should I have looked for a M mount/ K mount lens before I jumped into the m42 river?

enyaw · 10-12-2016, 07:10 PM

Hi, I've had issues with m42 adapters etc. before I noticed the option of having a lens aka manual focus with the native mount. "K/M" There is no right or wrong but out of simplicity. Should I have gone the latter route? They are both manual focus and 1 doesn't need an adapter. The prices are almost the same. Is there a diff optically?

Just wondering.

ps. the lens I'm talking about are 100mm and under

Adam · 10-12-2016, 08:16 PM

If you plan to use a lot of M42 lenses, go for the genuine Pentax adapter and you shouldn't have any issues. While manual K-mount lenses are generally more convenient (since you don't need an adapter), M42 lenses do allow you to shoot in Av mode thanks to their manual aperture diaphragm, which can speed up shooting a bit.

pathdoc · 10-13-2016, 03:41 AM

Originally posted by Adam

M42 lenses do allow you to shoot in Av mode thanks to their manual aperture diaphragm, which can speed up shooting a bit.

Against this, green button metering is open-aperture, is done with the press of a button, remains valid until the lighting conditions or the aperture settings change, and you can maintain a better focus. Stopping down an M42 lens can make things quite dark very quickly, depending on the ambient light.

enyaw · 10-13-2016, 03:12 PM

thanks for the input. Technically to use them it's the same. I'm going the manual route with the green button. It seems it's just the adapter I wasn't aware of. I only have (4) m42 mount lens. And I'm not buying anymore lol. The adapter is in transit but the native mount is way more convenient. Why would someone want to take the long way. If M42's were lying around your home I mean yeah. But in my case they weren't. I just got lucky at work and got 3 for $40 all primes. : )

Last edited by enyaw; 10-13-2016 at 03:32 PM.

pathdoc · 10-15-2016, 07:14 PM

Originally posted by enyaw

thanks for the input. Technically to use them it's the same. I'm going the manual route with the green button. It seems it's just the adapter I wasn't aware of. I only have (4) m42 mount lens. And I'm not buying anymore lol. The adapter is in transit but the native mount is way more convenient. Why would someone want to take the long way. If M42's were lying around your home I mean yeah. But in my case they weren't. I just got lucky at work and got 3 for $40 all primes. : )

With a windfall like that, the adapter is a no-brainer. Which lenses did you score?

enyaw · 10-16-2016, 04:42 AM

Hi, I got auto revuenon f 1.8 50mm, vivitar 28mm f 1.28 and vivitar 200mm f 1.35 auto telephoto all in excellent condition

**Lowell Goudge** · 10-16-2016, 07:14 AM

I think it depends upon what you intend to do long term.

I started into m42 lenses because I could not find a fast 35mm in k mount so I got a SMC Takumar 35/2 for $70. Having bought the adaptor, I began to find other m42 lenses quite cheap, typically $10-15 for lenses that actually were pretty good, like a tamron 28/2.5 and Helios 55/2. What clinched it for me was finding a super tak 85/1.9 in almost perfect condition at much less than the going market price.

Ultimately I decided to go for both a K mount and an M42 Kit. I took lenses that were different or unique for both kits. And while I have some very similar lenses in both k and m42 there are not too many.

Ultimately for M42 I started looking for preset lenses with round at all aperture diaphragms. The placement of the aperture usually behind the front element seems to give a significantly different bokeh to more modern lenses

enyaw · 10-16-2016, 11:04 AM

I might be heading down the same road. I have ordered the Pentax m42 mount adapter and will always have the other eye open for k mount at good prices. I'd like a 300mm prime for either but scared about the weight and manual focus until I get better at it

**Lowell Goudge** · 10-16-2016, 11:08 AM - **1 Like**

Originally posted by enyaw

I might be heading down the same road. I have ordered the pentax m42 mount and will always have the other eye open for k mount at good prices. I'd like a 300mm prime for either but scared about the weight and manual focus until I get better at it

My m42 300 is an nikkor H 300/4.5 retrofitted with a K mount , I use it as a manual aperture lens.

