K-1 won't control Aperture for D-FA lens (15-30mm f2.8, 24-70mm f2.8)

Dashuai322 · 01-28-2023, 04:25 PM

Having my K-1 since its first release, never have any issues. Recently I have noticed I always got some over exposure photos when I use AV mode to shoot. So I took some time to dig into my equipment then I found my camera seems not controlling aperture on all my D FA lenses, which is 15-30mm f2.8 and 24-70mm f2.8. I shoot three photos on each lens with f2.8, f8 and f22, and all other settings are the same on M mode, and the pictures from these two lens are equally exposed and I could see the lens are focusing well too. But when I switched it to other lens I have, FA 43MM F1.9, FA 50MM F1.4, FA 77MM 1.8 and a sigma 70-200 f2.8, three photos on each lens showing dramatically exposure difference. I tried to clean all my contact points and updated my wireframe on K-1, the result are same. I was wondering if anyone had this problem before, or what could be possible cause for this issue? Thanks in advance!

**UncleVanya** · 01-28-2023, 05:45 PM

Wireframe? Maybe this is a typo for firmware? The two lenses in question are both Tamron designs - that’s the only thing I can think of besides both being d fa lenses that is common to them both. I know that isn’t much help.

Not a Number · 01-28-2023, 08:52 PM

Do any of the lenses have aperture rings? Are they all set on the "A" setting?

Dashuai322 · 01-28-2023, 09:51 PM

Originally posted by UncleVanya

Wireframe? Maybe this is a typo for firmware? The two lenses in question are both Tamron designs - that’s the only thing I can think of besides both being d fa lenses that is common to them both. I know that isn’t much help.

Thanks for the info, I thought the same thing, so I updated the wireframe today, the test result are the same. Seems there are not so much information about this issue anywhere online.

---------- Post added 01-28-23 at 11:53 PM ----------

Originally posted by Not a Number

Do any of the lenses have aperture rings? Are they all set on the "A" setting?

Thanks for the reply, both lenses do not have "A" settings, I could change F value on the camera, but the lens won't do anything, they all keep stay on F 2.8

**luftfluss** · 01-28-2023, 10:14 PM

Originally posted by Dashuai322

Thanks for the info, I thought the same thing, so I updated the wireframe today, the test result are the same. Seems there are not so much information about this issue anywhere online.

Firmware is the word, not wireframe.

Dashuai322 · 01-28-2023, 10:25 PM

I did find the issue on both lenses. Seem like the aperture lever on both lens are not operating well. The one on 15-30 is getting sticky, once I pull it all the way open, it won't get back to its original position, however if I am pulling it half way it will get back to its original position, maybe need a new spring? The 24-70mm one works as it should, but it won't trigger the aperture blade, and the blade stay open all the time.

---------- Post added 01-29-23 at 12:27 AM ----------

Oh I see, thanks for the correction!

---------- Post added 01-29-23 at 12:27 AM ----------

Originally posted by luftfluss

Firmware is the word, not wireframe.

Oh I see, thanks for the correction!

biz-engineer · 01-28-2023, 11:24 PM

I experienced first frame over exposure (completely blown up) recently with the 15-30, original K1 (2016) ~80K clicks, although exposure parameters in exif were correct. But this also happened a few times , randomly , with other lenses, in the first couple of years I used the camera, it happened more recently. Exposures get back to normal after the first exposure. I don't know what could have caused overexposure. Aperture block failure? Sticky blades? Initial position of lens hardware after the lens is mounted on the camera? Happened with any lens, not only with the 15-30. Not a bit deal, I delete the shot and take another one; would be more annoying if I was in a situation shooting professionally.

Dashuai322 · 01-28-2023, 11:39 PM - **3 Likes**

Originally posted by biz-engineer

I experienced first frame over exposure (completely blown up) recently with the 15-30, original K1 (2016) ~80K clicks, although exposure parameters in exif were correct. But this also happened a few times , randomly , with other lenses, in the first couple of years I used the camera, it happened more recently. Exposures get back to normal after the first exposure. I don't know what could have caused overexposure. Aperture block failure? Sticky blades? Initial position of lens hardware after the lens is mounted on the camera? Happened with any lens, not only with the 15-30. Not a bit deal, I delete the shot and take another one; would be more annoying if I was in a situation shooting professionally.

Thanks for the reply, yeah I have found the issue. I have been not using those lenses for a while, the 15-30mm lever is getting dirty and 24-70mm lever is not engage in the right place. I quickly opened them up while watching some repair videos, and it only took me like 40 minutes to clean and reset the lever and both lenses are working now. Cheers!!

**mikesbike** · 01-28-2023, 11:50 PM

I have a number of DFA lenses, but none of them are Tamron designs. Some of them are many years old, and only used on occasion. Yet I have never experienced any problem when engaging their usage, even if they sat for a few years!

