gives me indigestion, not to mention out of focus images.

OK, but have you tried the 9 point auto AF option from the interface accessed on the K3 using the "Info" button with the DFA 150-450? When I do, the lens goes to minimum focal distance and stays there. I'm not just talking about being out of focus because the camera picks the wrong AF point. The subject I was using this on was a plane that almost filled the viewfinder in bright sunlight. Not a low contrast scene. If the lens was hunting, I would have been less concerned. It's not hunting. It's not playing at all.

RobG · 10-17-2017, 03:53 AM

If anyone with a DFA 150-450 and K3 could try the setting and let me know if you have any issues, it would be greatly appreciated!

G and T · 10-17-2017, 04:05 AM

My K3 and D FA 150-450 play nicely together on all settings including 9 point AF.
Could you possibly have the lenses AF limit switch set outside the distance needed for the scene?

Glenn

**clickclick** · 10-17-2017, 09:32 AM

Just tested my K3II and D FA 150-450 in 9 point AF mode, and no issues.

Have you double checked the focus mode switch, as well as all the other focus related switches to make sure one isn't in a partial engagement etc.?

RobG · 10-17-2017, 03:32 PM

Originally posted by G and T

My K3 and D FA 150-450 play nicely together on all settings including 9 point AF.
Could you possibly have the lenses AF limit switch set outside the distance needed for the scene?

The first time, the lens was set to focus limiting 6m-infinity and I was photographing aircraft in flight, so it should have been appropriate. The second time, I turned off the focus limiting and had the same result - lens went to minimum focus and stayed there. What firmware does your camera have, please?

---------- Post added 18-10-17 at 09:36 AM ----------

Originally posted by clickclick

Just tested my K3II and D FA 150-450 in 9 point AF mode, and no issues.

Thanks! I'll have to experiment more to see if I can identify what triggers the issue. The K3II is a slightly different camera with different firmware, so it may not have the same bug, but thanks for responding!

Quote:

Have you double checked the focus mode switch, as well as all the other focus related switches to make sure one isn't in a partial engagement etc.?

Good point. I'll double check - although I have no problem as soon as I set the AF to centre spot.

**clickclick** · 10-18-2017, 04:19 AM

Originally posted by RobG

[snip]

Thanks! I'll have to experiment more to see if I can identify what triggers the issue. The K3II is a slightly different camera with different firmware, so it may not have the same bug, but thanks for responding!

Good point. I'll double check - although I have no problem as soon as I set the AF to centre spot.

Yep, a bit different, but since you were being flooded with responses, I figured it couldn't helpt but to throw it out there.

Hope it turns out to just be some odd combination of switch setting/something not seated etc. Have you made sure the electrical contacts on the lens and body are all happy too? Just thinking out loud without enough coffee yet, but hopefully it'll be something simple like that.

bdery · 10-18-2017, 05:22 AM

Originally posted by RobG

If anyone with a DFA 150-450 and K3 could try the setting and let me know if you have any issues, it would be greatly appreciated!

I did try this when I was testing the lens last winter, on a K-3 and K-1. The behaviour you describe did not occur.

are there objects close to you in the FOV? Try maybe to shoot at only distant objects, with nothing close, and see what happens. Otherwise, change the camera's batteries and see how it works, sometimes with larger lenses when batteries are low AF behaves strangely.

RobG · 10-18-2017, 02:27 PM

Originally posted by clickclick

Yep, a bit different, but since you were being flooded with responses, I figured it couldn't helpt but to throw it out there.

Hope it turns out to just be some odd combination of switch setting/something not seated etc. Have you made sure the electrical contacts on the lens and body are all happy too? Just thinking out loud without enough coffee yet, but hopefully it'll be something simple like that.

Since the lens behaves normally when on centre spot AF, I doubt that the contacts are involved. I also haven't had similar behaviour with any other lens.

Originally posted by bdery

I did try this when I was testing the lens last winter, on a K-3 and K-1. The behaviour you describe did not occur. are there objects close to you in the FOV? Try maybe to shoot at only distant objects, with nothing close, and see what happens. Otherwise, change the camera's batteries and see how it works, sometimes with larger lenses when batteries are low AF behaves strangely.

The battery was fully charged at the time when this first occurred, but thanks for the suggestion. The camera also works fine on centre spot AF. I'll have to try to experiment more. As I mentioned, the key behaviour that was concerning was that the lens went to minimum focus and stayed there, not responding at all to repeatedly half depressing the shutter release, and despite there being a high contrast subject in the field of view.

RobG · 10-18-2017, 07:42 PM

OK, the problem may have been a PEBCAK. The focus limiter has the ranges as: full, 2-6 then 6-infinity, which isn't a very logical progression. I suspect that I may have accidentally put the lens on 2-6m when I meant to have it on 6-infinity. However, more testing needed.

