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12-06-2018, 06:39 AM   #1
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Shake Reduction stuck, or???

Went for a drive with the wife when it was still very nice weather here a while back, and took a few shots.



The 1st: https://app.box.com/s/421hrw8gnmza0x1pb3rcvgrvsj5sufwh

The 7th: https://app.box.com/s/pnufm4633qi57pzqifb9vp0abemnff7r

The 6th: https://app.box.com/s/t68zkkmv22zun05cih2z64poqyjr3bk5

The 2nd-5th were similar to the 6th, showing varying degrees of impossible shake or movement.

BTW, the first six shots also show very low contrast, and I'm assuming this is due to the position of the sun which was pointing towards me from over the roof.

I am sure that the blurriness is not due to any motion. Is this the Shake Reduction misbehaving? Is the sun screwing upthing? Is there another explanation?


Last edited by bxf; 12-06-2018 at 06:58 AM. Reason: Links screwed up...
12-06-2018, 07:07 AM   #2
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What is the exif info? It’s not attached to the image and would likely have the answers. Also, what camera / lens you were using would help.
12-06-2018, 07:18 AM   #3
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EXIF is there if you download it:
K3 v1.4

34mm f4 @ ISO100 1/180s, Pattern metering, Auto WB
12-06-2018, 08:38 AM   #4
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QuoteOriginally posted by twilhelm Quote
What is the exif info? Itís not attached to the image and would likely have the answers. Also, what camera / lens you were using would help.
QuoteOriginally posted by Docrwm Quote
EXIF is there if you download it:
K3 v1.4

34mm f4 @ ISO100 1/180s, Pattern metering, Auto WB
Yes, EXIF should be there, but anyway, it's a K-3 (hence the K-s forum), and a16-85mm lens, which has been very pleasing for the most part.

12-06-2018, 08:43 AM   #5
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I am not seeing blur in the middle photo (7th), just underexposure.

Tha last one may be out of focus and affected by the glare. Difficult to tell without full size image.

At 1/180 at the focal length you are using the SR will be having no effect.
12-06-2018, 09:39 AM   #6
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You could try some tripod shots using 2 sec self timer or just disable SR and shoot a few more shots without sunlight flare. I'm wondering if flare confused the AF sensor. Live view is another option to try in similar conditions.
12-06-2018, 09:55 AM   #7
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QuoteOriginally posted by pschlute Quote
I am not seeing blur in the middle photo (7th), just underexposure.
The middle one was included to show that the problem suddenly disappeared. It is not blurred. i.e. The 1st and 7th are "OK", but 2-6 are obviously bad.


QuoteOriginally posted by pschlute Quote
Tha last one may be out of focus and affected by the glare. Difficult to tell without full size image.
You should be able to use the + sign at the bottom expand the image as much as you want. Also, a download should yield full size. There is obvious motion in at least some of the 2-6 images, if not all. I also wonder if the glare is a factor here.


QuoteOriginally posted by pschlute Quote
At 1/180 at the focal length you are using the SR will be having no effect.

My SR is ON most of the time. I don't necessarily expect it to do anything when it does not need to. But I don't know that it is completely deactivated at the indicated shutter speed, and if it is not, and it is misbehaving then that could be my problem, I suppose.

---------- Post added 06-12-18 at 16:57 ----------

QuoteOriginally posted by UncleVanya Quote
You could try some tripod shots using 2 sec self timer or just disable SR and shoot a few more shots without sunlight flare. I'm wondering if flare confused the AF sensor. Live view is another option to try in similar conditions.
Pretty much the shots after the 6th were OK, insofar as the shown problem is concerned. I doubt that I could replicate the situation.
12-06-2018, 10:07 AM   #8
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QuoteOriginally posted by bxf Quote
Pretty much the shots after the 6th were OK, insofar as the shown problem is concerned. I doubt that I could replicate the situation.
I would suggest gently cleaning the AF sensor if you see the problem again - and maybe shielding the lens by hand if the problem pops up again to see if that resolves the problem. If those don't then turn off SR and try again just to eliminate it. I would lean towards flare induced AF confusion more than SR. When I have seen SR problems documented on images it has been at lower speeds and or really messy smear with totally wonky movement. Those SR problems were persistent and could not be turned off - the SR system was just badly messed up. Very rare. I have not seen this present in person - just images shared.

