Remove aperture lever from K series lens = get M42 functionality?

**monochrome** · 08-15-2015, 05:35 PM

Originally posted by dcshooter

Ha, "galactic," eh? ! I'm sure it could be done, but in most cases it would likely be much easier to just scavenge one from a broken lens.

Eric tells me (accidental owner of a Canonista-eunuched K35/2) the aperture lever is unique to each lens model. The likelihood of finding a donor broken K35/2 is, well, not likely.

The stub of the protrusion is till there - only needs about 3/8" added back on (we should all be so lucky).

stevebrot · 08-17-2015, 02:19 PM

Originally posted by jkomp316

Do you see your automobile as a tool or an extension of your wardrobe?

??? I use my automobile for photography like everyone else.

Steve

fwcetus · 08-24-2015, 08:52 PM - **1 Like**

[EDIT: If you can't figure out the above series of images, what I am trying to show is that I picked up an already crippled K 135/2.5 lens, to see how it works (as if it were an M42 lens, using AV mode metering, similar to the original thrust of this thread), compared to how my original K 135/2.5 works (using M mode with green-button stop-down metering). Of course, the actual results should be approximately the same -- this is more of a test of convenience. But, in addition, to sort of paraphrase the words of the seller, I also hope to give the poor crippled K 135/2.5 a good home, where it can live out the rest of its life in dignity, as opposed to being stuck ingloriously on the snout of some god-awful Canon beast.]

**Digitalis** · 08-25-2015, 12:54 AM

Originally posted by dcshooter

Whether you approve of removing the aperture lever this way or not, I must say I'm appalled at the level of your dremeling skills.

I agree, you lack of finesse is appalling. Non destructive alteration of manual lenses is possible and the fact that you have not done this is equally appalling.

ZombieArmy · 08-25-2015, 01:22 AM

I find it funny how people are judging what others do with their own property. If I want to strip down a classic camera and paint it pink then damn it I will do so.

It's really none of your damn business.

That being said I dislike how AV mode works with m42 lenses as it is and generally just do everything manually.

IN BEFORE THE SHIT STORM

altopiet · 08-25-2015, 02:12 AM

Some are reversible, some not. My mint M50/1.4 was not, so a quick flick of the pliers did the job.

If you are not planing to resell the lens in the future, then why not change it, it's just a lens and I definitely do not worship camera lenses...

f8orbust · 08-25-2015, 12:46 PM

So this subject has reared its head again on the Forum. I remember contributing to this very same discussion some years back.

Just drill a little hole in the mount so that the lens locks before it locks into the original hole. This has the same effect as to not quite fully mounting the lens, but with a locking advantage. It works on AV very well. And if you wish to return the lens mount to an original state just pop a tiny bit of solder in the hole or replace the mount from an old broken lens.

Phil P

Just found the earlier discussion. Go to Articles at the top of the page, click on Members Submitted Articles, and then Pentax Len Articles. It's the first Sticky......How to use Manual/M42 lenses etc

Last edited by f8orbust; 08-25-2015 at 01:05 PM.

jkomp316 · 09-17-2015, 05:31 PM

Would the leverectomy also bypass a k30 or k50 aperature failure?

pathdoc · 09-18-2015, 04:30 AM

Originally posted by tromboads

I confess I snapped of a meter arm fro ma M 35mm f2.8 because the blades were not returning quickly.

Well if the aperture blades are stuffed anyway, there's nothing left to lose - it's useless as is, and you might as well convert it into a Takumar.

But that's a special case.

tromboads · 09-18-2015, 10:34 PM

:P I agree, better used then not.

that reminds me.

landstrykere · 03-11-2018, 05:56 PM

Originally posted by Fat Albert

The implication is that this is a destructive, irreversible process. Can't one just unscrew the lever?

well. I find this thread after I have been playing with my M42 lenses and thinking of using the K ones the same way. Curious about other experiences, so I revive the thread...

