I need an M42 "permanent" adapter

old4570 · 12-23-2014, 05:29 AM

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M42 adapters for K mount ..
There are two I know off , Chinese and the Pentax made one ..
I always thought they were designed to go into the body , and so convert the body to M42 , rather than convert a lens from M42 to K mount .
The Pentax one is so much nicer than the Chinese version ..

Certainly remove the spring clip and notch the adapter if converting a lens rather than a body ..

vonBaloney · 12-23-2014, 09:10 AM

Originally posted by old4570

M42 adapters for K mount ..
There are two I know off , Chinese and the Pentax made one ..

Probably many manufacturers of the cheap ones -- it seems to be a crap shoot how good they are, even if you get them from the same supplier after some time has passed. (I've had ones where the threads were off and the lenses all mounted upside down when screwed-in.)

Quote:

I always thought they were designed to go into the body , and so convert the body to M42 , rather than convert a lens from M42 to K mount .

Yes, they are designed to stay in the body, thus the spring clip.

Quote:

The Pentax one is so much nicer than the Chinese version ..

...and if you are going to use it in the body, get the Pentax one. Anyone who has more than a couple m42s should have at least one genuine Pentax version, and will probably end up with many cheap ones (plus at least one non-infinity one, which also come in handy).

Quote:

Certainly remove the spring clip and notch the adapter if converting a lens rather than a body ..

The cheap ones basically don't work in the body unless you only use m42 lenses -- if you don't remove the spring clip and put it in there, you WILL be spending the afternoon trying to the remove the damn thing from your camera. So the cheap ones are really only good for attaching to the lens as far as I'm concerned. The notch would have to go on the lens itself (right?) not the adapter, so it is a permanent and technically damaging alteration of the lens...

ajzimmerman · 01-15-2015, 02:08 PM

I bought this one, will it work for focusing M42 lenses to infinity?
GENUINE M42 LENS TO PENTAX K MOUNT ADAPTER ORIGINAL FOR INFINITY JAPAN

vonBaloney · 01-15-2015, 02:27 PM - **1 Like**

Yes. But I don't think it is genuine Pentax, so you probably overpaid there. But maybe it is. (The lettering is different that I've seen on the real ones, but then again they have been making them for decades so there are variants.) And if it is a genuine Pentax, it is not really suitable for leaving on the lens because the real ones have a looser fit (in the camera body) and you need to leave the spring on. What I would do as a test is remove the spring first thing, mount an m42 lens with it (one with "base" like a Takumar, not a tapering one like some German and Russian m42's have) and see how tight it is when mounted. If it has a tight friction fit, it is a third-party version and I'd use it just like that (never put the spring back). If it is loosey-goosey with a lot of rotational play when mounted, it is probably a real Pentax and you should put the spring back which will lock it into the camera body and then you screw and unscrew the m42 lens just like you had an actual m42 camera (this is the way you're supposed to use it). And then to get it out you use a fingernail or a pen to press the spring down and rotate, which shouldn't be too hard. (If it is a third-party version with the spring still in, this part is extremely difficult and frustrating, which is why you remove it in that case.)

ajzimmerman · 01-15-2015, 02:32 PM

Originally posted by vonBaloney

Yes. But I don't think it is genuine Pentax, so you probably overpaid there. But maybe it is. (The lettering is different that I've seen on the real ones, but then again they have been making them for decades so there are variants.) And if it is a genuine Pentax, it is not really suitable for leaving on the lens because the real ones have a looser fit (in the camera body) and you need to leave the spring on. What I would do as a test is remove the spring first thing, mount an m42 lens with it (one with "base" like a Takumar, not a tapering one like some German and Russian m42's have) and see how tight it is when mounted. If it has a tight friction fit, it is a third-party version and I'd use it just like that (never put the spring back). If it is loosey-goosey with a lot of rotational play when mounted, it is probably a real Pentax and you should put the spring back which will lock it into the camera body and then you screw and unscrew the m42 lens just like you had an actual m42 camera (this is the way you're supposed to use it). And then to get it out you use a fingernail or a pen to press the spring down and rotate, which shouldn't be too hard. (If it is a third-party version with the spring still in, this part is extremely difficult and frustrating, which is why you remove it in that case.)

Thanks for letting me know, I will follow your advise.