Glad you found the cause of this problem and were able to fix it without needing service! I will keep your experience in mind in case I encounter the same issue!

**Mikesul** · 01-29-2023, 08:39 AM

Congratulations on finding the problems. Kudos for doing the repairs yourself!

Dashuai322 · 01-29-2023, 08:58 AM

Originally posted by mikesbike

I have a number of DFA lenses, but none of them are Tamron designs. Some of them are many years old, and only used on occasion. Yet I have never experienced any problem when engaging their usage, even if they sat for a few years!

Glad you found the cause of this problem and were able to fix it without needing service! I will keep your experience in mind in case I encounter the same issue!

Yeah, my older lenses all working well too, that is pretty interesting to see these newer lens got the problems first.

---------- Post added 01-29-23 at 10:59 AM ----------

Originally posted by Mikesul

Congratulations on finding the problems. Kudos for doing the repairs yourself!

Thanks, I was a little nervous before I doing it, but it is a simple repair!

biz-engineer · 01-29-2023, 09:54 AM

Originally posted by Dashuai322

I quickly opened them up while watching some repair videos, and it only took me like 40 minutes to clean and reset the lever and both lenses are working now.

Where did you find repair examples? Could you point to those resources?

Dashuai322 · 01-29-2023, 01:09 PM

Originally posted by biz-engineer

Where did you find repair examples? Could you point to those resources?

Here are the resources for opening 24-70mm lens

You Tube

and this one is for what could be the cause

The Complete Guide to Fixing Sticky Aperture Blades ? Clever Creations

biz-engineer · 01-30-2023, 05:11 AM

Originally posted by Dashuai322

Here are the resources for opening 24-70mm lens

Ok, complete disassembly, I won't do it.

Dashuai322 · 01-30-2023, 08:00 PM - **1 Like**

Originally posted by biz-engineer

Ok, complete disassembly, I won't do it.

I would not do all the way like that too. but mine only requires to remove the mount ring. So I think I was lucky that there were no other issues

01-28-2023, 04:25 PM	#1
Dashuai322 New Member Join Date: Apr 2013 Location: Cleveland, OH Posts: 19	K-1 won't control Aperture for D-FA lens (15-30mm f2.8, 24-70mm f2.8) Having my K-1 since its first release, never have any issues. Recently I have noticed I always got some over exposure photos when I use AV mode to shoot. So I took some time to dig into my equipment then I found my camera seems not controlling aperture on all my D FA lenses, which is 15-30mm f2.8 and 24-70mm f2.8. I shoot three photos on each lens with f2.8, f8 and f22, and all other settings are the same on M mode, and the pictures from these two lens are equally exposed and I could see the lens are focusing well too. But when I switched it to other lens I have, FA 43MM F1.9, FA 50MM F1.4, FA 77MM 1.8 and a sigma 70-200 f2.8, three photos on each lens showing dramatically exposure difference. I tried to clean all my contact points and updated my wireframe on K-1, the result are same. I was wondering if anyone had this problem before, or what could be possible cause for this issue? Thanks in advance!

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01-28-2023, 05:45 PM	#2
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,472	Wireframe? Maybe this is a typo for firmware? The two lenses in question are both Tamron designs - that’s the only thing I can think of besides both being d fa lenses that is common to them both. I know that isn’t much help.

01-28-2023, 08:52 PM	#3
Not a Number Moderator Join Date: Mar 2012 Location: Venice, CA Posts: 10,526	Do any of the lenses have aperture rings? Are they all set on the "A" setting?

01-28-2023, 09:51 PM	#4
Dashuai322 New Member Join Date: Apr 2013 Location: Cleveland, OH Posts: 19 Original Poster	Originally posted by UncleVanya Wireframe? Maybe this is a typo for firmware? The two lenses in question are both Tamron designs - that’s the only thing I can think of besides both being d fa lenses that is common to them both. I know that isn’t much help. Thanks for the info, I thought the same thing, so I updated the wireframe today, the test result are the same. Seems there are not so much information about this issue anywhere online. ---------- Post added 01-28-23 at 11:53 PM ---------- Originally posted by Not a Number Do any of the lenses have aperture rings? Are they all set on the "A" setting? Thanks for the reply, both lenses do not have "A" settings, I could change F value on the camera, but the lens won't do anything, they all keep stay on F 2.8

01-28-2023, 10:14 PM	#5
luftfluss Site Supporter Join Date: Jun 2011 Location: NJ Photos: Gallery \| Albums Posts: 11,629	Originally posted by Dashuai322 Thanks for the info, I thought the same thing, so I updated the wireframe today, the test result are the same. Seems there are not so much information about this issue anywhere online. Firmware is the word, not wireframe.