I have unscrew a bit of a cheap K lens and the non destructive lever removal or neutralization isn't trivial in this case. This may be common to many lenses...

the lever here is a part of a thick ring inserted on a ballbearing inside the K mount. So there's no unscrewing possible, if it is to removed, it must be cut off:

the ring on ballbearing has a longer lever inside the lens, that does release the diaphragm, and a spring keeps it full open otherwise (when the camera doesn't trigger the lever):

the notch inside the lens, where the internal lever releases/keep the diaphgram aperture:

as I see it, the lever can be neutralized by unscrewing the spring on the internal side of the mount (the spring holding the internal ring of the mount) but the long internal lever must be kept in order to keep a functional aperture ring. That's were it's not trivial...

I think I will just screw everything back on and let it like that. When I took the mount off, I wasn't careful enough, the aperture ring came off also and the small ballbearing doing the clicking stops jumped out somewhere. I had some old olympus lens around, that I have destroyed in order to extract ballbearings and springs; I started with screws but at a certain point had to use a hammer, well...

HelenJo · 03-11-2018, 10:14 PM

Originally posted by fwcetus

......................... But, in addition, to sort of paraphrase the words of the seller, I also hope to give the poor crippled K 135/2.5 a good home, where it can live out the rest of its life in dignity, as opposed to being stuck ingloriously on the snout of some god-awful Canon beast.]

ROFLOL ! This made me laugh until I nearly peed in my pants !

stevebrot · 03-12-2018, 10:03 AM

Originally posted by landstrykere

I have unscrew a bit of a cheap K lens and the non destructive lever removal or neutralization isn't trivial in this case. This may be common to many lenses...

Yes, a non-destructive conversion to manual aperture is usually not trivial for most lenses designed for open-aperture metering. The best-case outcome is that it works as desired and is reversible should one change their mind. More commonly, the aperture never works quite right afterward and parts are lost making reversion very difficult. I grimace a little as I type due to a fairly recent purchase of camera and lens (Exakta) where the lens was advertised as declicked for video, but fully functional with parts to revert. Neither was true.

As noted on the other thread, it is not clear why someone would want to do this given the ready availability of high quality modern and vintage lenses that feature manual aperture natively and may be nicely adapted to Pentax-K. Av mode metering is sort of cool in that one may simply dial down until the desired shutter speed is reached, but is unreliable outside of live view and even then not as good as green button. If one simply must have full manual aperture with a K-mount lens, purchase of a used Sony NEX and adapter will provide the full experience at a fairly low price point. If a dSLR is desired, a crop sensor Canon will also work. I personally prefer my vintage K-mount lenses over my M42 kit simply because I can avoid messing with the aperture ring every time I focus.

Steve

landstrykere · 03-12-2018, 10:21 PM

Originally posted by stevebrot

Yes, a non-destructive conversion to manual aperture is usually not trivial for most lenses designed for open-aperture metering. The best-case outcome is that it works as desired and is reversible should one change their mind. More commonly, the aperture never works quite right afterward and parts are lost making reversion very difficult.
As noted on the other thread, it is not clear why someone would want to do this given the ready availability of high quality modern and vintage lenses that feature manual aperture natively and may be nicely adapted to Pentax-K.

after some tries, yes, I totally agree it's not worth the time and risk. For me the reason to try was curiosity about a unified experience on both Spotmatic (or Zenit or old Praktica and such plain manual cameras) and the DSLR. Most of my lenses are M42, and I have a couple K ,so I just thought of maybe using these like the M42. But well it's a bit pointless. And I am not going no buy any more K lenses, just M42, so they can work on old film cameras.

08-24-2015, 08:52 PM - 1 Like	#48
fwcetus Site Supporter Join Date: Sep 2006 Location: New England Photos: Gallery \| Albums Posts: 1,286	[EDIT: If you can't figure out the above series of images, what I am trying to show is that I picked up an already crippled K 135/2.5 lens, to see how it works (as if it were an M42 lens, using AV mode metering, similar to the original thrust of this thread), compared to how my original K 135/2.5 works (using M mode with green-button stop-down metering). Of course, the actual results should be approximately the same -- this is more of a test of convenience. But, in addition, to sort of paraphrase the words of the seller, I also hope to give the poor crippled K 135/2.5 a good home, where it can live out the rest of its life in dignity, as opposed to being stuck ingloriously on the snout of some god-awful Canon beast.] Last edited by fwcetus; 08-25-2015 at 10:21 AM.