Wild Mark · 01-15-2015, 03:02 PM

Originally posted by ajzimmerman

I bought this one, will it work for focusing M42 lenses to infinity?
GENUINE M42 LENS TO PENTAX K MOUNT ADAPTER ORIGINAL FOR INFINITY JAPAN

Definitely third party adapter - NOT GENUINE.

The genuine has ASAHI - PENTAX or PENTAX written on it with JAPAN written on the opposite side of the ring. Usually the genuine ring has black paint on the mirror box side too, presumably to dampen light reflections - another benefit of genuine.

Yes, genuine is a looser fit making it far easier to install and remove. You do not need the 'tool' that often comes with the non-genuine adapters to install/ remove.

And yes again I concur with others here when they say the non-genuine adapter can get stuck and cause immense grief. It has happened once to me and will not happen ever again. Genuine adapters all the way.

Caveat to last comment - I am prepared to use non genuine as permanent fixtures to M42 lenses with the spring removed.

ajzimmerman · 01-15-2015, 03:10 PM

Originally posted by Wild Mark

Definitely third party adapter - NOT GENUINE.

The genuine has ASAHI - PENTAX or PENTAX written on it with JAPAN written on the opposite side of the ring. Usually the genuine ring has black paint on the mirror box side too, presumably to dampen light reflections - another benefit of genuine.

Ok I'll try and cancel it.

vonBaloney · 01-15-2015, 03:11 PM

Originally posted by Wild Mark

Definitely third party adapter - NOT GENUINE.

The genuine has ASAHI - PENTAX or PENTAX written on it with JAPAN written on the opposite side of the ring. Usually the genuine ring has black paint on the mirror box side too, presumably to dampen light reflections - another benefit of genuine.

Some newer ones have PHILIPPINES instead of JAPAN.

Looking at that ebay listing now I see also that the spring is on the wrong side vs genuine. Genuine has the spring at 10 o'clock, PENTAX at 12, the other gap at 4, and the country at 6. So yeah, definitely not genuine. Remove that spring.

ajzimmerman · 01-15-2015, 03:17 PM

Originally posted by vonBaloney

Some newer ones have PHILIPPINES instead of JAPAN.

Looking at that ebay listing now I see also that the spring is on the wrong side vs genuine. Genuine has the spring at 10 o'clock, PENTAX at 12, the other gap at 4, and the country at 6. So yeah, definitely not genuine. Remove that spring.

How's this one?
Mint Original Pentax 30120 K Body Mount Ring Adapter to M42 Lens for Infinity | eBay

vonBaloney · 01-15-2015, 03:41 PM

Originally posted by ajzimmerman

How's this one?
Mint Original Pentax 30120 K Body Mount Ring Adapter to M42 Lens for Infinity | eBay

Yeah, that's the real deal. I'm not knocking the third-party ones (as long as the lens ends up right-side up when screwed in, not always the case) -- if you want one to leave on the lens then they are better. Genuine ones stay on the body as long as needed. Anyone who uses more than a few m42s will want at least one genuine and probably numerous third-party ones (including at least one non-infinity with the flange). They all have their uses. I have 2 genuine and a dozen or so others myself...

ajzimmerman · 01-15-2015, 04:13 PM

Originally posted by vonBaloney

Yeah, that's the real deal. I'm not knocking the third-party ones (as long as the lens ends up right-side up when screwed in, not always the case) -- if you want one to leave on the lens then they are better. Genuine ones stay on the body as long as needed. Anyone who uses more than a few m42s will want at least one genuine and probably numerous third-party ones (including at least one non-infinity with the flange). They all have their uses. I have 2 genuine and a dozen or so others myself...

The guy refunded me, so I'll buy that genuine one.

vonBaloney · 01-15-2015, 05:27 PM

Originally posted by ajzimmerman

The guy refunded me, so I'll buy that genuine one.

For third-party ones, I use the ebay seller "roxsen" (hong kong) -- they are about $8 each I think.

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12-23-2014, 05:29 AM	#16
old4570 Veteran Member Join Date: Feb 2013 Location: Melbourne Photos: Albums Posts: 2,551	Staff note: This post may contain affiliate links, which means Pentax Forums may earn a small commission if a visitor clicks through and makes a purchase. If you would like to support the forum directly, you may also make a donation here. M42 adapters for K mount .. There are two I know off , Chinese and the Pentax made one .. I always thought they were designed to go into the body , and so convert the body to M42 , rather than convert a lens from M42 to K mount . The Pentax one is so much nicer than the Chinese version .. Certainly remove the spring clip and notch the adapter if converting a lens rather than a body ..

