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SMC Pentax-M 50mm F2 Review RSS Feed

SMC Pentax-M 50mm F2

Reviews Views Date of last review
98 304,447 Mon October 12, 2020
Recommended By Average Price Average User Rating
93% of reviewers $23.66 8.29
SMC Pentax-M 50mm F2

SMC Pentax-M 50mm F2
SMC Pentax-M 50mm F2
SMC Pentax-M 50mm F2

The smallest and slowest of the 50mm standard M lenses. This lens was manufactured over several years. The original version had a metal lens barrel like all other original M lenses. The late version had a plastic lens barrel and was manufactured from parts used in the A version. The aperture on the late version thus closes down linearly with the movement of the stop down lever like on all A lenses.

SMC Pentax-M 50mm F2
©, sharable with attribution
Image Format
Full-frame / 35mm film
Lens Mount
Pentax K
Aperture Ring
Yes (no A setting)
Automatic, 6 blades
5 elements, 5 groups
Mount Variant
Check camera compatibility
Max. Aperture
Min. Aperture
Min. Focus
45 cm
Max. Magnification
Filter Size
49 mm
Internal Focus
Field of View (Diag. / Horiz.)

APS-C: 32 ° / 27 °
Full frame: 47 ° / 40 °
Various types
Dedicated hard case
Lens Cap
Plastic clip-on
Weather Sealing
Other Features
Diam x Length
63 x 31 mm
160 g
Production Years
1979 to 1985
Engraved Name
smc PENTAX-M 1:2 50mm
Product Code
User reviews
Lens was sold without hood. Several hoods will fit like PH-S49 (50mm) and screw-in type metal and folding rubber hoods
Initially produced with a metal lens barrel and a weight of 165g, later with parts from the A counterpart and a plastic barrel, weighing in at 138g.
Manual FocusAperture RingFull-Frame SupportDiscontinued
Price History:

Add Review of SMC Pentax-M 50mm F2
Sort Reviews by: Date | Author | Rating | Recommendation | Likes (Descending) Showing Reviews 1-15 of 98
New Member

Registered: July, 2020
Posts: 10
Lens Review Date: October 12, 2020 I can recommend this lens: Yes | Price: $12.00 | Rating: 10 

Pros: Insanely cheap. Nicely built. Beautiful IQ
Cons: need to use stop down metering
Sharpness: 8    Aberrations: 7    Bokeh: 10    Handling: 10    Value: 10    Camera Used: Pentax Kr   

Things look just great with this lens.

My 50mm A 1.7 is sharper but somehow I prefer the rendering of this one.
Mechanics ( I have the earlier metal version) are also superior to the A , focussing in particular seems much smoother and my perception is that I am therefore more accurate with this on the camera. Despite the lack of electronic contacts this lens somehow handles better (at least when I remember to use the green button)

Coatings are pretty good but I see veiling flare more often than if I use a modern lens.

This is really lovely as a portrait lens on my Kr, I commonly use it at 2.8. For the cost I don't think it can be beaten.
Loyal Site Supporter

Registered: September, 2017
Location: Medellín
Posts: 1,286
Lens Review Date: December 23, 2019 I can recommend this lens: Yes | Price: $20.00 | Rating: 10 

Pros: Small, compact, light, pancake-like, 49mm filter ring.

For the price and size, you can't go wrong. Should make part of your M (miniature) lens set. It's all you need as a photography/art student.
New Member

Registered: October, 2019
Posts: 2
Lens Review Date: November 4, 2019 I can recommend this lens: Yes | Price: $30.00 | Rating: 10 

Pros: Excellent low light results
Cons: none
Sharpness: 9    Aberrations: 9    Bokeh: 9    Handling: 10    Value: 10    Camera Used: K-50   

Another great lens with good sharpness, provided you are adept at dialing in focus manually.

- Pentax-M 50mm F2
- Pentax K-50 DSLR (16.3mp)
- mounted on tripod
- aperture priority
- ISO 100
- white balance set to AWB
- focus peaking enabled on camera
- using manual focus assist
- 2-second timer

Right-click the following image and click "Open Image in New Tab", then zoom in.