12-06-2018, 10:43 AM   #9
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I just noticed that one has to download the image to see it in its original form. Expanding the on-screen image using the + sign is not the same, as the detail is gone.

The downloaded image clearly shows motion blur: look at the sunglasses and shoes.
12-06-2018, 11:08 AM   #10
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How were you focussing? AF or manual ?
12-06-2018, 01:52 PM   #11
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@bxf
In picture #6 the sign on right top (which is nearer) looks sharper than everything else.
So I guess it is not shake reduction, but AF failure.

I see one main difference in your settings: only for #6 you used flash, and this was mirrored by the window in the background.
Is it possible you did not wait till the AF had locked?

@pschlute
According to EXIF, AF was spot with matrix measurement. #6 with fill flash, the others without.

Last edited by RKKS08; 12-06-2018 at 02:32 PM. Reason: typing
12-06-2018, 02:17 PM   #12
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QuoteOriginally posted by RKKS08 Quote
According to EXIF, AF was spot
I think that is the problem. The picture is out of focus. The spot AF sensor cannot see anything to focus on and i suspect stopped trying at minimum focus distance
12-06-2018, 04:34 PM   #13
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QuoteOriginally posted by pschlute Quote
How were you focussing? AF or manual ?
AF, center point and recompose, but very little movement of camera for the recompose, definitely not enough to create such a problem, even if it is a focusing issue.


QuoteOriginally posted by RKKS08 Quote
@bxf
In picture #6 the sign on right top (which is nearer) looks sharper than everything else.
So I guess it is not shake reduction, but AF failure.
Interesting observation, but could a "simple" AF failure result in quadrupling the frame of the sunglasses?

QuoteOriginally posted by RKKS08 Quote
I see one main difference in your settings: only for #6 you used flash, and this was mirrored by the window in the background.
Is it possible you did not wait till the AF had locked?
Images 2-6 are all similarly bad. Of those, two were with flash and three without.

I cannot eliminate the possibility that I failed to wait for the AF to lock. Unfortunately, the AFPointInFocus field in the metadata is not filled when the camera is set to back button focus (instead of shutter release focus). Of the total 104 shots taken that day, in addition to shots 2-6 there was only one similarly bad one.

QuoteOriginally posted by pschlute Quote
I think that is the problem. The picture is out of focus. The spot AF sensor cannot see anything to focus on and i suspect stopped trying at minimum focus distance
Well, if bad misfocusing can create the appearance of multiple images (as is the case with the sunglasses), then I suppose it can be simpy a case of me not waiting for AF confirmation. But five shots in a row, with only one more out of the following 98 makes me wonder.
5 Days Ago - 2 Likes   #14
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QuoteOriginally posted by bxf Quote
Unfortunately, the AFPointInFocus field in the metadata is not filled when the camera is set to back button focus (instead of shutter release focus).
If you are using the camera set up with the AF button you need to hold in the AF button until you press the shutter release. If you release the AF button prior to shutter release the camera will not register the AF point in focus in the metadata. You probably won't lose focus but it will not register. It took me quite a while to figure that one out a few years back.
4 Days Ago   #15
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QuoteOriginally posted by Larrymc Quote
If you are using the camera set up with the AF button you need to hold in the AF button until you press the shutter release. If you release the AF button prior to shutter release the camera will not register the AF point in focus in the metadata. You probably won't lose focus but it will not register. It took me quite a while to figure that one out a few years back.
I had a thread about this problem a long time ago, and "we" felt it was a bug. Nobody offered the solution you present here. Very good to know!

And no, you don't lose focus if you release the back button before you shoot, because pressing the shutter release has no effect on AF, and there is nothing else that will cause the lens to refocus.
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