12-23-2014, 09:10 AM	#17
vonBaloney Pentaxian Join Date: Oct 2011 Location: Albuquerque, NM Posts: 6,029	Originally posted by old4570 M42 adapters for K mount .. There are two I know off , Chinese and the Pentax made one .. Probably many manufacturers of the cheap ones -- it seems to be a crap shoot how good they are, even if you get them from the same supplier after some time has passed. (I've had ones where the threads were off and the lenses all mounted upside down when screwed-in.) Quote: I always thought they were designed to go into the body , and so convert the body to M42 , rather than convert a lens from M42 to K mount . Yes, they are designed to stay in the body, thus the spring clip. Quote: The Pentax one is so much nicer than the Chinese version .. ...and if you are going to use it in the body, get the Pentax one. Anyone who has more than a couple m42s should have at least one genuine Pentax version, and will probably end up with many cheap ones (plus at least one non-infinity one, which also come in handy). Quote: Certainly remove the spring clip and notch the adapter if converting a lens rather than a body .. The cheap ones basically don't work in the body unless you only use m42 lenses -- if you don't remove the spring clip and put it in there, you WILL be spending the afternoon trying to the remove the damn thing from your camera. So the cheap ones are really only good for attaching to the lens as far as I'm concerned. The notch would have to go on the lens itself (right?) not the adapter, so it is a permanent and technically damaging alteration of the lens...

01-15-2015, 02:08 PM	#18
ajzimmerman Junior Member Join Date: Oct 2012 Location: Richmond Posts: 48	I bought this one, will it work for focusing M42 lenses to infinity? GENUINE M42 LENS TO PENTAX K MOUNT ADAPTER ORIGINAL FOR INFINITY JAPAN

01-15-2015, 02:27 PM - 1 Like	#19
vonBaloney Pentaxian Join Date: Oct 2011 Location: Albuquerque, NM Posts: 6,029	Yes. But I don't think it is genuine Pentax, so you probably overpaid there. But maybe it is. (The lettering is different that I've seen on the real ones, but then again they have been making them for decades so there are variants.) And if it is a genuine Pentax, it is not really suitable for leaving on the lens because the real ones have a looser fit (in the camera body) and you need to leave the spring on. What I would do as a test is remove the spring first thing, mount an m42 lens with it (one with "base" like a Takumar, not a tapering one like some German and Russian m42's have) and see how tight it is when mounted. If it has a tight friction fit, it is a third-party version and I'd use it just like that (never put the spring back). If it is loosey-goosey with a lot of rotational play when mounted, it is probably a real Pentax and you should put the spring back which will lock it into the camera body and then you screw and unscrew the m42 lens just like you had an actual m42 camera (this is the way you're supposed to use it). And then to get it out you use a fingernail or a pen to press the spring down and rotate, which shouldn't be too hard. (If it is a third-party version with the spring still in, this part is extremely difficult and frustrating, which is why you remove it in that case.)

01-15-2015, 02:32 PM	#20
ajzimmerman Junior Member Join Date: Oct 2012 Location: Richmond Posts: 48	Originally posted by vonBaloney Yes. But I don't think it is genuine Pentax, so you probably overpaid there. But maybe it is. (The lettering is different that I've seen on the real ones, but then again they have been making them for decades so there are variants.) And if it is a genuine Pentax, it is not really suitable for leaving on the lens because the real ones have a looser fit (in the camera body) and you need to leave the spring on. What I would do as a test is remove the spring first thing, mount an m42 lens with it (one with "base" like a Takumar, not a tapering one like some German and Russian m42's have) and see how tight it is when mounted. If it has a tight friction fit, it is a third-party version and I'd use it just like that (never put the spring back). If it is loosey-goosey with a lot of rotational play when mounted, it is probably a real Pentax and you should put the spring back which will lock it into the camera body and then you screw and unscrew the m42 lens just like you had an actual m42 camera (this is the way you're supposed to use it). And then to get it out you use a fingernail or a pen to press the spring down and rotate, which shouldn't be too hard. (If it is a third-party version with the spring still in, this part is extremely difficult and frustrating, which is why you remove it in that case.) Thanks for letting me know, I will follow your advise.