08-25-2015, 01:22 AM	#50
ZombieArmy Pentaxian Join Date: Jun 2014 Location: Florida Posts: 3,210	I find it funny how people are judging what others do with their own property. If I want to strip down a classic camera and paint it pink then damn it I will do so. It's really none of your damn business. That being said I dislike how AV mode works with m42 lenses as it is and generally just do everything manually. IN BEFORE THE SHIT STORM Last edited by ZombieArmy; 08-25-2015 at 01:32 AM.

03-11-2018, 10:14 PM	#57
HelenJo Forum Member Join Date: Feb 2018 Location: Sun City , Arizona. Posts: 72	Originally posted by fwcetus ......................... But, in addition, to sort of paraphrase the words of the seller, I also hope to give the poor crippled K 135/2.5 a good home, where it can live out the rest of its life in dignity, as opposed to being stuck ingloriously on the snout of some god-awful Canon beast.] ROFLOL ! This made me laugh until I nearly peed in my pants ! Last edited by HelenJo; 03-11-2018 at 10:21 PM.

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08-15-2015, 05:35 PM	#46
monochrome Loyal Site Supporter Join Date: Mar 2008 Location: Working From Home Photos: Gallery \| Albums Posts: 26,276	Originally posted by dcshooter Ha, "galactic," eh? ! I'm sure it could be done, but in most cases it would likely be much easier to just scavenge one from a broken lens. Eric tells me (accidental owner of a Canonista-eunuched K35/2) the aperture lever is unique to each lens model. The likelihood of finding a donor broken K35/2 is, well, not likely. The stub of the protrusion is till there - only needs about 3/8" added back on (we should all be so lucky).

08-17-2015, 02:19 PM	#47
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by jkomp316 Do you see your automobile as a tool or an extension of your wardrobe? ??? I use my automobile for photography like everyone else. Steve

08-25-2015, 12:54 AM	#49
Digitalis Site Supporter Join Date: Mar 2009 Location: Melbourne, Victoria Photos: Gallery Posts: 11,694	Originally posted by dcshooter Whether you approve of removing the aperture lever this way or not, I must say I'm appalled at the level of your dremeling skills. I agree, you lack of finesse is appalling. Non destructive alteration of manual lenses is possible and the fact that you have not done this is equally appalling.

08-25-2015, 02:12 AM	#51
altopiet Veteran Member Join Date: Sep 2010 Location: The Gem of the Karoo, South Africa Photos: Gallery \| Albums Posts: 2,307	Some are reversible, some not. My mint M50/1.4 was not, so a quick flick of the pliers did the job. If you are not planing to resell the lens in the future, then why not change it, it's just a lens and I definitely do not worship camera lenses...

08-25-2015, 12:46 PM	#52
f8orbust Junior Member Join Date: Feb 2009 Location: Greenwich, SE London, UK Posts: 36	So this subject has reared its head again on the Forum. I remember contributing to this very same discussion some years back. Just drill a little hole in the mount so that the lens locks before it locks into the original hole. This has the same effect as to not quite fully mounting the lens, but with a locking advantage. It works on AV very well. And if you wish to return the lens mount to an original state just pop a tiny bit of solder in the hole or replace the mount from an old broken lens. Phil P Just found the earlier discussion. Go to Articles at the top of the page, click on Members Submitted Articles, and then Pentax Len Articles. It's the first Sticky......How to use Manual/M42 lenses etc Last edited by f8orbust; 08-25-2015 at 01:05 PM.

09-17-2015, 05:31 PM	#53
jkomp316 Senior Member Join Date: Feb 2013 Photos: Gallery \| Albums Posts: 227	Would the leverectomy also bypass a k30 or k50 aperature failure?

