120mm- M vs K

**MXLX** · 06-23-2020, 04:00 PM

Okay-- as a starting point, I don't need a 120mm lens. But if'n I was to pick one (and yes, I've read the reviews), do I go with the size and reputation of the K version, or the compactness and integrated hood of the M? Opinions and arguments in both directions appreciated and encouraged.

**Riggomatic** · 06-23-2020, 05:17 PM - **5 Likes**

I have the K version. I agree with the reviews that the K is a sharp lens. I get great results (my opinion

) at all stops. Colors are on the warmer side (my opinion) which I really like.
I still use it every so often, but bought for indoor High School band performance pictures. Which worked well for me at f2.8.

I don't think you would be disappointed with the K, even if you don't need it.

A few examples

At f2.8

At f4

At f8

Wasp · 06-24-2020, 08:34 AM - **2 Likes**

This is a tough call. Both are pretty good and the difference is likely to be subtle. The "big" difference lies in the recipe for SMC which changed, meaning that colors are a little different. The K is slightly warmer AFAIK.

My answer would depend on what you already have. I am taking the completionist stance on this. If you already have a bunch of M lenses, get another M. And vice versa.

This one was made with my K 135mm f/3.5. It was my only K lens when I got it. The rest of my collection are mostly M series. That bothered my inner completionist no end until I got hold of a K 50mm f/1.2, but I feel slightly better now. I do feel the need for the K 85mm f/1.8 and one of the K 35mm lenses (not picky about aperture). Maybe a 24mm too. See where this goes?

glasbak · 06-24-2020, 09:15 AM - **2 Likes**

Although I did not test these against each other, I expect the behavior to be like most K versus M lenses : K better image over the whole 24x36 frame, the M good in the centre, less in the edges/corners.

**MXLX** · 06-24-2020, 10:54 AM - **1 Like**

I understand "completionist." I'm happy that I'm not at home to see where the gaps in the K collection are... Knowing the availables led to a buncha Takumars...

**iheiramo** · 06-24-2020, 11:47 AM

I have no experience with K lenses, so can't do comparison between models. I have the M120 and I think the reviews don't do it justice. I have almost all M primes and I found 120 to be the best tele in series, if we consider M*300 as supertele and M85 as portrait lens.

I just shot a month with it in Single In Challenge: SIC 2020 05 Pentax M120/2.8 FF | Flickr

**MXLX** · 06-24-2020, 02:24 PM

^^^^^
Yeah, it's probably your fine work in the SIC that started the problem/search for me in the first place.

**Riggomatic** · 06-24-2020, 03:43 PM

Originally posted by Wasp

This is a tough call. Both are pretty good and the difference is likely to be subtle. The "big" difference lies in the recipe for SMC which changed, meaning that colors are a little different. The K is slightly warmer AFAIK.

My answer would depend on what you already have. I am taking the completionist stance on this. If you already have a bunch of M lenses, get another M. And vice versa.

This one was made with my K 135mm f/3.5. It was my only K lens when I got it. The rest of my collection are mostly M series. That bothered my inner completionist no end until I got hold of a K 50mm f/1.2, but I feel slightly better now. I do feel the need for the K 85mm f/1.8 and one of the K 35mm lenses (not picky about aperture). Maybe a 24mm too. See where this goes?

I started with the K 135mm f3.5 as well... I've added: 24mm f2.8-- 30mm f2.8-- 35mm f3.5-- 50mm f1.4-- 85mm f1.8-- 105mm f2.8-- 120mm f2.8-- 135mm f2.5-- 200mm f4-- 300mm f4.
A 35mm f2 will be arriving in a couple days to add to my collection

. (Still waiting on a 50mm f1.2 deal and 200mm f2.5)

Sticking with the same series K or M will also reduce your filter collection as well ( If a polarizer or ND is used).

**MXLX** · 06-24-2020, 03:58 PM - **1 Like**

I have the 300/4 from the film days. On the lookout for a 24/2.8.
200/2.5? Dadgummit.
--
Okay, looked up the cost of that one...I'm good.

Back to the 120...

**iheiramo** · 06-24-2020, 11:05 PM

Originally posted by MXLX

^^^^^
Yeah, it's probably your fine work in the SIC that started the problem/search for me in the first place.

Sorry, didn't mean to

Since you have mostly K series I might stick with that.