01-15-2015, 03:02 PM	#21
Wild Mark Veteran Member Join Date: Jun 2013 Location: Newcastle Photos: Gallery \| Albums Posts: 1,954	Originally posted by ajzimmerman I bought this one, will it work for focusing M42 lenses to infinity? GENUINE M42 LENS TO PENTAX K MOUNT ADAPTER ORIGINAL FOR INFINITY JAPAN Definitely third party adapter - NOT GENUINE. The genuine has ASAHI - PENTAX or PENTAX written on it with JAPAN written on the opposite side of the ring. Usually the genuine ring has black paint on the mirror box side too, presumably to dampen light reflections - another benefit of genuine. Yes, genuine is a looser fit making it far easier to install and remove. You do not need the 'tool' that often comes with the non-genuine adapters to install/ remove. And yes again I concur with others here when they say the non-genuine adapter can get stuck and cause immense grief. It has happened once to me and will not happen ever again. Genuine adapters all the way. Caveat to last comment - I am prepared to use non genuine as permanent fixtures to M42 lenses with the spring removed.

01-15-2015, 03:10 PM	#22
ajzimmerman Junior Member Join Date: Oct 2012 Location: Richmond Posts: 48	Originally posted by Wild Mark Definitely third party adapter - NOT GENUINE. The genuine has ASAHI - PENTAX or PENTAX written on it with JAPAN written on the opposite side of the ring. Usually the genuine ring has black paint on the mirror box side too, presumably to dampen light reflections - another benefit of genuine. Ok I'll try and cancel it.

01-15-2015, 03:11 PM	#23
vonBaloney Pentaxian Join Date: Oct 2011 Location: Albuquerque, NM Posts: 6,029	Originally posted by Wild Mark Definitely third party adapter - NOT GENUINE. The genuine has ASAHI - PENTAX or PENTAX written on it with JAPAN written on the opposite side of the ring. Usually the genuine ring has black paint on the mirror box side too, presumably to dampen light reflections - another benefit of genuine. Some newer ones have PHILIPPINES instead of JAPAN. Looking at that ebay listing now I see also that the spring is on the wrong side vs genuine. Genuine has the spring at 10 o'clock, PENTAX at 12, the other gap at 4, and the country at 6. So yeah, definitely not genuine. Remove that spring.

01-15-2015, 03:17 PM	#24
ajzimmerman Junior Member Join Date: Oct 2012 Location: Richmond Posts: 48	Originally posted by vonBaloney Some newer ones have PHILIPPINES instead of JAPAN. Looking at that ebay listing now I see also that the spring is on the wrong side vs genuine. Genuine has the spring at 10 o'clock, PENTAX at 12, the other gap at 4, and the country at 6. So yeah, definitely not genuine. Remove that spring. How's this one? Mint Original Pentax 30120 K Body Mount Ring Adapter to M42 Lens for Infinity \| eBay

01-15-2015, 03:41 PM	#25
vonBaloney Pentaxian Join Date: Oct 2011 Location: Albuquerque, NM Posts: 6,029	Originally posted by ajzimmerman How's this one? Mint Original Pentax 30120 K Body Mount Ring Adapter to M42 Lens for Infinity \| eBay Yeah, that's the real deal. I'm not knocking the third-party ones (as long as the lens ends up right-side up when screwed in, not always the case) -- if you want one to leave on the lens then they are better. Genuine ones stay on the body as long as needed. Anyone who uses more than a few m42s will want at least one genuine and probably numerous third-party ones (including at least one non-infinity with the flange). They all have their uses. I have 2 genuine and a dozen or so others myself...

01-15-2015, 04:13 PM	#26
ajzimmerman Junior Member Join Date: Oct 2012 Location: Richmond Posts: 48	Originally posted by vonBaloney Yeah, that's the real deal. I'm not knocking the third-party ones (as long as the lens ends up right-side up when screwed in, not always the case) -- if you want one to leave on the lens then they are better. Genuine ones stay on the body as long as needed. Anyone who uses more than a few m42s will want at least one genuine and probably numerous third-party ones (including at least one non-infinity with the flange). They all have their uses. I have 2 genuine and a dozen or so others myself... The guy refunded me, so I'll buy that genuine one.

01-15-2015, 05:27 PM	#27
vonBaloney Pentaxian Join Date: Oct 2011 Location: Albuquerque, NM Posts: 6,029	Originally posted by ajzimmerman The guy refunded me, so I'll buy that genuine one. For third-party ones, I use the ebay seller "roxsen" (hong kong) -- they are about $8 each I think.