09-18-2015, 04:30 AM	#54
pathdoc Pentaxian Join Date: Mar 2015 Photos: Gallery \| Albums Posts: 6,381	Originally posted by tromboads I confess I snapped of a meter arm fro ma M 35mm f2.8 because the blades were not returning quickly. Well if the aperture blades are stuffed anyway, there's nothing left to lose - it's useless as is, and you might as well convert it into a Takumar. But that's a special case.

09-18-2015, 10:34 PM	#55
tromboads Veteran Member Join Date: Apr 2012 Location: Melbs Photos: Gallery Posts: 1,240	:P I agree, better used then not. that reminds me.

03-11-2018, 05:56 PM	#56
landstrykere New Member Join Date: Nov 2017 Location: Nittedal Posts: 24	Originally posted by Fat Albert The implication is that this is a destructive, irreversible process. Can't one just unscrew the lever? well. I find this thread after I have been playing with my M42 lenses and thinking of using the K ones the same way. Curious about other experiences, so I revive the thread... I have unscrew a bit of a cheap K lens and the non destructive lever removal or neutralization isn't trivial in this case. This may be common to many lenses... the lever here is a part of a thick ring inserted on a ballbearing inside the K mount. So there's no unscrewing possible, if it is to removed, it must be cut off: the ring on ballbearing has a longer lever inside the lens, that does release the diaphragm, and a spring keeps it full open otherwise (when the camera doesn't trigger the lever): the notch inside the lens, where the internal lever releases/keep the diaphgram aperture: as I see it, the lever can be neutralized by unscrewing the spring on the internal side of the mount (the spring holding the internal ring of the mount) but the long internal lever must be kept in order to keep a functional aperture ring. That's were it's not trivial... I think I will just screw everything back on and let it like that. When I took the mount off, I wasn't careful enough, the aperture ring came off also and the small ballbearing doing the clicking stops jumped out somewhere. I had some old olympus lens around, that I have destroyed in order to extract ballbearings and springs; I started with screws but at a certain point had to use a hammer, well...

03-12-2018, 10:03 AM	#58
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by landstrykere I have unscrew a bit of a cheap K lens and the non destructive lever removal or neutralization isn't trivial in this case. This may be common to many lenses... Yes, a non-destructive conversion to manual aperture is usually not trivial for most lenses designed for open-aperture metering. The best-case outcome is that it works as desired and is reversible should one change their mind. More commonly, the aperture never works quite right afterward and parts are lost making reversion very difficult. I grimace a little as I type due to a fairly recent purchase of camera and lens (Exakta) where the lens was advertised as declicked for video, but fully functional with parts to revert. Neither was true. As noted on the other thread, it is not clear why someone would want to do this given the ready availability of high quality modern and vintage lenses that feature manual aperture natively and may be nicely adapted to Pentax-K. Av mode metering is sort of cool in that one may simply dial down until the desired shutter speed is reached, but is unreliable outside of live view and even then not as good as green button. If one simply must have full manual aperture with a K-mount lens, purchase of a used Sony NEX and adapter will provide the full experience at a fairly low price point. If a dSLR is desired, a crop sensor Canon will also work. I personally prefer my vintage K-mount lenses over my M42 kit simply because I can avoid messing with the aperture ring every time I focus. Steve

03-12-2018, 10:21 PM	#59
landstrykere New Member Join Date: Nov 2017 Location: Nittedal Posts: 24	Originally posted by stevebrot Yes, a non-destructive conversion to manual aperture is usually not trivial for most lenses designed for open-aperture metering. The best-case outcome is that it works as desired and is reversible should one change their mind. More commonly, the aperture never works quite right afterward and parts are lost making reversion very difficult. As noted on the other thread, it is not clear why someone would want to do this given the ready availability of high quality modern and vintage lenses that feature manual aperture natively and may be nicely adapted to Pentax-K. after some tries, yes, I totally agree it's not worth the time and risk. For me the reason to try was curiosity about a unified experience on both Spotmatic (or Zenit or old Praktica and such plain manual cameras) and the DSLR. Most of my lenses are M42, and I have a couple K ,so I just thought of maybe using these like the M42. But well it's a bit pointless. And I am not going no buy any more K lenses, just M42, so they can work on old film cameras.