All jpegs right from the my Pentax K-50.

F4.5, 2 second exposure:

Here are 3 shots from my send copy of this lens:

F5.6, 2-3 second exposure:

New Member

Registered: November, 2016
Posts: 7
Lens Review Date: October 24, 2019 I can recommend this lens: Yes | Price: $25.00 | Rating: 7 

Pros: very affordable for F2 prime lens
Cons: Not as sharp as other lenses of the same specs
Sharpness: 6    Aberrations: 6    Bokeh: 7    Handling: 8    Value: 7   

This is a hard lens to review. It's a very affordable lens from one of the most prestigious camera makers. While it doesn't have the build quality of the older Super-Takumars, its not built badly. It features Pentax's very good multicoating which resists flare, but its image quality is not as good as some competitors. My Ricoh XR Rikenon is sharper wide open, and so is the its brother, the Auto Sears lens. While those lenses lack multicoating, they can be bought cheaper than the Pentax-M. Color rendition is good with the Pentax-M and the bokeh is just okay. When compared to very good modern day zoom lenses, the Pentax is a no brainer for price/performance ratio. Would I recommend it? Only if you can get it for less than $25. I believe its a good starter lens for people who want to use vintage manual lenses.

I have had both the old and newer versions of the lens. Try to get the older version. It is build better with slightly less plastic and QC might actually be better as my later version actually had a defect in one of the lens elements. A small chunk of glass was missing and was clearly there before they polished the lens and added SMC. While it didn't effect image quality, it is still not what I expect from Pentax.
New Member

Registered: February, 2019
Posts: 12
Lens Review Date: October 8, 2019 I can recommend this lens: Yes | Price: N/A | Rating: 10 

Pros: Small and easy to use
Cons: None
Sharpness: 9    Aberrations: 8    Bokeh: 7    Handling: 10    Value: 10    Camera Used: Pentax film and KX   

There are some very odd reviews here that seem to rate this lens so far down that it makes me wonder what is going on! This lens is actually as good as the Pentax M SMC 1.7 version; the only difference being that it has a slightly smaller lens diameter. All this means is that at f2 it's not so sharp and it can't function as well in very dark contexts, but how many people genuinely go that low down the aperture scale when taking photos? At f5.6 both versions are identical and right up to the smaller aperture range. Being more affordable, I think that makes this lens as good as the f1.7 version.

And maybe those people who have really attacked this lens need to check to see if their copy is full of dirt, dust and fungus because the lens is decades old. This is not the fault of the lens! Just get your old lens cleaned up and then re-write your reviews, people!

The f2 is a lovely, easy to use, small, well-built and gorgeously coated lens that is a joy to rely upon and use to take wonderful photos in a vast range of lighting conditions and contexts. It just works, and works very well indeed.
Senior Member

Registered: November, 2018
Posts: 135
Lens Review Date: October 3, 2019 I can recommend this lens: Yes | Price: N/A | Rating: N/A 


Site Supporter

Registered: June, 2013
Location: Utrecht
Posts: 61
Lens Review Date: August 11, 2019 I can recommend this lens: Yes | Price: $10.00 | Rating: 9 

Pros: Cheap, build quality, decent performer stopped down
Cons: M1.7 is better and also costs almost nothing...
Sharpness: 8    Aberrations: 8    Bokeh: 9    Handling: 10    Value: 10    Camera Used: ME super to K1ii   

Wide open this lens is less good compared with the M1.7 at F2.0, visible less sharp, visible more ghosting. Stopped down this lens is realy good. But... For a few more €$ you can get a M1.7 which is clearly a better performer. Build quality and handling of the M2.0 are great like all M-lenses. I own the metal "made in Japan" version.