Got it for $20 because it was old. Actually I think it might be optically better than my K300/4

MF should not scare you. You just need to set it manually to about the middle of the focus range before putting your eye to the view finder

enyaw · 10-16-2016, 11:27 AM

it doesn't really scare me literally, I meant to say it's much faster on a 50mm prime : ) and the heavy weight. But in time I should get better at it and learn a trick or 2 like you just mentioned. Because I will be using it for wildlife mostly and those critters don't really give you a second chance lol. All while on a budget. I think manual focus is a good skill to learn anyways. There will be situations where you have to use it and the only way to get a shot. It also helps you to learn about the camera.

thank you,

pathdoc · 10-16-2016, 02:46 PM - **1 Like**

Originally posted by enyaw

Hi, I got auto revuenon f 1.8 50mm, vivitar 28mm f 1.28 and vivitar 200mm f 1.35 auto telephoto all in excellent condition

That's a pretty good combination to go shooting with. Plenty of people in the M42 era had a 28, a 50-ish of some description and something longer, often a 100 or a 135. 200 is a fair jump up, but not unheard of. Enjoy!

enyaw · 10-17-2016, 03:00 PM

Thanks pathdoc, for your input and encouragement. I'm just at the beginning of my journey. If it turns out manual focus and with these lens isn't a time consuming process. I may hunt for more lens esp. at the short end for landscapes and buildings that are really wide. I have 3 buildings/structures in mind already. I will enjoy as soon as I get the camera back I sent it in to get looked at. It had battery issues, but it's under warranty. And the m42 adapter isn't here yet either.

Btw, are you resident m42 expert/guru?

pathdoc · 10-19-2016, 07:50 AM - **1 Like**

Not an expert by any means, more an enthusiast who bought one M42 lens to see what the fuss was all about and didn't know where to stop... LOL. You will find many people on this site with much more experience than I have in M42 lenses.

The important thing is to be willing to make plenty of mistakes and spend a while learning. Fortunately with digital, this process is almost ridiculously simple and essentially free- the very short time between taking a picture and being able to see a result in great detail is perhaps the best thing about the DSLR revolution, possibly one of the most significant changes ever to happen to photography, as it closes the feedback loop in as close to zero time as makes no difference. I'm not sure the average non-developing user could ever hope for better than half an hour back in the day, and that's only if they were in immediate reach of a photo lab when they took the last shot and rewound the film.

enyaw · 10-19-2016, 04:33 PM

Ok, thanks again. But most of those people haven't chimed in. And you have. Means your very generous with your time and knowledge. Much appreciated

**TomB_tx** · 10-19-2016, 05:26 PM - **1 Like**

I started with the M42 lenses in 1965 with the meterless Pentax H1a. A friend who used Leica was amazed at the mechanical quality of my humble 55 f2.0 Super Takumar, and equally surprised at its sharpness. I think that the mechanical design and workmanship of the Asahi SuperTakumars and SMC Takumars was better than following generations, although later optics had improvements, not so much in sharpness but in overall image rendering.
I have quite a few SMC Pentax-M lenses that are also good mechanically, but the later -A lenses seem less well built, with more plastic in the operating rings that has worn over time.

10-12-2016, 07:10 PM	#1
enyaw Senior Member Join Date: Sep 2016 Posts: 276	should I have looked for a M mount/ K mount lens before I jumped into the m42 river? Hi, I've had issues with m42 adapters etc. before I noticed the option of having a lens aka manual focus with the native mount. "K/M" There is no right or wrong but out of simplicity. Should I have gone the latter route? They are both manual focus and 1 doesn't need an adapter. The prices are almost the same. Is there a diff optically? Just wondering. ps. the lens I'm talking about are 100mm and under