RobG · 10-19-2017, 05:56 PM

I just experimented a bit more. Low contrast does seem to be a problem, but only in Auto 9 point AF. There's a reasonable variety of detail in the clouds today, but Auto 9 point AF complete fails to lock on any of it, while centre point is fine, and manual select 9 point AF is fine. So the Auto 9 point AF issue isn't entirely a PEBCAK. It does seem to work OK on higher contrast subjects - trees on hills, buildings, but not clouds.

**clickclick** · 10-19-2017, 06:57 PM

So, good news! It's nice to know I'm not the only one who can do this (type of thing)....

The different modes are definitely worth trying to see what works best under different conditions.

And I actually find the sequence quite logical - think of full range as the limiter being set to 0 (off), and then the following ranges are a natural progression.

10-16-2017, 03:22 AM	#1
RobG Otis Memorial Pentaxian Join Date: Dec 2009 Location: Canberra Photos: Gallery \| Albums Posts: 8,905	DFA 150-450 and 9 point AF failure on K3 I've had the DFA 150-450 for a while now, always using it with centre point AF. On the weekend, I decided to try 9 point auto AF on the K3. The lens almost immediately went to minimum focal distance and stayed there. I thought that using the focus limiter might have been the issue (in some contradictory way) but today I tried again with the lens set to full range rather than 6m-infinity and had the same result. Has anyone else experienced issues on the K3 with the DFA 150-450 and 9 point AF? PS I have the latest firmware on the camera (1.30) which was kindly installed by the Ricoh attendant in Shinjuku, Tokyo.

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10-16-2017, 06:14 AM	#2
audiobomber Veteran Member Join Date: May 2008 Location: Sudbury, Ontario Photos: Albums Posts: 6,806	Auto AF is garbage. Try Expanded Area AF.

10-16-2017, 06:18 PM	#3
RobG Otis Memorial Pentaxian Join Date: Dec 2009 Location: Canberra Photos: Gallery \| Albums Posts: 8,905 Original Poster	Originally posted by audiobomber Auto AF is garbage. Try Expanded Area AF. OK, but any AF mode should work, rather than going to minimum focus and staying there refusing to move.

10-16-2017, 10:38 PM	#4
Canada_Rockies Loyal Site Supporter Join Date: Nov 2007 Location: Sparwood, BC, Canada Photos: Gallery \| Albums Posts: 12,385	If the AF is "auto" as in select the area, it will almost invariably select the closest point with any contrast to it. That option invariably gives me indigestion, not to mention out of focus images.

10-16-2017, 11:23 PM	#5
RobG Otis Memorial Pentaxian Join Date: Dec 2009 Location: Canberra Photos: Gallery \| Albums Posts: 8,905 Original Poster	Originally posted by Canada_Rockies If the AF is "auto" as in select the area, it will almost invariably select the closest point with any contrast to it. That option invariably gives me indigestion, not to mention out of focus images. OK, but have you tried the 9 point auto AF option from the interface accessed on the K3 using the "Info" button with the DFA 150-450? When I do, the lens goes to minimum focal distance and stays there. I'm not just talking about being out of focus because the camera picks the wrong AF point. The subject I was using this on was a plane that almost filled the viewfinder in bright sunlight. Not a low contrast scene. If the lens was hunting, I would have been less concerned. It's not hunting. It's not playing at all.

10-17-2017, 03:53 AM	#6
RobG Otis Memorial Pentaxian Join Date: Dec 2009 Location: Canberra Photos: Gallery \| Albums Posts: 8,905 Original Poster	If anyone with a DFA 150-450 and K3 could try the setting and let me know if you have any issues, it would be greatly appreciated!

10-17-2017, 04:05 AM	#7
G and T Veteran Member Join Date: Aug 2011 Location: Langwarrin Australia Photos: Gallery Posts: 382	My K3 and D FA 150-450 play nicely together on all settings including 9 point AF. Could you possibly have the lenses AF limit switch set outside the distance needed for the scene? Glenn

10-17-2017, 09:32 AM	#8
clickclick Loyal Site Supporter Join Date: May 2016 Location: East Coast Posts: 2,904	Just tested my K3II and D FA 150-450 in 9 point AF mode, and no issues. Have you double checked the focus mode switch, as well as all the other focus related switches to make sure one isn't in a partial engagement etc.?