See also

Picture wide open:

Forum Member

Registered: February, 2016
Location: Moab, Utah
Posts: 90

5 users found this helpful
Lens Review Date: July 29, 2017 I can recommend this lens: Yes | Price: $31.00 | Rating: N/A 

Pros: Fine contrast, Color Punch, Sharpness in that order
Cons: bokeh, fringing possible at f2 until 2.8, doesn't look cool
Sharpness: 10    Aberrations: 9    Bokeh: 8    Handling: 10    Value: 10   

This is the best Pentax 50mm for landscapes. I tested the SMC 50 1.2 & 1.4 with 52mm filter rings and 8 bladed apertures, SMC Tak 55 1.8, and Super Tak 50 1.4... Hands down, this one offers the best fine contrast and color punch. The 55 1.8 is close, but isn't sharp from f13 to f16 and doesn't even have 22... This one also gives the best flare resistance out of them all, though can fringe when used wide open at f2. fringing clears up completely by about 2.8. Hence, this is "The" 50mm landscape lens from Pentax. I use this one a lot more than my SMC 1.2, which is reserved for bokeh and dreaminess. This 5 element design is barely more than a Tessar and performs similarly with a lot of 3d pop. Bokeh is not great - this is not the design of the lens, and why I also recommend the SMC 50 1.2 or Takumar 55 1.8 in addition to this 50.

For anyone interested, I compared 5 different 50mm lens options from Pentax and posted it on YouTube:

On my copy, the rubber focusing ring was slipping so a thin bead of high temperature black RTV gasket maker applied with a toothpick underneath fixed that. The focusing helicoid is so small on this lens that it feels like it's not even moving. Glassy focus and clicky aperture, typical of M series Pentax.

More people should get over fast lenses and start using readily available gems like this one.
New Member

Registered: June, 2017
Posts: 1
Lens Review Date: June 3, 2017 I can recommend this lens: Yes | Price: $25.00 | Rating: 10 

Pros: great DOF, Build quality, Long focus throw, Sharpness
Cons: Can't think of anything at this moment
Sharpness: 8    Aberrations: 8    Bokeh: 8    Handling: 10    Value: 10    Camera Used: Panasonic Lumix GX80   

I have been looking at this forum for some time now. When i realised i could use the old pentax lenses my father used 30/35 years ago, i tried to use them with a focal reducer from Pixco on my Panasonic Lumix GX80/GX85 and with great results. I will show some samples with this post.

This lens is great. The focus throw is buttery smooth and the sharpness is very good with the camera i am using. When i use this 50mm lens with a m4/3 camera and the focal reducer it comes down to 76mm, but the results are great. The sharpness at F2.0 is reasonable and at f8 it is ultra sharp. The mood and depth of field of this lens is beautifull. It feels like quality and it is.
Inactive Account

Registered: May, 2016
Posts: 1
Lens Review Date: April 29, 2017 I can recommend this lens: Yes | Price: $5.00 | Rating: 9 

Pros: sharp @ 2.8, metal body, cheap, bokeh
Cons: soft wide open
Sharpness: 8    Aberrations: 8    Bokeh: 9    Handling: 9    Value: 9    Camera Used: Pentax K500   

very dreamy wide open with a little of purple fringing (the M 1.4 @ 2 has no this dreamy effects), perfect solution for anyone that want to use the legendary M series of Pentax (but for 10 bucks more you can buy the M 1.7 that is really the state of the art of 1.7 50mm). The bokeh is very good (round wide open and hexagonal stopped down - not ninja star like the 1.7). At 2.8 is very sharp with a very nice color rendition.

I recommend this lens but only if you need an extra 50mm and if the price is less than 15 bucks.
New Member

Registered: October, 2014
Posts: 9

1 user found this helpful
Lens Review Date: February 16, 2017 I can recommend this lens: Yes | Price: $60.00 | Rating: 9 

Pros: Small, good build q, pleasure to use.
Cons: Soft-ish wide open.
Sharpness: 8    Bokeh: 10    Handling: 10    Value: 9    Camera Used: K-5   

This is a good lens an I enjoy using it.
Build quality of this lens is very good and it also looks nice.
It is small and comfortable to use, and has smooth focus ring.
Bokeh is excellent, though the lens lacks sharpness when wide open (also it's a manual lens, so a lot of depends on photographer). It is sharp when stopped down.