Wasp · 06-25-2020, 04:47 AM

I forgot that I have a K 200mm f/2.5. The looks of it is more like the M series than the K. The lettering around the barrel, I mean.

Jonathan Mac · 06-25-2020, 07:00 AM

I would doubt there's a huge difference between them optically. The M is very nice and not that common, I've never seen a K for sale so they must be very rare indeed. I suppose in the K series it had to compete with the 135/2.5 which is superb (better than the M 120) so fewer were produced.

I bought mine to replace the M 135/3.5 as a compact telephoto lens for travel (even on digital) as the more modern, slow zooms weren't cutting it in the image quality department. The M 135mm was better in that regard but the 120mm is better still, plus faster and a little shorter, which is better in most situations (180mm equivalent instead of 200mm equivalent).

**MXLX** · 06-25-2020, 07:19 AM

@Riggomatic--I had looked at your pics several times before I saw the "baseball" in the last one.

**MXLX** · 06-25-2020, 05:24 PM - **1 Like**

Thanks for the info, all. I happened upon a K 120 for a price well below the average in the reviews. On its way.

**TwoUptons** · 06-25-2020, 05:50 PM - **1 Like**

Good choice. I have the Takumar, and it's my favorite M42 tele...

-Eric

06-23-2020, 04:00 PM	#1
MXLX Loyal Site Supporter Join Date: Apr 2019 Location: Western NC Photos: Albums Posts: 834	120mm- M vs K Okay-- as a starting point, I don't *need* a 120mm lens. But if'n I was to pick one (and yes, I've read the reviews), do I go with the size and reputation of the K version, or the compactness and integrated hood of the M? Opinions and arguments in both directions appreciated and encouraged.

06-23-2020, 05:17 PM - 5 Likes	#2
Riggomatic Loyal Site Supporter Join Date: Nov 2014 Location: Auburn, Indiana Photos: Albums Posts: 3,886	I have the K version. I agree with the reviews that the K is a sharp lens. I get great results (my opinion) at all stops. Colors are on the warmer side (my opinion) which I really like. I still use it every so often, but bought for indoor High School band performance pictures. Which worked well for me at f2.8. I don't think you would be disappointed with the K, even if you don't need it. A few examples At f2.8 At f4 At f8

06-24-2020, 08:34 AM - 2 Likes	#3
Wasp Pentaxian Join Date: Mar 2017 Location: Pretoria Photos: Gallery Posts: 4,661	This is a tough call. Both are pretty good and the difference is likely to be subtle. The "big" difference lies in the recipe for SMC which changed, meaning that colors are a little different. The K is slightly warmer AFAIK. My answer would depend on what you already have. I am taking the completionist stance on this. If you already have a bunch of M lenses, get another M. And vice versa. This one was made with my K 135mm f/3.5. It was my only K lens when I got it. The rest of my collection are mostly M series. That bothered my inner completionist no end until I got hold of a K 50mm f/1.2, but I feel slightly better now. I do feel the need for the K 85mm f/1.8 and one of the K 35mm lenses (not picky about aperture). Maybe a 24mm too. See where this goes? Last edited by Wasp; 06-24-2020 at 08:43 AM.

06-24-2020, 03:43 PM	#8
Riggomatic Loyal Site Supporter Join Date: Nov 2014 Location: Auburn, Indiana Photos: Albums Posts: 3,886	Originally posted by Wasp This is a tough call. Both are pretty good and the difference is likely to be subtle. The "big" difference lies in the recipe for SMC which changed, meaning that colors are a little different. The K is slightly warmer AFAIK. My answer would depend on what you already have. I am taking the completionist stance on this. If you already have a bunch of M lenses, get another M. And vice versa. This one was made with my K 135mm f/3.5. It was my only K lens when I got it. The rest of my collection are mostly M series. That bothered my inner completionist no end until I got hold of a K 50mm f/1.2, but I feel slightly better now. I do feel the need for the K 85mm f/1.8 and one of the K 35mm lenses (not picky about aperture). Maybe a 24mm too. See where this goes? I started with the K 135mm f3.5 as well... I've added: 24mm f2.8-- 30mm f2.8-- 35mm f3.5-- 50mm f1.4-- 85mm f1.8-- 105mm f2.8-- 120mm f2.8-- 135mm f2.5-- 200mm f4-- 300mm f4. A 35mm f2 will be arriving in a couple days to add to my collection. (Still waiting on a 50mm f1.2 deal and 200mm f2.5) Sticking with the same series K or M will also reduce your filter collection as well ( If a polarizer or ND is used).