10-17-2017, 03:32 PM	#9
RobG Otis Memorial Pentaxian Join Date: Dec 2009 Location: Canberra Photos: Gallery \| Albums Posts: 8,905 Original Poster	Originally posted by G and T My K3 and D FA 150-450 play nicely together on all settings including 9 point AF. Could you possibly have the lenses AF limit switch set outside the distance needed for the scene? The first time, the lens was set to focus limiting 6m-infinity and I was photographing aircraft in flight, so it should have been appropriate. The second time, I turned off the focus limiting and had the same result - lens went to minimum focus and stayed there. What firmware does your camera have, please? ---------- Post added 18-10-17 at 09:36 AM ---------- Originally posted by clickclick Just tested my K3II and D FA 150-450 in 9 point AF mode, and no issues. Thanks! I'll have to experiment more to see if I can identify what triggers the issue. The K3II is a slightly different camera with different firmware, so it may not have the same bug, but thanks for responding! Quote: Have you double checked the focus mode switch, as well as all the other focus related switches to make sure one isn't in a partial engagement etc.? Good point. I'll double check - although I have no problem as soon as I set the AF to centre spot.

10-18-2017, 04:19 AM	#10
clickclick Loyal Site Supporter Join Date: May 2016 Location: East Coast Posts: 2,904	Originally posted by RobG [snip] Thanks! I'll have to experiment more to see if I can identify what triggers the issue. The K3II is a slightly different camera with different firmware, so it may not have the same bug, but thanks for responding! Good point. I'll double check - although I have no problem as soon as I set the AF to centre spot. Yep, a bit different, but since you were being flooded with responses, I figured it couldn't helpt but to throw it out there. Hope it turns out to just be some odd combination of switch setting/something not seated etc. Have you made sure the electrical contacts on the lens and body are all happy too? Just thinking out loud without enough coffee yet, but hopefully it'll be something simple like that.

10-18-2017, 05:22 AM	#11
bdery Pentaxian Join Date: Mar 2008 Location: Quebec city, Canada Photos: Gallery Posts: 9,362	Originally posted by RobG If anyone with a DFA 150-450 and K3 could try the setting and let me know if you have any issues, it would be greatly appreciated! I did try this when I was testing the lens last winter, on a K-3 and K-1. The behaviour you describe did not occur. are there objects close to you in the FOV? Try maybe to shoot at only distant objects, with nothing close, and see what happens. Otherwise, change the camera's batteries and see how it works, sometimes with larger lenses when batteries are low AF behaves strangely.

10-18-2017, 02:27 PM	#12
RobG Otis Memorial Pentaxian Join Date: Dec 2009 Location: Canberra Photos: Gallery \| Albums Posts: 8,905 Original Poster	Originally posted by clickclick Yep, a bit different, but since you were being flooded with responses, I figured it couldn't helpt but to throw it out there. Hope it turns out to just be some odd combination of switch setting/something not seated etc. Have you made sure the electrical contacts on the lens and body are all happy too? Just thinking out loud without enough coffee yet, but hopefully it'll be something simple like that. Since the lens behaves normally when on centre spot AF, I doubt that the contacts are involved. I also haven't had similar behaviour with any other lens. Originally posted by bdery I did try this when I was testing the lens last winter, on a K-3 and K-1. The behaviour you describe did not occur. are there objects close to you in the FOV? Try maybe to shoot at only distant objects, with nothing close, and see what happens. Otherwise, change the camera's batteries and see how it works, sometimes with larger lenses when batteries are low AF behaves strangely. The battery was fully charged at the time when this first occurred, but thanks for the suggestion. The camera also works fine on centre spot AF. I'll have to try to experiment more. As I mentioned, the key behaviour that was concerning was that the lens went to minimum focus and stayed there, not responding at all to repeatedly half depressing the shutter release, and despite there being a high contrast subject in the field of view.

10-18-2017, 07:42 PM	#13
RobG Otis Memorial Pentaxian Join Date: Dec 2009 Location: Canberra Photos: Gallery \| Albums Posts: 8,905 Original Poster	OK, the problem may have been a PEBCAK. The focus limiter has the ranges as: full, 2-6 then 6-infinity, which isn't a very logical progression. I suspect that I may have accidentally put the lens on 2-6m when I meant to have it on 6-infinity. However, more testing needed.

10-19-2017, 05:56 PM	#14
RobG Otis Memorial Pentaxian Join Date: Dec 2009 Location: Canberra Photos: Gallery \| Albums Posts: 8,905 Original Poster	I just experimented a bit more. Low contrast does seem to be a problem, but only in Auto 9 point AF. There's a reasonable variety of detail in the clouds today, but Auto 9 point AF complete fails to lock on any of it, while centre point is fine, and manual select 9 point AF is fine. So the Auto 9 point AF issue isn't entirely a PEBCAK. It does seem to work OK on higher contrast subjects - trees on hills, buildings, but not clouds.

10-19-2017, 06:57 PM	#15
clickclick Loyal Site Supporter Join Date: May 2016 Location: East Coast Posts: 2,904	So, good news! It's nice to know I'm not the only one who can do this (type of thing).... The different modes are definitely worth trying to see what works best under different conditions. And I actually find the sequence quite logical - think of full range as the limiter being set to 0 (off), and then the following ranges are a natural progression.