01-28-2023, 10:25 PM	#6
Dashuai322 New Member Join Date: Apr 2013 Location: Cleveland, OH Posts: 19 Original Poster	I did find the issue on both lenses. Seem like the aperture lever on both lens are not operating well. The one on 15-30 is getting sticky, once I pull it all the way open, it won't get back to its original position, however if I am pulling it half way it will get back to its original position, maybe need a new spring? The 24-70mm one works as it should, but it won't trigger the aperture blade, and the blade stay open all the time. ---------- Post added 01-29-23 at 12:27 AM ---------- Oh I see, thanks for the correction! ---------- Post added 01-29-23 at 12:27 AM ---------- Originally posted by luftfluss Firmware is the word, not wireframe. Oh I see, thanks for the correction!

01-28-2023, 11:24 PM	#7
biz-engineer Pentaxian Join Date: Feb 2015 Photos: Gallery Posts: 12,252	I experienced first frame over exposure (completely blown up) recently with the 15-30, original K1 (2016) ~80K clicks, although exposure parameters in exif were correct. But this also happened a few times , randomly , with other lenses, in the first couple of years I used the camera, it happened more recently. Exposures get back to normal after the first exposure. I don't know what could have caused overexposure. Aperture block failure? Sticky blades? Initial position of lens hardware after the lens is mounted on the camera? Happened with any lens, not only with the 15-30. Not a bit deal, I delete the shot and take another one; would be more annoying if I was in a situation shooting professionally.

01-28-2023, 11:39 PM - 3 Likes	#8
Dashuai322 New Member Join Date: Apr 2013 Location: Cleveland, OH Posts: 19 Original Poster	Originally posted by biz-engineer I experienced first frame over exposure (completely blown up) recently with the 15-30, original K1 (2016) ~80K clicks, although exposure parameters in exif were correct. But this also happened a few times , randomly , with other lenses, in the first couple of years I used the camera, it happened more recently. Exposures get back to normal after the first exposure. I don't know what could have caused overexposure. Aperture block failure? Sticky blades? Initial position of lens hardware after the lens is mounted on the camera? Happened with any lens, not only with the 15-30. Not a bit deal, I delete the shot and take another one; would be more annoying if I was in a situation shooting professionally. Thanks for the reply, yeah I have found the issue. I have been not using those lenses for a while, the 15-30mm lever is getting dirty and 24-70mm lever is not engage in the right place. I quickly opened them up while watching some repair videos, and it only took me like 40 minutes to clean and reset the lever and both lenses are working now. Cheers!!

01-28-2023, 11:50 PM	#9
mikesbike Site Supporter Join Date: Dec 2016 Location: Southeastern Michigan Posts: 4,566	I have a number of DFA lenses, but none of them are Tamron designs. Some of them are many years old, and only used on occasion. Yet I have never experienced any problem when engaging their usage, even if they sat for a few years! Glad you found the cause of this problem and were able to fix it without needing service! I will keep your experience in mind in case I encounter the same issue!

01-29-2023, 08:39 AM	#10
Mikesul Loyal Site Supporter Join Date: Sep 2009 Location: Phoenix, AZ Posts: 7,594	Congratulations on finding the problems. Kudos for doing the repairs yourself!

01-29-2023, 08:58 AM	#11
Dashuai322 New Member Join Date: Apr 2013 Location: Cleveland, OH Posts: 19 Original Poster	Originally posted by mikesbike I have a number of DFA lenses, but none of them are Tamron designs. Some of them are many years old, and only used on occasion. Yet I have never experienced any problem when engaging their usage, even if they sat for a few years! Glad you found the cause of this problem and were able to fix it without needing service! I will keep your experience in mind in case I encounter the same issue! Yeah, my older lenses all working well too, that is pretty interesting to see these newer lens got the problems first. ---------- Post added 01-29-23 at 10:59 AM ---------- Originally posted by Mikesul Congratulations on finding the problems. Kudos for doing the repairs yourself! Thanks, I was a little nervous before I doing it, but it is a simple repair!

01-29-2023, 09:54 AM	#12
biz-engineer Pentaxian Join Date: Feb 2015 Photos: Gallery Posts: 12,252	Originally posted by Dashuai322 I quickly opened them up while watching some repair videos, and it only took me like 40 minutes to clean and reset the lever and both lenses are working now. Where did you find repair examples? Could you point to those resources?

01-30-2023, 05:11 AM	#14
biz-engineer Pentaxian Join Date: Feb 2015 Photos: Gallery Posts: 12,252	Originally posted by Dashuai322 Here are the resources for opening 24-70mm lens Ok, complete disassembly, I won't do it.

01-30-2023, 08:00 PM - 1 Like	#15
Dashuai322 New Member Join Date: Apr 2013 Location: Cleveland, OH Posts: 19 Original Poster	Originally posted by biz-engineer Ok, complete disassembly, I won't do it. I would not do all the way like that too. but mine only requires to remove the mount ring. So I think I was lucky that there were no other issues