10-12-2016, 08:16 PM	#2
Adam Administrator Site Webmaster Join Date: Sep 2006 Location: Arizona Photos: Gallery \| Albums Posts: 51,595	If you plan to use a lot of M42 lenses, go for the genuine Pentax adapter and you shouldn't have any issues. While manual K-mount lenses are generally more convenient (since you don't need an adapter), M42 lenses do allow you to shoot in Av mode thanks to their manual aperture diaphragm, which can speed up shooting a bit. Adam PentaxForums.com Webmaster (Site Usage Guide \| Site Help \| My Photography) PentaxForums.com server and development costs are user-supported. You can help cover these costs by donating or purchasing one of our Pentax eBooks. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, KEH, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

10-16-2016, 11:04 AM	#8
enyaw Senior Member Join Date: Sep 2016 Posts: 276 Original Poster	I might be heading down the same road. I have ordered the Pentax m42 mount adapter and will always have the other eye open for k mount at good prices. I'd like a 300mm prime for either but scared about the weight and manual focus until I get better at it Last edited by enyaw; 10-16-2016 at 11:14 AM.

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10-13-2016, 03:41 AM	#3
pathdoc Pentaxian Join Date: Mar 2015 Photos: Gallery \| Albums Posts: 6,381	Originally posted by Adam M42 lenses do allow you to shoot in Av mode thanks to their manual aperture diaphragm, which can speed up shooting a bit. Against this, green button metering is open-aperture, is done with the press of a button, remains valid until the lighting conditions or the aperture settings change, and you can maintain a better focus. Stopping down an M42 lens can make things quite dark very quickly, depending on the ambient light.

10-13-2016, 03:12 PM	#4
enyaw Senior Member Join Date: Sep 2016 Posts: 276 Original Poster	thanks for the input. Technically to use them it's the same. I'm going the manual route with the green button. It seems it's just the adapter I wasn't aware of. I only have (4) m42 mount lens. And I'm not buying anymore lol. The adapter is in transit but the native mount is way more convenient. Why would someone want to take the long way. If M42's were lying around your home I mean yeah. But in my case they weren't. I just got lucky at work and got 3 for $40 all primes. : ) Last edited by enyaw; 10-13-2016 at 03:32 PM.

10-15-2016, 07:14 PM	#5
pathdoc Pentaxian Join Date: Mar 2015 Photos: Gallery \| Albums Posts: 6,381	Originally posted by enyaw thanks for the input. Technically to use them it's the same. I'm going the manual route with the green button. It seems it's just the adapter I wasn't aware of. I only have (4) m42 mount lens. And I'm not buying anymore lol. The adapter is in transit but the native mount is way more convenient. Why would someone want to take the long way. If M42's were lying around your home I mean yeah. But in my case they weren't. I just got lucky at work and got 3 for $40 all primes. : ) With a windfall like that, the adapter is a no-brainer. Which lenses did you score?

10-16-2016, 04:42 AM	#6
enyaw Senior Member Join Date: Sep 2016 Posts: 276 Original Poster	Hi, I got auto revuenon f 1.8 50mm, vivitar 28mm f 1.28 and vivitar 200mm f 1.35 auto telephoto all in excellent condition

10-16-2016, 07:14 AM	#7
Lowell Goudge Site Supporter Join Date: Jan 2007 Location: Toronto Photos: Gallery \| Albums Posts: 17,888	I think it depends upon what you intend to do long term. I started into m42 lenses because I could not find a fast 35mm in k mount so I got a SMC Takumar 35/2 for $70. Having bought the adaptor, I began to find other m42 lenses quite cheap, typically $10-15 for lenses that actually were pretty good, like a tamron 28/2.5 and Helios 55/2. What clinched it for me was finding a super tak 85/1.9 in almost perfect condition at much less than the going market price. Ultimately I decided to go for both a K mount and an M42 Kit. I took lenses that were different or unique for both kits. And while I have some very similar lenses in both k and m42 there are not too many. Ultimately for M42 I started looking for preset lenses with round at all aperture diaphragms. The placement of the aperture usually behind the front element seems to give a significantly different bokeh to more modern lenses