06-24-2020, 03:58 PM - 1 Like	#9
MXLX Loyal Site Supporter Join Date: Apr 2019 Location: Western NC Photos: Albums Posts: 834 Original Poster	I have the 300/4 from the film days. On the lookout for a 24/2.8. 200/2.5? Dadgummit. -- Okay, looked up the cost of that one...I'm good. Back to the 120... Last edited by MXLX; 06-24-2020 at 04:15 PM.

06-24-2020, 09:15 AM - 2 Likes	#4
glasbak Veteran Member Join Date: Apr 2009 Location: Netherlands Posts: 369	Although I did not test these against each other, I expect the behavior to be like most K versus M lenses : K better image over the whole 24x36 frame, the M good in the centre, less in the edges/corners.

06-24-2020, 10:54 AM - 1 Like	#5
MXLX Loyal Site Supporter Join Date: Apr 2019 Location: Western NC Photos: Albums Posts: 834 Original Poster	I understand "completionist." I'm happy that I'm not at home to see where the gaps in the K collection are... Knowing the availables led to a buncha Takumars...

06-24-2020, 11:47 AM	#6
iheiramo Unoriginal Poster Join Date: Nov 2016 Location: Espoo Photos: Albums Posts: 3,182	I have no experience with K lenses, so can't do comparison between models. I have the M120 and I think the reviews don't do it justice. I have almost all M primes and I found 120 to be the best tele in series, if we consider M*300 as supertele and M85 as portrait lens. I just shot a month with it in Single In Challenge: SIC 2020 05 Pentax M120/2.8 FF \| Flickr

06-24-2020, 02:24 PM	#7
MXLX Loyal Site Supporter Join Date: Apr 2019 Location: Western NC Photos: Albums Posts: 834 Original Poster	^^^^^ Yeah, it's probably your fine work in the SIC that started the problem/search for me in the first place.

06-24-2020, 11:05 PM	#10
iheiramo Unoriginal Poster Join Date: Nov 2016 Location: Espoo Photos: Albums Posts: 3,182	Originally posted by MXLX ^^^^^ Yeah, it's probably your fine work in the SIC that started the problem/search for me in the first place. Sorry, didn't mean to Since you have mostly K series I might stick with that.

06-25-2020, 04:47 AM	#11
Wasp Pentaxian Join Date: Mar 2017 Location: Pretoria Photos: Gallery Posts: 4,661	I forgot that I have a K 200mm f/2.5. The looks of it is more like the M series than the K. The lettering around the barrel, I mean.

06-25-2020, 07:00 AM	#12
Jonathan Mac Pentaxian Join Date: Apr 2009 Location: Madrid, Spain Posts: 10,897	I would doubt there's a huge difference between them optically. The M is very nice and not that common, I've never seen a K for sale so they must be very rare indeed. I suppose in the K series it had to compete with the 135/2.5 which is superb (better than the M 120) so fewer were produced. I bought mine to replace the M 135/3.5 as a compact telephoto lens for travel (even on digital) as the more modern, slow zooms weren't cutting it in the image quality department. The M 135mm was better in that regard but the 120mm is better still, plus faster and a little shorter, which is better in most situations (180mm equivalent instead of 200mm equivalent). Last edited by Jonathan Mac; 06-25-2020 at 07:25 AM.

06-25-2020, 07:19 AM	#13
MXLX Loyal Site Supporter Join Date: Apr 2019 Location: Western NC Photos: Albums Posts: 834 Original Poster	@Riggomatic--I had looked at your pics several times before I saw the "baseball" in the last one.

06-25-2020, 05:24 PM - 1 Like	#14
MXLX Loyal Site Supporter Join Date: Apr 2019 Location: Western NC Photos: Albums Posts: 834 Original Poster	Thanks for the info, all. I happened upon a K 120 for a price well below the average in the reviews. On its way.

06-25-2020, 05:50 PM - 1 Like	#15
TwoUptons Loyal Site Supporter Join Date: Nov 2015 Photos: Albums Posts: 4,214	Good choice. I have the Takumar, and it's my favorite M42 tele... -Eric

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