Would I recommend it? Well, That depends on at what price you can get it.
For what I paid for it, I could've gotten the f1.7 version instead (Don't know if it's any better though, as I've never tried it, but 1.7 looks better than 2.0 on paper ).
For 20-40USD - it's a no brainer.

Senior Member

Registered: December, 2015
Location: Brisbane, Australia
Posts: 134
Lens Review Date: January 19, 2017 I can recommend this lens: No | Price: $10.00 | Rating: 4 

Pros: Cheap, easy to find, aberrations well controlled
Cons: Soft, way out-classed by the other 50mm options
Sharpness: 3    Aberrations: 8    Bokeh: 6    Handling: 5    Value: 8    Camera Used: K3-II   

My copy of this lens came attached to a set of K-mount bellows I bought. So I can't really deny the amazing value offered by it (you can get it for change!). Originally these were the cheap-as kit lens option (vs the not as cheap 50mm f1.7 and f1.4 options). Definitely not the worst option at the time, but now, with so many better legacy lenses going for cheap, I cannot recommend hunting one down - chances are you will get one attached to an old body or something else anyway.

Image quality wise, the lens is soft wide open, unable at f4, acceptably sharp at f5.6, and even good at f8. Problem is that this leaves in heavily out-classed by its faster brothers - both of which (even the notoriously soft f1.4) are sharper, earlier.

Aberrations are surprisingly will controlled. Distortion is non-existent (as you would expect from a 50mm lens), but even chromatic aberration is minimal. Apart from cost, this is its biggest plus.

Bokeh is nice and smooth, but no better than from its faster brothers.

My example's aperture ring is quite resistant to moving (not great on a lens which doesn't allow body-aperture-control!). This is probably down to age and lubricants drying out, but compared to other Pentax lenses I have with metal aperture rings, it is disappointing. Otherwise handling is as you would expect from a M-era manual lens.

Despite the lens' cheapness, I really cannot recommend the lens. Optically it is just 'meh', and with so many other cheap manual 50mm lenses out there, you can easily pick up something much better (I recommend any of the f1.7 versions). If you really want a 50mm f2, I'd suggest tracking down the A-series version, if only because it has the aperture contacts, meaning you are not restricted to green-button metering on DSLRs.
New Member

Registered: February, 2009
Location: Seattle
Posts: 19

1 user found this helpful
Lens Review Date: October 24, 2016 I can recommend this lens: Yes | Price: $25.00 | Rating: 9 

Pros: very good sharpness, bokeh, color, size, price, well built
Cons: none (with this price)
Sharpness: 9    Aberrations: 9    Bokeh: 9    Handling: 10    Value: 10    Camera Used: K5II   

Don't know why this lens has a low score
I also have the A50 F1.4 but personally, I think the M50 f2.0 easier to handle

New Member

Registered: September, 2016
Posts: 3
Lens Review Date: September 13, 2016 I can recommend this lens: No | Price: $20.00 | Rating: 8 

Pros: Inexpensive, almost to the point of being free
Cons: Soft at f2.0
Sharpness: 6    Aberrations: 9    Bokeh: 8    Handling: 8    Value: 10    Camera Used: K-30   

I also own the smc pentax 55mm f2.0 so I could make a comparison, and this lens does worse all across the board. It is very soft at f2.0 making it a 50mm/f2.8 in practical use. At the same time it's hard to complain over a lens that costs peanuts. It's well built and handles nice. But just add a $20-30 and there are excellent options on the used market performing way better. Grade is of course in relationship to price, probably the least expensive pentax lens out there.
New Member

Registered: February, 2013
Posts: 21

1 user found this helpful
Lens Review Date: June 23, 2016 I can recommend this lens: Yes | Price: N/A | Rating: 9 

Sharpness: 8    Aberrations: 8    Bokeh: 9    Handling: 8    Value: 10    Camera Used: K3, K7d, K01   

Like most others, I got this cheap, as part of a collection of old lenses and other things.

I really like the Pentax m42 primes and probably wouldn't have bought this lens if it hadn't come along with other things I wanted. And that would have been a huge mistake. This is what I like about it:

The Bokeh really appeals to me. I am very fond of this lens.
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