10-16-2016, 11:08 AM - 1 Like	#9
Lowell Goudge Site Supporter Join Date: Jan 2007 Location: Toronto Photos: Gallery \| Albums Posts: 17,888	Originally posted by enyaw I might be heading down the same road. I have ordered the pentax m42 mount and will always have the other eye open for k mount at good prices. I'd like a 300mm prime for either but scared about the weight and manual focus until I get better at it My m42 300 is an nikkor H 300/4.5 retrofitted with a K mount , I use it as a manual aperture lens. Got it for $20 because it was old. Actually I think it might be optically better than my K300/4 MF should not scare you. You just need to set it manually to about the middle of the focus range before putting your eye to the view finder

10-16-2016, 11:27 AM	#10
enyaw Senior Member Join Date: Sep 2016 Posts: 276 Original Poster	it doesn't really scare me literally, I meant to say it's much faster on a 50mm prime : ) and the heavy weight. But in time I should get better at it and learn a trick or 2 like you just mentioned. Because I will be using it for wildlife mostly and those critters don't really give you a second chance lol. All while on a budget. I think manual focus is a good skill to learn anyways. There will be situations where you have to use it and the only way to get a shot. It also helps you to learn about the camera. thank you,

10-16-2016, 02:46 PM - 1 Like	#11
pathdoc Pentaxian Join Date: Mar 2015 Photos: Gallery \| Albums Posts: 6,381	Originally posted by enyaw Hi, I got auto revuenon f 1.8 50mm, vivitar 28mm f 1.28 and vivitar 200mm f 1.35 auto telephoto all in excellent condition That's a pretty good combination to go shooting with. Plenty of people in the M42 era had a 28, a 50-ish of some description and something longer, often a 100 or a 135. 200 is a fair jump up, but not unheard of. Enjoy!

10-17-2016, 03:00 PM	#12
enyaw Senior Member Join Date: Sep 2016 Posts: 276 Original Poster	Thanks pathdoc, for your input and encouragement. I'm just at the beginning of my journey. If it turns out manual focus and with these lens isn't a time consuming process. I may hunt for more lens esp. at the short end for landscapes and buildings that are really wide. I have 3 buildings/structures in mind already. I will enjoy as soon as I get the camera back I sent it in to get looked at. It had battery issues, but it's under warranty. And the m42 adapter isn't here yet either. Btw, are you resident m42 expert/guru?

10-19-2016, 07:50 AM - 1 Like	#13
pathdoc Pentaxian Join Date: Mar 2015 Photos: Gallery \| Albums Posts: 6,381	Not an expert by any means, more an enthusiast who bought one M42 lens to see what the fuss was all about and didn't know where to stop... LOL. You will find many people on this site with much more experience than I have in M42 lenses. The important thing is to be willing to make plenty of mistakes and spend a while learning. Fortunately with digital, this process is almost ridiculously simple and essentially free- the very short time between taking a picture and being able to see a result in great detail is perhaps the best thing about the DSLR revolution, possibly one of the most significant changes ever to happen to photography, as it closes the feedback loop in as close to zero time as makes no difference. I'm not sure the average non-developing user could ever hope for better than half an hour back in the day, and that's only if they were in immediate reach of a photo lab when they took the last shot and rewound the film.

10-19-2016, 04:33 PM	#14
enyaw Senior Member Join Date: Sep 2016 Posts: 276 Original Poster	Ok, thanks again. But most of those people haven't chimed in. And you have. Means your very generous with your time and knowledge. Much appreciated

10-19-2016, 05:26 PM - 1 Like	#15
TomB_tx Loyal Site Supporter Join Date: Jun 2011 Location: Texas Photos: Gallery Posts: 1,446	I started with the M42 lenses in 1965 with the meterless Pentax H1a. A friend who used Leica was amazed at the mechanical quality of my humble 55 f2.0 Super Takumar, and equally surprised at its sharpness. I think that the mechanical design and workmanship of the Asahi SuperTakumars and SMC Takumars was better than following generations, although later optics had improvements, not so much in sharpness but in overall image rendering. I have quite a few SMC Pentax-M lenses that are also good mechanically, but the later -A lenses seem less well built, with more plastic in the operating rings that has worn over time.